That wouldn't be too bad to coil up. 2/pi would be the diameter of a 2'
loop (about 7-1/2 inches). Two loops would be about 3-3/4 inch, and so
on. Three or four loops would make a nice tidy package.
bp
<part15sbs{at}gmail{dot}com>
On 6/16/2017 10:34 AM, ch...@wbmfg.com wrote:
The 100 mV is not a problem. .1 volt/20 amps is .005 ohms.
So, 2 feet of 14 gauge will produce 100 mV at 20 amps.
Just feed it into the SiteMonitor.
Assuming aesthetics are not an issue.
-----Original Message----- From: George Skorup Sent: Friday, June 16,
2017 11:30 AM To: af@afmug.com Subject: Re: [AFMUG] PacketFlux shunts
Because Forrest makes them in a nice little DIN rail package and
designed to work on his SiteMonitor base and modules with a nominal
100mv.
On 6/15/2017 8:07 PM, Chuck McCown wrote:
Assuming they were EXACTLY the same resistance. Otherwise there will
be an uneven division of currents.
I prefer to use #10 wire. 1 foot is .001 ohms. Make your own shunt.
Assuming 20 mV full scale is enough.
20 gauge (which is hard to find) is close to .01 ohms per foot.
However that exceeds the ampacity.
I would be OK with one foot of 14 gauge for a 20 amp shunt. .0025
ohms per foot. that would give you 50 mV full scale.
Of course this assumes you have the room for and don't mind the look
of a coiled up foot of wire.
-----Original Message----- From: Bill Prince
Sent: Thursday, June 15, 2017 4:55 PM
To: af@afmug.com
Subject: Re: [AFMUG] PacketFlux shunts
This may be a bozo approach, but if you took two 10 amp shunts and
connected them in parallel, you would get a 20 amp shunt out of the
deal.
bp
<part15sbs{at}gmail{dot}com>
On 6/15/2017 3:47 PM, George Skorup 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.
