Identifying Cutout as conventional or electronic

[johnbuckley]

I'm sure I read some how to check if a cutout is an electronic gizmo or conventional true cutout without taking the lid off, but can someone remind me ? Thanks .

 

[nkaminar]

An electronic cutout is a diode that allows the current to only flow in one direction. You may be able to tell using an ohmmeter. The resistance should be high in one direction and low in the other direction. The diode will not turn on unless the voltage is more than about half a volt so it all depends on how many volts your ohmmeter has. Most, if not all, ohmmeters should have enough voltage to push current through the diode.

 

[rotorwrench]

If a person has a modern multi meter, it will have a continuity test feature that beeps if there is continuity. These generally work as a diode tester. It will beep with polarity in the direction of flow but not in the opposite polarity.

If it beeps at all then it is a diode. The function of an electro-mechanical cut out relay requires a voltage just above the battery voltage to get the relay to snap closed and allow current to pass. It will always be open under a test with either an Ohms function or a continuity function.

An open or closed circuit under these tests is not always conclusive since a failed diode may not pass current at all and a stuck closed relay will pass current both ways. Taking the cover off is the best way to tell what it is.