Gremlins

[jon_d]

he would have disconnected all the cables from the load side of the shunt and checked the accuracy of the BMV ....

Or simply measured the voltage across the shunt. That would be faster and easier.

[T1 Terry]

he would have disconnected all the cables from the load side of the shunt and checked the accuracy of the BMV ....

Or simply measured the voltage across the shunt. That would be faster and easier.

ummmm...... 500 amps = 50mv, do you really think the average multimeter will pick up 10 amps worth accurately? If you disconnect the load side of the shunt you can select "Zero" from the scrolling menu and reset the BMV so it knows what voltage zero amps actually represents, allowing for any stray induced current in the circuitry.

Anyway, had a phone call from the latest person trying to sort out what was wrong with the system. Turns out more than one person has been fiddling with the system but not having a clue just what they were doing. After getting the run down on what wires were where, the wires on the solid state relay control side were reversed, the control wire from the PL 20 was moved to the wrong position and both 470 ohm 5W resistor has been fried, and that was why the system didn't work. It's anyone's guess what other setting have been fiddled with ........

T1 Terry

[Mrcoolabah1au]

All fixed have ordered new capacitors for pl20 and one for the timer coming from Melbourne so be here shortly

[jon_d]

Doesn't everyone have one of these?

https://www.aliexpress.com/item/1005004341924689.html?

At the 50mv range, it measure down to 1uV. Not a bad price at $160 +GST

[T1 Terry]

All fixed have ordered new capacitors for pl20 and one for the timer coming from Melbourne so be here shortly

Resistors, but we know what you meant, good to hear.

T1 Terry

[T1 Terry]

Doesn't everyone have one of these?

https://www.aliexpress.com/item/1005004341924689.html?

At the 50mv range, it measure down to 1uV. Not a bad price at $160 +GST

I'm gunna go with "No" on that one Jon, a very select few would need something that measured to that level of accuracy and useless in the automotive field for in vehicle testing with up to 500mv background noise on average and maybe 400v to 10,000v spikes on the ignition circuit and anything directly powered from there ...... yes, modern spark ignition engines will kill if even the primary coil pack wires are touched, that is why they are hidden away from silly fingers and the coil goes directly onto the spark plug

T1 Terry

[supersparky]

Doesn't everyone have one of these?

https://www.aliexpress.com/item/1005004341924689.html?

At the 50mv range, it measure down to 1uV. Not a bad price at $160 +GST

I've got quite a few toys for playing with and testing electrical stuff, but I don't have one of them.