Ok, thanks for the clarification. On Sat, May 30, 2020, 9:18 AM Dave S <syerd...@gmail.com> wrote:
> Essentially yes, however when you are thinking of the boat's wiring, I > would think of the ground bus as the centre, with the engine connected to > it, rather than the reverse. Think of it a hub or a star - with the > ground bus at the centre. (Google "star grounding") one of those paths > has to finally cross the shunt to be measured. (those loads which are > powered by the house bank) > > That green wire is the ground for the aluminum fuel tank. The rest are > batteries (house 1,2, and start) or engine, plus the shunt. All are at > the same ground potential. On the other side of the shunt is > the smartcharger, the refrigeration unit, the house breaker panel, and > anything else I want to "see" in the BMV 700. Basically anything that > impacts the house bank, (though this does not include the alternator.) > > Dave > > > > On Sat, 30 May 2020 at 08:43, Brian Davis <brianwdavis...@gmail.com> > wrote: > >> Thanks, Dave. I have the same type of shunt that came with the Blue Sea >> panels I'm installing and will have the same monitoring. I see in you pic >> there's a green wire (grounding?) going to the bus along with the blacks >> (negative batteries). So, all of that goes to the same engine connecting >> point and the grounds and negatives share that single point? Just want to >> make sure I completely "get it". >> >> Thanks for all your guys help. >> >> On Sat, May 30, 2020 at 8:21 AM Dave S <syerd...@gmail.com> wrote: >> >>> Agree with Joe's comment. the engine must be grounded but should not >>> be used as your primary grounding point. >>> there are a buncha' good reasons for this. Another thing to consider is >>> providing for an upgrade the battery/power monitoring, for which you may >>> need to install a resistive shunt between the battery and the various >>> grounds you wish to monitor, Here's a photo of the shunt (on the >>> right) and ground bus (left) in my 33-2, you can see the ground bus and >>> various grounds attached, this bus is connected to one side of the shunt, >>> the other side of which is connected to the house breaker panel and the >>> other accessories that are measured by my battery/power consumption >>> monitor. This is the shunt that victron provides with the BMV-700. >>> >>> >>> https://3.bp.blogspot.com/-LeNHHo5kK2k/V5V0MaFJ_cI/AAAAAAAAAkc/VI_Cm3z-Aa0m_dZ9AmlgaeVdXmXQOINkgCLcB/s1600/blog%2Bgrounding%2B2.jpg >>> >>> >>> >>> Dave >>> >>> >>> >>> >>> >>> >>> >>> -- Forwarded message ---------- >>> From: Brian Davis <brianwdavis...@gmail.com> >>> To: cnc-list@cnc-list.com >>> Cc: >>> Bcc: >>> Date: Sat, 30 May 2020 07:32:16 -0400 >>> Subject: Stus-List Grounding >>> Hello everyone, >>> >>> Hope you quarantine projects are going well. >>> >>> I have a question about grounding. I'm currently refitting ALL wiring >>> from scratch on our 1980 Landfall 38. I literally gutted every piece of >>> wire and bought all new Ancor tinned marine cables in every guage you can >>> imagine. She's coming along swimmingly, and I've mapped everything out >>> pretty well in a 8 page layered diagram that I'm happy to email direct to >>> anyone who wants it. It's in PowerPoint and about 8mg. >>> >>> My question about Grounding is if it's ok to use my engine as the >>> grounding point? I'm using the similar area for the Negative connection for >>> the 3 battery banks, but a different bolt to the engine case. Several >>> appliances including the breaker panels, ACR, battery charger, water >>> heater, fuel tank, etc require a ground and I'm using a 6 awg green wire >>> from the engine to a large Blue Sea busbar. Then connected the grounds to >>> it. >>> >>> I've also run a 2awg wire from the mast step to the keel bolt and to one >>> of the stanchion bases from underneath for lightning protection. However I >>> kept that all separated and not connected to the grounding. >>> >>> Make sense? Or am I missing something? Again, happy to send my diagram >>> for review. >>> >>> Regards, >>> Brian >>> South FL >>> >>> >>> >>> ---------- Forwarded message ---------- >>> From: Joe Della Barba <j...@dellabarba.com> >>> To: cnc-list@cnc-list.com >>> Cc: >>> Bcc: >>> Date: Sat, 30 May 2020 07:52:37 -0400 >>> Subject: Re: Stus-List Grounding >>> >>> Don't use the engine for ship's ground. Use one of these: >>> >>> >>> https://www.bluesea.com/products/2127/MaxiBus_250A_BusBar_-_Four_5_16in-18_Studs >>> >>> Your AC ground bus will connect to that ground point as well. Speaking >>> of AC, make sure you have a galvanic isolator. >>> >>> Run ONE ground wire to the engine. You don't want your engine block to >>> be a routine conductor of electricity. >>> >>> Here is your lightning ground conundrum: The old way was to connect all >>> metal together. Coquina came with a ground wire system that connected every >>> single thru-hull, the mast step, the engine and the keel. The problem with >>> that is if the zinc does not work perfectly, you can have electrolysis on a >>> large scale since you have all this metal wired together. I undid all that, >>> no thru-hulls are wired to anything. The mast is wired to a keel bolt with >>> 4 gauge wire. The ship's ground bus is wired to the engine with one ground >>> wire. >>> >>> >>> Joe Coquina >>> On 5/30/2020 7:32 AM, Brian Davis via CnC-List wrote: >>> >>> Hello everyone, >>> >>> Hope you quarantine projects are going well. >>> >>> I have a question about grounding. I'm currently refitting ALL wiring >>> from scratch on our 1980 Landfall 38. I literally gutted every piece of >>> wire and bought all new Ancor tinned marine cables in every guage you can >>> imagine. She's coming along swimmingly, and I've mapped everything out >>> pretty well in a 8 page layered diagram that I'm happy to email direct to >>> anyone who wants it. It's in PowerPoint and about 8mg. >>> >>> My question about Grounding is if it's ok to use my engine as the >>> grounding point? I'm using the similar area for the Negative connection for >>> the 3 battery banks, but a different bolt to the engine case. Several >>> appliances including the breaker panels, ACR, battery charger, water >>> heater, fuel tank, etc require a ground and I'm using a 6 awg green wire >>> from the engine to a large Blue Sea busbar. Then connected the grounds to >>> it. >>> >>> I've also run a 2awg wire from the mast step to the keel bolt and to one >>> of the stanchion bases from underneath for lightning protection. However I >>> kept that all separated and not connected to the grounding. >>> >>> Make sense? Or am I missing something? Again, happy to send my diagram >>> for review. >>> >>> Regards, >>> Brian >>> South FL >>> >>> _______________________________________________ >>> >>> Thanks everyone for supporting this list with your contributions. Each and >>> every one is greatly appreciated. If you want to support the list - use >>> PayPal to send contribution -- https://www.paypal.me/stumurray >>> >>> _______________________________________________ >>> CnC-List mailing list >>> CnC-List@cnc-list.com >>> http://cnc-list.com/mailman/listinfo/cnc-list_cnc-list.com >>> >>> >>> >> >> -- >> Brian Davis >> 1980 C&C Landfall 38 >> "Nina" >> Southeast Florida >> >
_______________________________________________ Thanks everyone for supporting this list with your contributions. Each and every one is greatly appreciated. If you want to support the list - use PayPal to send contribution -- https://www.paypal.me/stumurray
