Question for RF

[ricicle]

Rob, I noticed from another post you have a Metrel Easitest as I do.

Do you get differing results on your RCD tests.When I do the RCD auto test I always get 38mS for 1x and 9mS for 5x for every RCD I have tested.I havn't tried it on manual and yes the meter is calibrated

 

[ricicle]

Are you hibernating Rob?

 

[RF Lighting]

Hi

Not quite hibernating, but as good as. I'm working stupid long hours at the moment


I have not had the meter all that long, but I do get differing readings for RCD tests.

I think securespark has the same tester aswell.

Seems a bit odd that it is the same every time. Is it the same for both sides of the sine wave?

 

[securespark]

Yes, I get a wide variety of readings. Are the RCD's the same brand? I guess not!!

I often test RCD's from a socket outlet.I know that's not the recommended method.

If that fails, I then test in isolation.

The only similar readings I get is on the modern MEM RCD's (is it the 80/100HE?? centre trip position) on the 2nd 5x test (RCD test number 6), where, unless I test the RCD in isolation, I often get a reading of > 40ms.

Older Wylex RCD's often come up with the same reading on both sides of the s/w. One time, I even got one Wylex RCD that came up with >300, >300, 9, 9, 9, 9.

 

[ricicle]

The RCBOs I have been testing recently are in our new factory so they are new and are Square D KQ C32.I have a couple of Powerbreaker RCD sockets to test tomorrow so will let you know the results.

Cheers Guys

 

[securespark]

It is not set in stone, but with stuff from the same mfr, you often get identical (or near identical) results, but not always!

I await your results with baited breath...

 

[ricicle]

Well it seems that RCBOs from the same manufacturer do operate within the same time.I have tested about ten KQ RCBOs recently and they all tripped in exactly the same time (38ms and 9ms) for both halves of the cycle.
Today I tested two Powerbreaker RCD sockets and the results were as follows:-

1) >300, >300, 25, 25, 14, 14

2) >300, >300, 25, 24, 14, 14

The RCBOs/RCD sockets of the same makes must be manufactured to such exact tolerances that even their mechanics allow them to operate in almost identical times, even to within a milli-second or so!

 

[Spark123]

Thats quick for the square D KQ ones, the one I replaced in the theatre not so long back was 100ms> at I, sub 40ms for 5I. I'll take the mft with me next time I go and get some better figures.

 

[securespark]

OOI, ricicle, did you test the RCBO's in isolation or from a socket outlet/ circuit?

I know with my Alphatek sometimes if there is other appliances in circuit, it can affect the readings, especially the ramp result. If you do a ramp test in isolation, the reading is appreciably higher than if you take the reading from a socket outlet with other appliances in circuit.

Also, if you do a 1/2 x test from a socket outlet, it can trip the RCD. When you test in isolation, you find the RCD is good.

This points to a faulty appliance or wiring.

I have used this cheat to track down a few rogue appliances or suspect wiring in the past!

 

[ricicle]

OOI, ricicle, did you test the RCBO's in isolation or from a socket outlet/ circuit?

I tested the RCBOs in isolation while I had the cables out for the ring continuity/IR tests.

 

[ebee]

If you test an RCD which is a live test then no other equipment should be connected as it can vary the trip times (up or down)

 

[securespark]

If you test an RCD which is a live test then no other equipment should be connected as it can vary the trip times (up or down)

I know with my Alphatek sometimes if there is other appliances in circuit, it can affect the readings