Never mind. This one need to be installed in the circuit. Not sure of the advantage other than isolation.
From: ch...@wbmfg.com Sent: Friday, June 16, 2017 12:32 PM To: af@afmug.com Subject: Re: [AFMUG] PacketFlux shunts https://www.sparkfun.com/products/8882 From: Bill Prince Sent: Friday, June 16, 2017 12:08 PM To: af@afmug.com Subject: Re: [AFMUG] PacketFlux shunts A Hall effect sensor would be the gold standard for a non-intrusive way to sense current. I looked at cobbling together something on my own, but it was more complicated than I anticipated. bp <part15sbs{at}gmail{dot}com> On 6/16/2017 11:01 AM, George Skorup wrote: All we've ever bought are the 10A version. They read accurate enough to see when a 1/2 or 1A DC-UPS is charging as well as 3-7A the other direction when the load is running on battery. Typical 24 and 48VDC systems with <200W load. And then me not paying attention with the Traco BCMU's 12VDC. Using the 2-relay/3-switch module, remotely I could see that the "Batt OK" contact was open after power came back up at the site at like 4am and still open around 8am. Since the site went down sooner than expected, I figured either the battery fuse on the BCM blew or it was sensing some other issue. So I get there and put my clamp-on ammeter on it and zero current. Two fused 20AH batteries in parallel both sitting at 13.1 volts. OK, WTF. Then it all made sense with the shunt. Another thought I had is... what about Hall effect sensors? Could you do a module for that? That would be pretty cool. On 6/16/2017 11:00 AM, Forrest Christian (List Account) wrote: There will likely be a 20A shunt in our future. I'm in the process of redesigning these so that they're less expensive to build since the existing design is being sold at or possibly below cost. I'm trying to end up with a 20A shunt as a result but I don't know for sure if this will happen. On Jun 15, 2017 5:47 PM, "George Skorup" <george.sko...@cbcast.com> wrote: Forrest, Would you be willing to make a 20A shunt? Would the traces on your current design handle it? Reason I'm asking is... I'm stupid. I had a 10A shunt on the batt negative side of a Traco BCMU360. Didn't occur to me that 230 watts @ ~12VDC can get up to 20A. So the shunt went kaput after about 25 minutes and the site went down. Not a problem at most other sites with less load. This one happens to be the most heavily loaded with two Trango ApexPlus, various APs and PTPs plus the DC-DC inefficiencies.
