Re: [RE-wrenches] Passive Battery Venting
One big advantage of not venting AGM batteries to the outside is that when something goes wrong you will know it. A well vented system could have one bad battery ruin the entire pack before the problem was detected. At 08:12 AM 10/30/2014, you wrote: To do it totally passive you will need a long (tall) pipe up the side of the building, probably painted a dark color to have the sun help warm the tube to help encourage it to vent up, not draw into the building. Put a 180 on the top to keep the rain out and a screen to keep out the bugs. With outside venting the batteries will just draw in room temperature air, if the room is 70 the battery min temp will be 70. If they are in a basement they will naturally draw in outside air, run the vent as high as you can to help prevent that. If you are using a Classic use the relay to turn the fan on and off at a specific battery voltage. Use a brushless fan and a voltage powered relay if no other choice. Do not put the relay in the battery box! Sealed batteries do need to be vented. I have seen them gas when things go wrong, not pleasant. I wouldn't do it without a fan for LA batteries but it would work for sealed. If the home has a makeup air system or huge exhaust system all bets are off. Just some thoughts, Bob Ellison -Original Message- From: RE-wrenches [mailto:re-wrenches-boun...@lists.re-wrenches.org] On Behalf Of Drake Sent: Wednesday, October 29, 2014 8:19 PM To: RE-wrenches Subject: Re: [RE-wrenches] Passive Battery Venting Hi Daniel, I typically vent them the way you do, which will allow any small amount of hydrogen out. The customer is absolutely adamant about venting these to the outside. I will cooperate so long as his method doesn't compromise the system through cooling the batteries unnecessarily in the dead of winter. He is a lawyer and came to the conclusion of the need for venting to the outside from reading the NEC which says that sealed batteries require the same amount of ventilation as liquid lead acid batteries. The code also says to vent appropriate to battery technology, so the code says two conflicting things. On the other hand, it doesn't say that liquid electrolyte batteries need to be vented to the outside. They will sure stink if you vent them to the inside. Drake At 09:54 AM 10/29/2014, you wrote: I just re-read the original post Drake. These are AGM batteries. Do you have a belt, suspenders,...then a rocket pack type of client here? We typically vent our AGM boxes with small louver vents top and bottom to allow the batteries to ventilate for cooling purposes, not H2 concerns. With Regards, Daniel Young, NABCEP Certified PV Installation ProfessionalTM: Cert #031508-90 NABCEP Certified Solar Heating InstallerTM: Cert #SH031409-13 -Original Message- From: RE-wrenches [mailto:re-wrenches-boun...@lists.re-wrenches.org] On Behalf Of Ray Walters Sent: Tuesday, October 28, 2014 11:12 PM To: RE-wrenches Subject: Re: [RE-wrenches] Passive Battery Venting That's why we usually have the batteries in a garage, basement, or out building that is not open to the living space. I've seen some cases of very well sealed and insulated enclosures allowing batteries to over heat, and also build up a lot of acid damaged connections. Boxes I've seen with more air space and less sealing don't get this build up, but you're correct: they do occasionally allow H2S into the surrounding area. R.Ray Walters CTO, Solarray, Inc Nabcep Certified PV Installer, Licensed Master Electrician Solar Design Engineer 303 505-8760 On 10/28/2014 8:10 PM, Jerry Shafer wrote: We do what we can to seal the enclosure so if or when a battery fails and really gasses off the two vents on the same wall regardless of wind direction will vent the gas. If it is not sealed then the gas can travel through out the area this is not advised. ___ List sponsored by Redwood Alliance List Address: RE-wrenches@lists.re-wrenches.org Change listserver email address settings: http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org List-Archive: http://www.mail-archive.com/re-wrenches@lists.re-wrenches.org/maillist.html List rules etiquette: www.re-wrenches.org/etiquette.htm Check out or update participant bios: www.members.re-wrenches.org - No virus found in this message. Checked by AVG - www.avg.com Version: 2012.0.2247 / Virus Database: 4031/7973 - Release Date: 10/29/14 - No virus found in this message. Checked by AVG - www.avg.com Version: 2012.0.2247 / Virus Database: 4031/7973 - Release Date: 10/29/14 ___ List sponsored by Redwood Alliance List Address: RE-wrenches@lists.re-wrenches.org Change listserver email address settings: http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org List-Archive: http://www.mail-archive.com/re-wrenches@lists.re-wrenches.org/maillist.html List rules etiquette: www.re
Re: [RE-wrenches] Passive Battery Venting
Drake, Please explain what might happen if something went wrong with one battery, and the Phil Forest South Mountain Company On Oct 31, 2014, at 8:42 AM, Drake drake.chamber...@redwoodalliance.org wrote: One big advantage of not venting AGM batteries to the outside is that when something goes wrong you will know it. A well vented system could have one bad battery ruin the entire pack before the problem was detected. At 08:12 AM 10/30/2014, you wrote: To do it totally passive you will need a long (tall) pipe up the side of the building, probably painted a dark color to have the sun help warm the tube to help encourage it to vent up, not draw into the building. Put a 180 on the top to keep the rain out and a screen to keep out the bugs. With outside venting the batteries will just draw in room temperature air, if the room is 70 the battery min temp will be 70. If they are in a basement they will naturally draw in outside air, run the vent as high as you can to help prevent that. If you are using a Classic use the relay to turn the fan on and off at a specific battery voltage. Use a brushless fan and a voltage powered relay if no other choice. Do not put the relay in the battery box! Sealed batteries do need to be vented. I have seen them gas when things go wrong, not pleasant. I wouldn't do it without a fan for LA batteries but it would work for sealed. If the home has a makeup air system or huge exhaust system all bets are off. Just some thoughts, Bob Ellison -Original Message- From: RE-wrenches [mailto:re-wrenches-boun...@lists.re-wrenches.org] On Behalf Of Drake Sent: Wednesday, October 29, 2014 8:19 PM To: RE-wrenches Subject: Re: [RE-wrenches] Passive Battery Venting Hi Daniel, I typically vent them the way you do, which will allow any small amount of hydrogen out. The customer is absolutely adamant about venting these to the outside. I will cooperate so long as his method doesn't compromise the system through cooling the batteries unnecessarily in the dead of winter. He is a lawyer and came to the conclusion of the need for venting to the outside from reading the NEC which says that sealed batteries require the same amount of ventilation as liquid lead acid batteries. The code also says to vent appropriate to battery technology, so the code says two conflicting things. On the other hand, it doesn't say that liquid electrolyte batteries need to be vented to the outside. They will sure stink if you vent them to the inside. Drake At 09:54 AM 10/29/2014, you wrote: I just re-read the original post Drake. These are AGM batteries. Do you have a belt, suspenders,...then a rocket pack type of client here? We typically vent our AGM boxes with small louver vents top and bottom to allow the batteries to ventilate for cooling purposes, not H2 concerns. With Regards, Daniel Young, NABCEP Certified PV Installation ProfessionalTM: Cert #031508-90 NABCEP Certified Solar Heating InstallerTM: Cert #SH031409-13 -Original Message- From: RE-wrenches [mailto:re-wrenches-boun...@lists.re-wrenches.org] On Behalf Of Ray Walters Sent: Tuesday, October 28, 2014 11:12 PM To: RE-wrenches Subject: Re: [RE-wrenches] Passive Battery Venting That's why we usually have the batteries in a garage, basement, or out building that is not open to the living space. I've seen some cases of very well sealed and insulated enclosures allowing batteries to over heat, and also build up a lot of acid damaged connections. Boxes I've seen with more air space and less sealing don't get this build up, but you're correct: they do occasionally allow H2S into the surrounding area. R.Ray Walters CTO, Solarray, Inc Nabcep Certified PV Installer, Licensed Master Electrician Solar Design Engineer 303 505-8760 On 10/28/2014 8:10 PM, Jerry Shafer wrote: We do what we can to seal the enclosure so if or when a battery fails and really gasses off the two vents on the same wall regardless of wind direction will vent the gas. If it is not sealed then the gas can travel through out the area this is not advised. ___ List sponsored by Redwood Alliance List Address: RE-wrenches@lists.re-wrenches.org Change listserver email address settings: http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org List-Archive: http://www.mail-archive.com/re-wrenches@lists.re-wrenches.org/maillist.html List rules etiquette: www.re-wrenches.org/etiquette.htm Check out or update participant bios: www.members.re-wrenches.org - No virus found in this message. Checked by AVG - www.avg.com Version: 2012.0.2247 / Virus Database: 4031/7973 - Release Date: 10/29/14 - No virus found in this message. Checked by AVG - www.avg.com Version: 2012.0.2247 / Virus Database: 4031/7973 - Release Date: 10/29/14
Re: [RE-wrenches] Passive Battery Venting
Drake, Please explain what might happen if something went wrong with one battery, when they are not vented to outside. How would we know it? Thank you. Phil Forest South Mountain Company On Oct 31, 2014, at 8:42 AM, Drake drake.chamber...@redwoodalliance.org wrote: One big advantage of not venting AGM batteries to the outside is that when something goes wrong you will know it. A well vented system could have one bad battery ruin the entire pack before the problem was detected. At 08:12 AM 10/30/2014, you wrote: To do it totally passive you will need a long (tall) pipe up the side of the building, probably painted a dark color to have the sun help warm the tube to help encourage it to vent up, not draw into the building. Put a 180 on the top to keep the rain out and a screen to keep out the bugs. With outside venting the batteries will just draw in room temperature air, if the room is 70 the battery min temp will be 70. If they are in a basement they will naturally draw in outside air, run the vent as high as you can to help prevent that. If you are using a Classic use the relay to turn the fan on and off at a specific battery voltage. Use a brushless fan and a voltage powered relay if no other choice. Do not put the relay in the battery box! Sealed batteries do need to be vented. I have seen them gas when things go wrong, not pleasant. I wouldn't do it without a fan for LA batteries but it would work for sealed. If the home has a makeup air system or huge exhaust system all bets are off. Just some thoughts, Bob Ellison -Original Message- From: RE-wrenches [mailto:re-wrenches-boun...@lists.re-wrenches.org] On Behalf Of Drake Sent: Wednesday, October 29, 2014 8:19 PM To: RE-wrenches Subject: Re: [RE-wrenches] Passive Battery Venting Hi Daniel, I typically vent them the way you do, which will allow any small amount of hydrogen out. The customer is absolutely adamant about venting these to the outside. I will cooperate so long as his method doesn't compromise the system through cooling the batteries unnecessarily in the dead of winter. He is a lawyer and came to the conclusion of the need for venting to the outside from reading the NEC which says that sealed batteries require the same amount of ventilation as liquid lead acid batteries. The code also says to vent appropriate to battery technology, so the code says two conflicting things. On the other hand, it doesn't say that liquid electrolyte batteries need to be vented to the outside. They will sure stink if you vent them to the inside. Drake At 09:54 AM 10/29/2014, you wrote: I just re-read the original post Drake. These are AGM batteries. Do you have a belt, suspenders,...then a rocket pack type of client here? We typically vent our AGM boxes with small louver vents top and bottom to allow the batteries to ventilate for cooling purposes, not H2 concerns. With Regards, Daniel Young, NABCEP Certified PV Installation ProfessionalTM: Cert #031508-90 NABCEP Certified Solar Heating InstallerTM: Cert #SH031409-13 -Original Message- From: RE-wrenches [mailto:re-wrenches-boun...@lists.re-wrenches.org] On Behalf Of Ray Walters Sent: Tuesday, October 28, 2014 11:12 PM To: RE-wrenches Subject: Re: [RE-wrenches] Passive Battery Venting That's why we usually have the batteries in a garage, basement, or out building that is not open to the living space. I've seen some cases of very well sealed and insulated enclosures allowing batteries to over heat, and also build up a lot of acid damaged connections. Boxes I've seen with more air space and less sealing don't get this build up, but you're correct: they do occasionally allow H2S into the surrounding area. R.Ray Walters CTO, Solarray, Inc Nabcep Certified PV Installer, Licensed Master Electrician Solar Design Engineer 303 505-8760 On 10/28/2014 8:10 PM, Jerry Shafer wrote: We do what we can to seal the enclosure so if or when a battery fails and really gasses off the two vents on the same wall regardless of wind direction will vent the gas. If it is not sealed then the gas can travel through out the area this is not advised. ___ List sponsored by Redwood Alliance List Address: RE-wrenches@lists.re-wrenches.org Change listserver email address settings: http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org List-Archive: http://www.mail-archive.com/re-wrenches@lists.re-wrenches.org/maillist.html List rules etiquette: www.re-wrenches.org/etiquette.htm Check out or update participant bios: www.members.re-wrenches.org - No virus found in this message. Checked by AVG - www.avg.com Version: 2012.0.2247 / Virus Database: 4031/7973 - Release Date: 10/29/14 - No virus found in this message. Checked by AVG - www.avg.com Version: 2012.0.2247 / Virus Database: 4031/7973
Re: [RE-wrenches] Passive Battery Venting
You would smell it. Miller Solar On Oct 31, 2014, at 1:20 PM, Phil Forest pfor...@southmountain.com wrote: Drake, Please explain what might happen if something went wrong with one battery, when they are not vented to outside. How would we know it? Thank you. Phil Forest South Mountain Company On Oct 31, 2014, at 8:42 AM, Drake drake.chamber...@redwoodalliance.org wrote: One big advantage of not venting AGM batteries to the outside is that when something goes wrong you will know it. A well vented system could have one bad battery ruin the entire pack before the problem was detected. At 08:12 AM 10/30/2014, you wrote: To do it totally passive you will need a long (tall) pipe up the side of the building, probably painted a dark color to have the sun help warm the tube to help encourage it to vent up, not draw into the building. Put a 180 on the top to keep the rain out and a screen to keep out the bugs. With outside venting the batteries will just draw in room temperature air, if the room is 70 the battery min temp will be 70. If they are in a basement they will naturally draw in outside air, run the vent as high as you can to help prevent that. If you are using a Classic use the relay to turn the fan on and off at a specific battery voltage. Use a brushless fan and a voltage powered relay if no other choice. Do not put the relay in the battery box! Sealed batteries do need to be vented. I have seen them gas when things go wrong, not pleasant. I wouldn't do it without a fan for LA batteries but it would work for sealed. If the home has a makeup air system or huge exhaust system all bets are off. Just some thoughts, Bob Ellison -Original Message- From: RE-wrenches [mailto:re-wrenches-boun...@lists.re-wrenches.org] On Behalf Of Drake Sent: Wednesday, October 29, 2014 8:19 PM To: RE-wrenches Subject: Re: [RE-wrenches] Passive Battery Venting Hi Daniel, I typically vent them the way you do, which will allow any small amount of hydrogen out. The customer is absolutely adamant about venting these to the outside. I will cooperate so long as his method doesn't compromise the system through cooling the batteries unnecessarily in the dead of winter. He is a lawyer and came to the conclusion of the need for venting to the outside from reading the NEC which says that sealed batteries require the same amount of ventilation as liquid lead acid batteries. The code also says to vent appropriate to battery technology, so the code says two conflicting things. On the other hand, it doesn't say that liquid electrolyte batteries need to be vented to the outside. They will sure stink if you vent them to the inside. Drake At 09:54 AM 10/29/2014, you wrote: I just re-read the original post Drake. These are AGM batteries. Do you have a belt, suspenders,...then a rocket pack type of client here? We typically vent our AGM boxes with small louver vents top and bottom to allow the batteries to ventilate for cooling purposes, not H2 concerns. With Regards, Daniel Young, NABCEP Certified PV Installation ProfessionalTM: Cert #031508-90 NABCEP Certified Solar Heating InstallerTM: Cert #SH031409-13 -Original Message- From: RE-wrenches [mailto:re-wrenches-boun...@lists.re-wrenches.org] On Behalf Of Ray Walters Sent: Tuesday, October 28, 2014 11:12 PM To: RE-wrenches Subject: Re: [RE-wrenches] Passive Battery Venting That's why we usually have the batteries in a garage, basement, or out building that is not open to the living space. I've seen some cases of very well sealed and insulated enclosures allowing batteries to over heat, and also build up a lot of acid damaged connections. Boxes I've seen with more air space and less sealing don't get this build up, but you're correct: they do occasionally allow H2S into the surrounding area. R.Ray Walters CTO, Solarray, Inc Nabcep Certified PV Installer, Licensed Master Electrician Solar Design Engineer 303 505-8760 On 10/28/2014 8:10 PM, Jerry Shafer wrote: We do what we can to seal the enclosure so if or when a battery fails and really gasses off the two vents on the same wall regardless of wind direction will vent the gas. If it is not sealed then the gas can travel through out the area this is not advised. ___ List sponsored by Redwood Alliance List Address: RE-wrenches@lists.re-wrenches.org Change listserver email address settings: http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org List-Archive: http://www.mail-archive.com/re-wrenches@lists.re-wrenches.org/maillist.html List rules etiquette: www.re-wrenches.org/etiquette.htm Check out or update participant bios: www.members.re-wrenches.org - No virus found in this message. Checked by AVG - www.avg.com Version: 2012.0.2247 / Virus Database: 4031/7973 - Release Date: 10/29/14
Re: [RE-wrenches] Passive Battery Venting
Hey Wrenches. Looks like this came from Concorde, Allen S posted it in Feb of 2014... I don't know how up to date it is.. It's got some good information about the different gassing rates of VRLA batteries. Most all VRLA's are pretty close to these numbers. The specific numbers on Surrette AGM is When the battery is float charged at 2.3V/cell, the amount of the gas generated will be approx. 0.0187 cc/hr/AH/cell. When the battery is charged above 2.4V/cell, the amount of the gas generated will be approx. 0.0366 cc/hr/AH/cell. Since I've been a Surrette, most of the inspectors I've talked with don't worry about the normal operation of the battery bank, they worry about if something goes wrong with the batteries, or the chargers. They tend to like things to be designed so that their rear ends aren't in a sling if things go wrong. So to make them happy, it can be a good idea to design to when things fail, also adding a hydrogen detector sometimes will pacify them. The issue I hear most is without moving the air out when there is too much Hydrogen, is if you have a loose connection, or it's in the same room as the inverter/controller and there is a spark/ignition source things tend to go bang and most people don't like that. In most cases this will cause the top of the battery to blow off. Steve Higgins Technical Services Manager P: +1.902.597.4020 M: +1.206.790.5840 F: +1.902.597.8447 Surrette Battery Company Exclusive manufacturer of -Original Message- From: RE-wrenches [mailto:re-wrenches-boun...@lists.re-wrenches.org] On Behalf Of William Miller Sent: Friday, October 31, 2014 1:44 PM To: RE-wrenches Subject: Re: [RE-wrenches] Passive Battery Venting You would smell it. Miller Solar On Oct 31, 2014, at 1:20 PM, Phil Forest pfor...@southmountain.com wrote: Drake, Please explain what might happen if something went wrong with one battery, when they are not vented to outside. How would we know it? Thank you. Phil Forest South Mountain Company On Oct 31, 2014, at 8:42 AM, Drake drake.chamber...@redwoodalliance.org wrote: One big advantage of not venting AGM batteries to the outside is that when something goes wrong you will know it. A well vented system could have one bad battery ruin the entire pack before the problem was detected. At 08:12 AM 10/30/2014, you wrote: To do it totally passive you will need a long (tall) pipe up the side of the building, probably painted a dark color to have the sun help warm the tube to help encourage it to vent up, not draw into the building. Put a 180 on the top to keep the rain out and a screen to keep out the bugs. With outside venting the batteries will just draw in room temperature air, if the room is 70 the battery min temp will be 70. If they are in a basement they will naturally draw in outside air, run the vent as high as you can to help prevent that. If you are using a Classic use the relay to turn the fan on and off at a specific battery voltage. Use a brushless fan and a voltage powered relay if no other choice. Do not put the relay in the battery box! Sealed batteries do need to be vented. I have seen them gas when things go wrong, not pleasant. I wouldn't do it without a fan for LA batteries but it would work for sealed. If the home has a makeup air system or huge exhaust system all bets are off. Just some thoughts, Bob Ellison -Original Message- From: RE-wrenches [mailto:re-wrenches-boun...@lists.re-wrenches.org] On Behalf Of Drake Sent: Wednesday, October 29, 2014 8:19 PM To: RE-wrenches Subject: Re: [RE-wrenches] Passive Battery Venting Hi Daniel, I typically vent them the way you do, which will allow any small amount of hydrogen out. The customer is absolutely adamant about venting these to the outside. I will cooperate so long as his method doesn't compromise the system through cooling the batteries unnecessarily in the dead of winter. He is a lawyer and came to the conclusion of the need for venting to the outside from reading the NEC which says that sealed batteries require the same amount of ventilation as liquid lead acid batteries. The code also says to vent appropriate to battery technology, so the code says two conflicting things. On the other hand, it doesn't say that liquid electrolyte batteries need to be vented to the outside. They will sure stink if you vent them to the inside. Drake At 09:54 AM 10/29/2014, you wrote: I just re-read the original post Drake. These are AGM batteries. Do you have a belt, suspenders,...then a rocket pack type of client here? We typically vent our AGM boxes with small louver vents top and bottom to allow the batteries to ventilate for cooling purposes, not H2 concerns. With Regards, Daniel Young, NABCEP Certified PV Installation ProfessionalTM: Cert #031508-90 NABCEP Certified Solar Heating InstallerTM: Cert #SH031409-13 -Original Message- From: RE-wrenches [mailto:re
Re: [RE-wrenches] Passive Battery Venting
.a heck of a lot easier to water the darn thing. - Original Message - From: Steve Higgins st...@surrette.com To: RE-wrenches re-wrenches@lists.re-wrenches.org Sent: Friday, October 31, 2014 2:07 PM Subject: Re: [RE-wrenches] Passive Battery Venting Hey Wrenches. Looks like this came from Concorde, Allen S posted it in Feb of 2014... I don't know how up to date it is.. It's got some good information about the different gassing rates of VRLA batteries. Most all VRLA's are pretty close to these numbers. The specific numbers on Surrette AGM is When the battery is float charged at 2.3V/cell, the amount of the gas generated will be approx. 0.0187 cc/hr/AH/cell. When the battery is charged above 2.4V/cell, the amount of the gas generated will be approx. 0.0366 cc/hr/AH/cell. Since I've been a Surrette, most of the inspectors I've talked with don't worry about the normal operation of the battery bank, they worry about if something goes wrong with the batteries, or the chargers. They tend to like things to be designed so that their rear ends aren't in a sling if things go wrong. So to make them happy, it can be a good idea to design to when things fail, also adding a hydrogen detector sometimes will pacify them. The issue I hear most is without moving the air out when there is too much Hydrogen, is if you have a loose connection, or it's in the same room as the inverter/controller and there is a spark/ignition source things tend to go bang and most people don't like that. In most cases this will cause the top of the battery to blow off. Steve Higgins Technical Services Manager P: +1.902.597.4020 M: +1.206.790.5840 F: +1.902.597.8447 Surrette Battery Company Exclusive manufacturer of -Original Message- From: RE-wrenches [mailto:re-wrenches-boun...@lists.re-wrenches.org] On Behalf Of William Miller Sent: Friday, October 31, 2014 1:44 PM To: RE-wrenches Subject: Re: [RE-wrenches] Passive Battery Venting You would smell it. Miller Solar On Oct 31, 2014, at 1:20 PM, Phil Forest pfor...@southmountain.com wrote: Drake, Please explain what might happen if something went wrong with one battery, when they are not vented to outside. How would we know it? Thank you. Phil Forest South Mountain Company On Oct 31, 2014, at 8:42 AM, Drake drake.chamber...@redwoodalliance.org wrote: One big advantage of not venting AGM batteries to the outside is that when something goes wrong you will know it. A well vented system could have one bad battery ruin the entire pack before the problem was detected. At 08:12 AM 10/30/2014, you wrote: To do it totally passive you will need a long (tall) pipe up the side of the building, probably painted a dark color to have the sun help warm the tube to help encourage it to vent up, not draw into the building. Put a 180 on the top to keep the rain out and a screen to keep out the bugs. With outside venting the batteries will just draw in room temperature air, if the room is 70 the battery min temp will be 70. If they are in a basement they will naturally draw in outside air, run the vent as high as you can to help prevent that. If you are using a Classic use the relay to turn the fan on and off at a specific battery voltage. Use a brushless fan and a voltage powered relay if no other choice. Do not put the relay in the battery box! Sealed batteries do need to be vented. I have seen them gas when things go wrong, not pleasant. I wouldn't do it without a fan for LA batteries but it would work for sealed. If the home has a makeup air system or huge exhaust system all bets are off. Just some thoughts, Bob Ellison -Original Message- From: RE-wrenches [mailto:re-wrenches-boun...@lists.re-wrenches.org] On Behalf Of Drake Sent: Wednesday, October 29, 2014 8:19 PM To: RE-wrenches Subject: Re: [RE-wrenches] Passive Battery Venting Hi Daniel, I typically vent them the way you do, which will allow any small amount of hydrogen out. The customer is absolutely adamant about venting these to the outside. I will cooperate so long as his method doesn't compromise the system through cooling the batteries unnecessarily in the dead of winter. He is a lawyer and came to the conclusion of the need for venting to the outside from reading the NEC which says that sealed batteries require the same amount of ventilation as liquid lead acid batteries. The code also says to vent appropriate to battery technology, so the code says two conflicting things. On the other hand, it doesn't say that liquid electrolyte batteries need to be vented to the outside. They will sure stink if you vent them to the inside. Drake At 09:54 AM 10/29/2014, you wrote: I just re-read the original post Drake. These are AGM batteries. Do you have a belt, suspenders,...then a rocket pack type of client here? We typically vent our AGM boxes with small louver vents top and bottom to allow the batteries to ventilate for cooling purposes
Re: [RE-wrenches] Passive Battery Venting
To do it totally passive you will need a long (tall) pipe up the side of the building, probably painted a dark color to have the sun help warm the tube to help encourage it to vent up, not draw into the building. Put a 180 on the top to keep the rain out and a screen to keep out the bugs. With outside venting the batteries will just draw in room temperature air, if the room is 70 the battery min temp will be 70. If they are in a basement they will naturally draw in outside air, run the vent as high as you can to help prevent that. If you are using a Classic use the relay to turn the fan on and off at a specific battery voltage. Use a brushless fan and a voltage powered relay if no other choice. Do not put the relay in the battery box! Sealed batteries do need to be vented. I have seen them gas when things go wrong, not pleasant. I wouldn't do it without a fan for LA batteries but it would work for sealed. If the home has a makeup air system or huge exhaust system all bets are off. Just some thoughts, Bob Ellison -Original Message- From: RE-wrenches [mailto:re-wrenches-boun...@lists.re-wrenches.org] On Behalf Of Drake Sent: Wednesday, October 29, 2014 8:19 PM To: RE-wrenches Subject: Re: [RE-wrenches] Passive Battery Venting Hi Daniel, I typically vent them the way you do, which will allow any small amount of hydrogen out. The customer is absolutely adamant about venting these to the outside. I will cooperate so long as his method doesn't compromise the system through cooling the batteries unnecessarily in the dead of winter. He is a lawyer and came to the conclusion of the need for venting to the outside from reading the NEC which says that sealed batteries require the same amount of ventilation as liquid lead acid batteries. The code also says to vent appropriate to battery technology, so the code says two conflicting things. On the other hand, it doesn't say that liquid electrolyte batteries need to be vented to the outside. They will sure stink if you vent them to the inside. Drake At 09:54 AM 10/29/2014, you wrote: I just re-read the original post Drake. These are AGM batteries. Do you have a belt, suspenders,...then a rocket pack type of client here? We typically vent our AGM boxes with small louver vents top and bottom to allow the batteries to ventilate for cooling purposes, not H2 concerns. With Regards, Daniel Young, NABCEP Certified PV Installation ProfessionalTM: Cert #031508-90 NABCEP Certified Solar Heating InstallerTM: Cert #SH031409-13 -Original Message- From: RE-wrenches [mailto:re-wrenches-boun...@lists.re-wrenches.org] On Behalf Of Ray Walters Sent: Tuesday, October 28, 2014 11:12 PM To: RE-wrenches Subject: Re: [RE-wrenches] Passive Battery Venting That's why we usually have the batteries in a garage, basement, or out building that is not open to the living space. I've seen some cases of very well sealed and insulated enclosures allowing batteries to over heat, and also build up a lot of acid damaged connections. Boxes I've seen with more air space and less sealing don't get this build up, but you're correct: they do occasionally allow H2S into the surrounding area. R.Ray Walters CTO, Solarray, Inc Nabcep Certified PV Installer, Licensed Master Electrician Solar Design Engineer 303 505-8760 On 10/28/2014 8:10 PM, Jerry Shafer wrote: We do what we can to seal the enclosure so if or when a battery fails and really gasses off the two vents on the same wall regardless of wind direction will vent the gas. If it is not sealed then the gas can travel through out the area this is not advised. ___ List sponsored by Redwood Alliance List Address: RE-wrenches@lists.re-wrenches.org Change listserver email address settings: http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org List-Archive: http://www.mail-archive.com/re-wrenches@lists.re-wrenches.org/maillist.html List rules etiquette: www.re-wrenches.org/etiquette.htm Check out or update participant bios: www.members.re-wrenches.org - No virus found in this message. Checked by AVG - www.avg.com Version: 2012.0.2247 / Virus Database: 4031/7973 - Release Date: 10/29/14 - No virus found in this message. Checked by AVG - www.avg.com Version: 2012.0.2247 / Virus Database: 4031/7973 - Release Date: 10/29/14 ___ List sponsored by Redwood Alliance List Address: RE-wrenches@lists.re-wrenches.org Change listserver email address settings: http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org List-Archive: http://www.mail-archive.com/re-wrenches@lists.re-wrenches.org/maillist.html List rules etiquette: www.re-wrenches.org/etiquette.htm Check out or update participant bios: www.members.re-wrenches.org ___ List sponsored by Redwood Alliance List Address: RE-wrenches@lists.re-wrenches.org Change listserver email address
Re: [RE-wrenches] Passive Battery Venting
Hi drake, I think you need to charge him so you can actually calculate/design the max H2 for any condition and size the vent system for that. And lawyer = conduit Jay Peltz power. On Oct 29, 2014, at 5:19 PM, Drake drake.chamber...@redwoodalliance.org wrote: Hi Daniel, I typically vent them the way you do, which will allow any small amount of hydrogen out. The customer is absolutely adamant about venting these to the outside. I will cooperate so long as his method doesn't compromise the system through cooling the batteries unnecessarily in the dead of winter. He is a lawyer and came to the conclusion of the need for venting to the outside from reading the NEC which says that sealed batteries require the same amount of ventilation as liquid lead acid batteries. The code also says to vent appropriate to battery technology, so the code says two conflicting things. On the other hand, it doesn't say that liquid electrolyte batteries need to be vented to the outside. They will sure stink if you vent them to the inside. Drake At 09:54 AM 10/29/2014, you wrote: I just re-read the original post Drake. These are AGM batteries. Do you have a belt, suspenders,...then a rocket pack type of client here? We typically vent our AGM boxes with small louver vents top and bottom to allow the batteries to ventilate for cooling purposes, not H2 concerns. With Regards, Daniel Young, NABCEP Certified PV Installation ProfessionalTM: Cert #031508-90 NABCEP Certified Solar Heating InstallerTM: Cert #SH031409-13 -Original Message- From: RE-wrenches [mailto:re-wrenches-boun...@lists.re-wrenches.org] On Behalf Of Ray Walters Sent: Tuesday, October 28, 2014 11:12 PM To: RE-wrenches Subject: Re: [RE-wrenches] Passive Battery Venting That's why we usually have the batteries in a garage, basement, or out building that is not open to the living space. I've seen some cases of very well sealed and insulated enclosures allowing batteries to over heat, and also build up a lot of acid damaged connections. Boxes I've seen with more air space and less sealing don't get this build up, but you're correct: they do occasionally allow H2S into the surrounding area. R.Ray Walters CTO, Solarray, Inc Nabcep Certified PV Installer, Licensed Master Electrician Solar Design Engineer 303 505-8760 On 10/28/2014 8:10 PM, Jerry Shafer wrote: We do what we can to seal the enclosure so if or when a battery fails and really gasses off the two vents on the same wall regardless of wind direction will vent the gas. If it is not sealed then the gas can travel through out the area this is not advised. ___ List sponsored by Redwood Alliance List Address: RE-wrenches@lists.re-wrenches.org Change listserver email address settings: http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org List-Archive: http://www.mail-archive.com/re-wrenches@lists.re-wrenches.org/maillist.html List rules etiquette: www.re-wrenches.org/etiquette.htm Check out or update participant bios: www.members.re-wrenches.org - No virus found in this message. Checked by AVG - www.avg.com Version: 2012.0.2247 / Virus Database: 4031/7973 - Release Date: 10/29/14 - No virus found in this message. Checked by AVG - www.avg.com Version: 2012.0.2247 / Virus Database: 4031/7973 - Release Date: 10/29/14 ___ List sponsored by Redwood Alliance List Address: RE-wrenches@lists.re-wrenches.org Change listserver email address settings: http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org List-Archive: http://www.mail-archive.com/re-wrenches@lists.re-wrenches.org/maillist.html List rules etiquette: www.re-wrenches.org/etiquette.htm Check out or update participant bios: www.members.re-wrenches.org ___ List sponsored by Redwood Alliance List Address: RE-wrenches@lists.re-wrenches.org Change listserver email address settings: http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org List-Archive: http://www.mail-archive.com/re-wrenches@lists.re-wrenches.org/maillist.html List rules etiquette: www.re-wrenches.org/etiquette.htm Check out or update participant bios: www.members.re-wrenches.org ___ List sponsored by Redwood Alliance List Address: RE-wrenches@lists.re-wrenches.org Change listserver email address settings: http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org List-Archive: http://www.mail-archive.com/re-wrenches@lists.re-wrenches.org/maillist.html List rules etiquette: www.re-wrenches.org/etiquette.htm Check out or update participant bios: www.members.re-wrenches.org
Re: [RE-wrenches] Passive Battery Venting
I too saw that these were AGMS. The only time excess H venting happens is with severe over voltage for a period of time. How often will this happen? Have any battery wrenches experienced high volume venting of AGM’s? Our experience: There is no NEC requirements for mobile installations. We have installed over 1000 AGM battery banks with only passive venting some with very little air exchange. Out of all our installs over the last 12 years, the only AGM battery venting I know of is when a customer adjusted his charge controller to 3 Vpc. This caused gassing and thermal run away, melting the side of the Deka AGM battery case. For off grid systems, we provide a simple 2” vertical PVC pipe from the battery box for H gas to escape. My opinion: The cost is low and the risk very low if your customer understands the proper operation. Larry On Oct 29, 2014, at 6:54 AM, Daniel Young dyo...@dovetailsolar.com wrote: I just re-read the original post Drake. These are AGM batteries. Do you have a belt, suspenders,...then a rocket pack type of client here? We typically vent our AGM boxes with small louver vents top and bottom to allow the batteries to ventilate for cooling purposes, not H2 concerns. With Regards, Daniel Young, NABCEP Certified PV Installation ProfessionalTM: Cert #031508-90 NABCEP Certified Solar Heating InstallerTM: Cert #SH031409-13 ___ List sponsored by Redwood Alliance List Address: RE-wrenches@lists.re-wrenches.org Change listserver email address settings: http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org List-Archive: http://www.mail-archive.com/re-wrenches@lists.re-wrenches.org/maillist.html List rules etiquette: www.re-wrenches.org/etiquette.htm Check out or update participant bios: www.members.re-wrenches.org
Re: [RE-wrenches] Passive Battery Venting
Hi Daniel, I typically vent them the way you do, which will allow any small amount of hydrogen out. The customer is absolutely adamant about venting these to the outside. I will cooperate so long as his method doesn't compromise the system through cooling the batteries unnecessarily in the dead of winter. He is a lawyer and came to the conclusion of the need for venting to the outside from reading the NEC which says that sealed batteries require the same amount of ventilation as liquid lead acid batteries. The code also says to vent appropriate to battery technology, so the code says two conflicting things. On the other hand, it doesn't say that liquid electrolyte batteries need to be vented to the outside. They will sure stink if you vent them to the inside. Drake At 09:54 AM 10/29/2014, you wrote: I just re-read the original post Drake. These are AGM batteries. Do you have a belt, suspenders,...then a rocket pack type of client here? We typically vent our AGM boxes with small louver vents top and bottom to allow the batteries to ventilate for cooling purposes, not H2 concerns. With Regards, Daniel Young, NABCEP Certified PV Installation ProfessionalTM: Cert #031508-90 NABCEP Certified Solar Heating InstallerTM: Cert #SH031409-13 -Original Message- From: RE-wrenches [mailto:re-wrenches-boun...@lists.re-wrenches.org] On Behalf Of Ray Walters Sent: Tuesday, October 28, 2014 11:12 PM To: RE-wrenches Subject: Re: [RE-wrenches] Passive Battery Venting That's why we usually have the batteries in a garage, basement, or out building that is not open to the living space. I've seen some cases of very well sealed and insulated enclosures allowing batteries to over heat, and also build up a lot of acid damaged connections. Boxes I've seen with more air space and less sealing don't get this build up, but you're correct: they do occasionally allow H2S into the surrounding area. R.Ray Walters CTO, Solarray, Inc Nabcep Certified PV Installer, Licensed Master Electrician Solar Design Engineer 303 505-8760 On 10/28/2014 8:10 PM, Jerry Shafer wrote: We do what we can to seal the enclosure so if or when a battery fails and really gasses off the two vents on the same wall regardless of wind direction will vent the gas. If it is not sealed then the gas can travel through out the area this is not advised. ___ List sponsored by Redwood Alliance List Address: RE-wrenches@lists.re-wrenches.org Change listserver email address settings: http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org List-Archive: http://www.mail-archive.com/re-wrenches@lists.re-wrenches.org/maillist.html List rules etiquette: www.re-wrenches.org/etiquette.htm Check out or update participant bios: www.members.re-wrenches.org - No virus found in this message. Checked by AVG - www.avg.com Version: 2012.0.2247 / Virus Database: 4031/7973 - Release Date: 10/29/14 - No virus found in this message. Checked by AVG - www.avg.com Version: 2012.0.2247 / Virus Database: 4031/7973 - Release Date: 10/29/14 ___ List sponsored by Redwood Alliance List Address: RE-wrenches@lists.re-wrenches.org Change listserver email address settings: http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org List-Archive: http://www.mail-archive.com/re-wrenches@lists.re-wrenches.org/maillist.html List rules etiquette: www.re-wrenches.org/etiquette.htm Check out or update participant bios: www.members.re-wrenches.org ___ List sponsored by Redwood Alliance List Address: RE-wrenches@lists.re-wrenches.org Change listserver email address settings: http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org List-Archive: http://www.mail-archive.com/re-wrenches@lists.re-wrenches.org/maillist.html List rules etiquette: www.re-wrenches.org/etiquette.htm Check out or update participant bios: www.members.re-wrenches.org
[RE-wrenches] Passive Battery Venting
Hello Wrenches, A client wants to use a passive battery venting method with a heat exchanger to the outside for his bank of Full River AGM batteries. Below is a link to one site that recommends this method. Has anyone used this method? http://www.bdbatteries.com/hydrogenventing.phphttp://www.bdbatteries.com/hydrogenventing.php My main concern for about the batteries is that they not get cold and lose capacity during the short days when storage is most needed. He would also like to connect the terminals inside the box to a pass through jumper http://www.bdbatteries.com/lugs.php?id=269 and then run the cables, without conduit, to the inverter. As far as I know, conduit is always required on the battery cables even if fuses are used in the battery box. Has anything changed? Thanks, Drake Drake Chamberlin Athens Electric LLC OH License 44810 CO License 3773 NABCEP Certified Solar PV 740-448-7328 http://athens-electric.com/http://athens-electric.com/ ___ List sponsored by Redwood Alliance List Address: RE-wrenches@lists.re-wrenches.org Change listserver email address settings: http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org List-Archive: http://www.mail-archive.com/re-wrenches@lists.re-wrenches.org/maillist.html List rules etiquette: www.re-wrenches.org/etiquette.htm Check out or update participant bios: www.members.re-wrenches.org
Re: [RE-wrenches] Passive Battery Venting
I have used hi low vents on the same exterior wall with no issues and we have used the firewall through wall terminals there we a pvc box and connect the pipe to that. Every part has a price and it all adds up On Oct 28, 2014 12:54 PM, Drake drake.chamber...@redwoodalliance.org wrote: Hello Wrenches, A client wants to use a passive battery venting method with a heat exchanger to the outside for his bank of Full River AGM batteries. Below is a link to one site that recommends this method. Has anyone used this method? http://www.bdbatteries.com/hydrogenventing.php My main concern for about the batteries is that they not get cold and lose capacity during the short days when storage is most needed. He would also like to connect the terminals inside the box to a pass through jumper http://www.bdbatteries.com/lugs.php?id=269 and then run the cables, without conduit, to the inverter. As far as I know, conduit is always required on the battery cables even if fuses are used in the battery box. Has anything changed? Thanks, Drake Drake Chamberlin *Athens Electric LLC OH License 44810 CO License 3773 NABCEP Certified Solar PV 740-448-7328 740-448-7328 *http://athens-electric.com/ ___ List sponsored by Redwood Alliance List Address: RE-wrenches@lists.re-wrenches.org Change listserver email address settings: http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org List-Archive: http://www.mail-archive.com/re-wrenches@lists.re-wrenches.org/maillist.html List rules etiquette: www.re-wrenches.org/etiquette.htm Check out or update participant bios: www.members.re-wrenches.org ___ List sponsored by Redwood Alliance List Address: RE-wrenches@lists.re-wrenches.org Change listserver email address settings: http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org List-Archive: http://www.mail-archive.com/re-wrenches@lists.re-wrenches.org/maillist.html List rules etiquette: www.re-wrenches.org/etiquette.htm Check out or update participant bios: www.members.re-wrenches.org
Re: [RE-wrenches] Passive Battery Venting
That's an interesting idea, but all the failed designs they illustrate don't show the way we usually do it. We don't even bother with an inlet, as most battery boxes have enough gap around the door to provide intake air, then the exhaust comes off the top with several feet of rise to prevent back drafting. If its in any space that H2s may be a problem (living space), we always add a Zephyr Power vent which has a back draft preventer. Even if the Zephyr fails, there will still be passive air flow up the pipe past the fan. I see 4 problems with their setup: 1) Large Copper pipe is really expensive, and steel is hard to work with and fittings are expensive. 2) Metal pipe is not only thermally conductive, its also electrically conductive. I try to avoid unnecessary conductors in the battery box. 3) Metal pipe will corrode when exposed to H2S and battery acid. That's why we always use plastic. 4) Their suggested pipe size (1 outside pipe) are way too small to provide venting for any more than a couple of golf cart batteries. Basically, heat exchanger = good idea, but their version = not. As for the battery pass through connectors: they seem to be adding unnecessary connections, and would also prevent using conduit. I'd guess they're not UL listed, so that whole idea is also code compliant. Duct seal will prevent the H2S from going up the conduit into the DC load center. They're trying to seal the box too much; the only time you could actually have an explosive build up of H2S is if you sealed every gap on the battery box. I think its easier and safer to keep the gaps, and if your venting fails, at least it won't blow up or over heat. R.Ray Walters CTO, Solarray, Inc Nabcep Certified PV Installer, Licensed Master Electrician Solar Design Engineer 303 505-8760 On 10/28/2014 4:28 PM, Drake wrote: Hello Wrenches, A client wants to use a passive battery venting method with a heat exchanger to the outside for his bank of Full River AGM batteries. Below is a link to one site that recommends this method. Has anyone used this method? http://www.bdbatteries.com/hydrogenventing.php http://www.bdbatteries.com/hydrogenventing.php My main concern for about the batteries is that they not get cold and lose capacity during the short days when storage is most needed. He would also like to connect the terminals inside the box to a pass through jumper http://www.bdbatteries.com/lugs.php?id=269 http://www.bdbatteries.com/lugs.php?id=269 and then run the cables, without conduit, to the inverter. As far as I know, conduit is always required on the battery cables even if fuses are used in the battery box. Has anything changed? Thanks, Drake Drake Chamberlin /Athens Electric LLC OH License 44810 CO License 3773 NABCEP Certified Solar PV 740-448-7328 /http://athens-electric.com/ ___ List sponsored by Redwood Alliance List Address: RE-wrenches@lists.re-wrenches.org Change listserver email address settings: http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org List-Archive: http://www.mail-archive.com/re-wrenches@lists.re-wrenches.org/maillist.html List rules etiquette: www.re-wrenches.org/etiquette.htm Check out or update participant bios: www.members.re-wrenches.org ___ List sponsored by Redwood Alliance List Address: RE-wrenches@lists.re-wrenches.org Change listserver email address settings: http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org List-Archive: http://www.mail-archive.com/re-wrenches@lists.re-wrenches.org/maillist.html List rules etiquette: www.re-wrenches.org/etiquette.htm Check out or update participant bios: www.members.re-wrenches.org
Re: [RE-wrenches] Passive Battery Venting
We do what we can to seal the enclosure so if or when a battery fails and really gasses off the two vents on the same wall regardless of wind direction will vent the gas. If it is not sealed then the gas can travel through out the area this is not advised. On Oct 28, 2014 4:06 PM, Ray Walters r...@solarray.com wrote: That's an interesting idea, but all the failed designs they illustrate don't show the way we usually do it. We don't even bother with an inlet, as most battery boxes have enough gap around the door to provide intake air, then the exhaust comes off the top with several feet of rise to prevent back drafting. If its in any space that H2s may be a problem (living space), we always add a Zephyr Power vent which has a back draft preventer. Even if the Zephyr fails, there will still be passive air flow up the pipe past the fan. I see 4 problems with their setup: 1) Large Copper pipe is really expensive, and steel is hard to work with and fittings are expensive. 2) Metal pipe is not only thermally conductive, its also electrically conductive. I try to avoid unnecessary conductors in the battery box. 3) Metal pipe will corrode when exposed to H2S and battery acid. That's why we always use plastic. 4) Their suggested pipe size (1 outside pipe) are way too small to provide venting for any more than a couple of golf cart batteries. Basically, heat exchanger = good idea, but their version = not. As for the battery pass through connectors: they seem to be adding unnecessary connections, and would also prevent using conduit. I'd guess they're not UL listed, so that whole idea is also code compliant. Duct seal will prevent the H2S from going up the conduit into the DC load center. They're trying to seal the box too much; the only time you could actually have an explosive build up of H2S is if you sealed every gap on the battery box. I think its easier and safer to keep the gaps, and if your venting fails, at least it won't blow up or over heat. R.Ray Walters CTO, Solarray, Inc Nabcep Certified PV Installer, Licensed Master Electrician Solar Design Engineer303 505-8760 On 10/28/2014 4:28 PM, Drake wrote: Hello Wrenches, A client wants to use a passive battery venting method with a heat exchanger to the outside for his bank of Full River AGM batteries. Below is a link to one site that recommends this method. Has anyone used this method? http://www.bdbatteries.com/hydrogenventing.php My main concern for about the batteries is that they not get cold and lose capacity during the short days when storage is most needed. He would also like to connect the terminals inside the box to a pass through jumper http://www.bdbatteries.com/lugs.php?id=269 and then run the cables, without conduit, to the inverter. As far as I know, conduit is always required on the battery cables even if fuses are used in the battery box. Has anything changed? Thanks, Drake Drake Chamberlin *Athens Electric LLC OH License 44810 CO License 3773 NABCEP Certified Solar PV 740-448-7328 740-448-7328 *http://athens-electric.com/ ___ List sponsored by Redwood Alliance List Address: RE-wrenches@lists.re-wrenches.org Change listserver email address settings:http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org List-Archive: http://www.mail-archive.com/re-wrenches@lists.re-wrenches.org/maillist.html List rules etiquette:www.re-wrenches.org/etiquette.htm Check out or update participant bios:www.members.re-wrenches.org ___ List sponsored by Redwood Alliance List Address: RE-wrenches@lists.re-wrenches.org Change listserver email address settings: http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org List-Archive: http://www.mail-archive.com/re-wrenches@lists.re-wrenches.org/maillist.html List rules etiquette: www.re-wrenches.org/etiquette.htm Check out or update participant bios: www.members.re-wrenches.org ___ List sponsored by Redwood Alliance List Address: RE-wrenches@lists.re-wrenches.org Change listserver email address settings: http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org List-Archive: http://www.mail-archive.com/re-wrenches@lists.re-wrenches.org/maillist.html List rules etiquette: www.re-wrenches.org/etiquette.htm Check out or update participant bios: www.members.re-wrenches.org
Re: [RE-wrenches] Passive Battery Venting
I do agree steel and copper/brass is to expensive for the possible return. On Oct 28, 2014 4:10 PM, Jerry Shafer jerrysgarag...@gmail.com wrote: We do what we can to seal the enclosure so if or when a battery fails and really gasses off the two vents on the same wall regardless of wind direction will vent the gas. If it is not sealed then the gas can travel through out the area this is not advised. On Oct 28, 2014 4:06 PM, Ray Walters r...@solarray.com wrote: That's an interesting idea, but all the failed designs they illustrate don't show the way we usually do it. We don't even bother with an inlet, as most battery boxes have enough gap around the door to provide intake air, then the exhaust comes off the top with several feet of rise to prevent back drafting. If its in any space that H2s may be a problem (living space), we always add a Zephyr Power vent which has a back draft preventer. Even if the Zephyr fails, there will still be passive air flow up the pipe past the fan. I see 4 problems with their setup: 1) Large Copper pipe is really expensive, and steel is hard to work with and fittings are expensive. 2) Metal pipe is not only thermally conductive, its also electrically conductive. I try to avoid unnecessary conductors in the battery box. 3) Metal pipe will corrode when exposed to H2S and battery acid. That's why we always use plastic. 4) Their suggested pipe size (1 outside pipe) are way too small to provide venting for any more than a couple of golf cart batteries. Basically, heat exchanger = good idea, but their version = not. As for the battery pass through connectors: they seem to be adding unnecessary connections, and would also prevent using conduit. I'd guess they're not UL listed, so that whole idea is also code compliant. Duct seal will prevent the H2S from going up the conduit into the DC load center. They're trying to seal the box too much; the only time you could actually have an explosive build up of H2S is if you sealed every gap on the battery box. I think its easier and safer to keep the gaps, and if your venting fails, at least it won't blow up or over heat. R.Ray Walters CTO, Solarray, Inc Nabcep Certified PV Installer, Licensed Master Electrician Solar Design Engineer303 505-8760 On 10/28/2014 4:28 PM, Drake wrote: Hello Wrenches, A client wants to use a passive battery venting method with a heat exchanger to the outside for his bank of Full River AGM batteries. Below is a link to one site that recommends this method. Has anyone used this method? http://www.bdbatteries.com/hydrogenventing.php My main concern for about the batteries is that they not get cold and lose capacity during the short days when storage is most needed. He would also like to connect the terminals inside the box to a pass through jumper http://www.bdbatteries.com/lugs.php?id=269 and then run the cables, without conduit, to the inverter. As far as I know, conduit is always required on the battery cables even if fuses are used in the battery box. Has anything changed? Thanks, Drake Drake Chamberlin *Athens Electric LLC OH License 44810 CO License 3773 NABCEP Certified Solar PV 740-448-7328 740-448-7328 *http://athens-electric.com/ ___ List sponsored by Redwood Alliance List Address: RE-wrenches@lists.re-wrenches.org Change listserver email address settings:http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org List-Archive: http://www.mail-archive.com/re-wrenches@lists.re-wrenches.org/maillist.html List rules etiquette:www.re-wrenches.org/etiquette.htm Check out or update participant bios:www.members.re-wrenches.org ___ List sponsored by Redwood Alliance List Address: RE-wrenches@lists.re-wrenches.org Change listserver email address settings: http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org List-Archive: http://www.mail-archive.com/re-wrenches@lists.re-wrenches.org/maillist.html List rules etiquette: www.re-wrenches.org/etiquette.htm Check out or update participant bios: www.members.re-wrenches.org ___ List sponsored by Redwood Alliance List Address: RE-wrenches@lists.re-wrenches.org Change listserver email address settings: http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org List-Archive: http://www.mail-archive.com/re-wrenches@lists.re-wrenches.org/maillist.html List rules etiquette: www.re-wrenches.org/etiquette.htm Check out or update participant bios: www.members.re-wrenches.org
Re: [RE-wrenches] Passive Battery Venting
That's why we usually have the batteries in a garage, basement, or out building that is not open to the living space. I've seen some cases of very well sealed and insulated enclosures allowing batteries to over heat, and also build up a lot of acid damaged connections. Boxes I've seen with more air space and less sealing don't get this build up, but you're correct: they do occasionally allow H2S into the surrounding area. R.Ray Walters CTO, Solarray, Inc Nabcep Certified PV Installer, Licensed Master Electrician Solar Design Engineer 303 505-8760 On 10/28/2014 8:10 PM, Jerry Shafer wrote: We do what we can to seal the enclosure so if or when a battery fails and really gasses off the two vents on the same wall regardless of wind direction will vent the gas. If it is not sealed then the gas can travel through out the area this is not advised. ___ List sponsored by Redwood Alliance List Address: RE-wrenches@lists.re-wrenches.org Change listserver email address settings: http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org List-Archive: http://www.mail-archive.com/re-wrenches@lists.re-wrenches.org/maillist.html List rules etiquette: www.re-wrenches.org/etiquette.htm Check out or update participant bios: www.members.re-wrenches.org
