Sir driver06 . . . . .
I had initially started on this MUCH earlier, but then had to break away for more urgent Sattidy tasks.
In the interim I see that . . . der
KIWI . . . meister, has added on his :
My guess would be that the shunt rating is three times the meter setting.
Check the details written on the shunt and compare them to the link on the other side of the board(150,250,500,600,1000).
Both should be the same.
Those statements also mirror my same exact suspicions.
I am now going to go into even further and exacting depth in responding to those two presumable factoids.
Now, with you knowing the necessary facts related to the externally connected ammeter shunt block, as if the proper one is being used.
The use of a known load connected in series with the power source and its remoted shunt should permit you to use a DVM in its . . . probably . . . lowest DC Voltage range, to measure across screw terminals connected to wires 1211 and 1210 . The readout should be in millivolts as directly related to amps then passing thru the completed current curcuit.
If that is then in disagreement with the instruments interpretation of amps passing . . . . .in its being low, as you say . . . .
Then there is need of checking out the instrumnents range scaling.
Lets examine some things . . . .
I initially see that near the left white display LED cluster / pack, PCB midpoint, is an option of AC or DC operation, with a solder blob spread connection now enabling the DC mode.
A short distance down, will be what I think are being three dummy / production change
TA and
Sample and Hold solder pads.
NOW ! . . .My kingdom for the purveyor of the correct relevant info on / as to the cryptic "
TA" mode aspect.
S o o o o o o o . . . . . nowsomewhathoweveranyways . . . . . if you will then look a bit further to the right of that trio of pads, you will see that mode function is being engaged by the pesence of yet another solder blob spread connection at
ANOTHER foil etched
SH mark up . . . with no
TA involvement..
Now . . . for the real MONEY shot . . . . . look at the opposite end of that mentioned TA and SH options stakes and then see the starting off of 100.0 * 60.0 * 50.0 * 25.0 and 15.0 * paired sets of stakes exposed solder to foil pad joints.
Therewith I am fully expecting some series arranged and selected values of surface mount resistors on the unviewable side, to be daisy chained between the sets of stakes for creating range selectors for the differently required millivolt range scales.
Viz . . . .
15mv - 15 Amp . . . . . 25mv - 25 Amp . . . . . 50mv - 50 Amp . . . . . 60mv - 60 Amp and the final
1000mv - 100 Amp, you just need to be sure that you are using the proper remoted current shunt and then push on a jumper plug for the set of stakes related to your required millivolt range.
With your experienced low readings, I am expecting that it is now improperly scaled / jumpered for a 1000mv readout . . . . . . thus the resultant low side error.
Since the other PC board sides view was not being offered . . . .are the below units being the same / correct parts ?
Strip of breakaway Dual Row Header Pins
https://5.imimg.com/data5/CB/UH/MY-21614932/dual-row-pin-header-500x500.jpg
Shorting plug for use between header pins
https://p.globalsources.com/IMAGES/PDT/BIG/951/B1061926951.jpg
I'm expecting use of
Gold flashed pins for weatherability / reliability . . . and expectimg the PROPER installation of a shorting plug across the 60.0 set of pins.
HOWEVER the 1000 range might be a real mystery to affirm . . . without confirmational TESTING . . . .because it could be
with a shorting plug installed at the 1000 set of pins . . .
OR . . .with
NO jumper plug being used on the unit at all !
All . . . . . leading back to the possibility that some production line new hires . . . . . Sally Jean Johnson / or / Missy Ling Ting Tong . . . set up the wrong meter voltage scaling on that unit of yours.
Check the battery.
I'm seeing this unit being direct hard wired into
MAIN system battery via wires 1212/9 and -B1P/9A.
Tha a a a a a a a s s s s s s it . . . . . .
BTW . . .poster . . .what is ? . . . . . this monitored equipment . . . that uses 24VDC . . . . at maybe 200AH instant capability ?
73's de Edd . . . . .
As I am a' seein' it, this a' here . . . Tact . . . thang. . . . . . . is being the capability of convincing people that they know more than they actually do.
.