motomaster eliminator 1750W Fault light on, but ... weird

If connected to a good 12v source, fault light lights up the moment the inverter is turned on and no power to outlets, however, if I plug in a drill with trigger on, then turn on inverter, the drill runs and no fault light. When I stop the drill, fault light comes on and there is no power at the outlets.

Board label: Xantrex International (c) 2001 442-0097-98-01 Rev. 2

All auto style fuses appear to be intact and there are no obvious burn areas or fried components on the board.

Searching for ideas...

Thanks in advance for any suggestions.

Hi: I also have similar problem, fault light when turn on. Have not tried connecting tool and turning on pressing trigger.

I am looking for equipment schematic (motomaster eliminator 1750W)

Pablo

...edit2...
It seems you have an inverter not a battery charger, so low ESR car battery or with alternator on is essential for reliable operation. If there is a bad cell, then regulation may be poor.
...end edit2....
I suspect it is detecting an overvoltage transient, perhaps due to a noise suppression cap failing open.

I would consider adding a small Film X2 rated Panasonic cap inserted input the outlet and if that works, hard-wire inside. I would consider 0.01 to 0.1 uF. 600Vac or more X2 rated. These tend to to generate square wave RMS AC power and must have some sort of transient filtering.


Compute the impedance of the cap to be less than rated power, voltage, f to guarantee no OCP is triggered and thus suppress the OVP that I suspect is false detected.

Zc= 1/(ωC)
U²/R=P for rated load R and Power in Watts





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Is it possible that it is a Xantrex, with Canadian Tire logo?

I could not find this model on their website and if it has no diagnostics to isolate the fault, this speaks poorly of CT's selection criteria. Xantrex makes good products and these are their specs. of similar units.
Each unit has the ability to recall and clear fault codes.

No load (OV) might just be as bad as overload (OC)


aside useful info
https://www.xantrex.com/documents/Tech-Doctor/Universal/Tech4-Universal.pdf

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from Xantrex... Problem Loads
Very Small Loads If the power consumed by a device is less than the threshold of the Load Sense
mode circuitry, the device will not run. See the Configure PROsine—Basic
Menu on page 4–7 and the Configure PROsine—Advanced Menu on page 4–8
for ways to solve this problem. Most likely the solution will be to defeat the Load
Sense mode feature