Maynuo M9712 zero current measured value (output off)

[manupthehills]

I own an M9712 electronic load that I'm about to calibrate (adjust).
The main board doesn't look too clean and I measure 32uA when 12V are applied to the input. This current is measured when the output is off.

Not sure if this is a normal value for this instrument or if this is the result of the dirty PCB...
Anyone owning this model can please run the same measure and reply with the value?

Thanks 

[Tjuurko]

And if you turn off the voltage measurement circuit?
MENU -> SYSTEM SET -> TERMINAL SET -> BACK

[Pinkus]

Same with my M9712: I measured 33µA. Even if the unit is fully switched off (main power) it takes 27 µA.
... and mine is definitely clean inside!

[Tjuurko]

In my case (M9812), all parasitic consumption goes to the voltage measurement circuit (R=365k).
60V - 164 µA
50V - 137 µA
40V - 110 µA
...
10V - 27.2 µA

When switching to the rear panel (no wires connected to the rear panel), the consumption is 0.

[manupthehills]

Thank you guys! That saved me a lot of work. 

I also measured the input current at the front terminals in the other two configurations:
- 12V front terminals: 32.6uA
- 12V rear terminals: 120nA
- 12V mains disconnected: 27.7uA