RCD testing

[rushik77]

I have a building manager who insists that the RCD test needs to be performed on the output of the dimmer that is fed from an RCD. When dimming the RCD does not trip and so he says the dimmer is affecting the RCD and making the whole installation unsafe.

How do I convince him the test needs to be performed at the output of the RCD only???? HELP!!

 

[securespark]

Refer him to the manufacturer of the RCD.

Find the number for the manufacturer, get hold of the tech dept & put him onto them. Ask him to verify with them the correct procedure for testing RCD's/ RCBO's.

 

[RF Lighting]

Is this a theatrical dimmer type setup by any chance?

 

[Adam_151]

While RCD tests are ideally performed at the device in isolation, the fact that it fails when you test it after the dimmer worries me slightly, it could simply be that the dimmer is confusing the instrument... Try dimming a few lanterns and putting RCD tester before dimmer pack. If that stops it tripping (but it trips fine wih no load) then you have the wrong type of RCD... is it a type AC?

 

[Spark123]

I could bore you with the technical stuff of how a stage dimmer clips the sine wave to create a different waveform dependent on the input signal, however as far as you need to know the sine wave from a dimmer is clipped hence will confuse the hell out of any test equipment manufactured to work on 50Hz sine wave AC.
A type AC RCD should be fine, even on dimmed circuits as they are still alternating without a DC pulse (owing to an inductor in series with the load).