Hager RCD faliure

woz · Oct 2, 2012

Hi all,
I had a Hager CD282U 80A RCD fitted to a Tenby consumer unit. Yesterday I had the electric oven on, the computer, plasma and was playing loud music through the AV amplifier. The sockets went off followed by a buzzing from the consumer unit. The sockets then came back on, each socket in the house buzzed then went off. I went to the consumer unit, carefully took the cover off and saw the neutral connection at the bottom right of the Hager RCD was sparking. All the connections to the RCD were very tight, it'd just been put in 2 months ago to replace a 63A tenby unit. No fuses had tripped.

I've removed the RCD now and put the Tenby back in. The plastic surrounding the connection on the Hager is melted and the clamp is blackened as was the crimped end on the neutral cable. Could it be that I was drawing too much power at the time and the RCD catastrophically failed? I was under the impression that Hager were quite good.

mechelec · Oct 2, 2012

Sounds like a bad connection, you say the connection was tight but I have known the clamp screw to be welded with the arcing. You cant move it but still pull the cable out.

woz · Oct 2, 2012

It does sound like that but it was tight, I know because I put it in myself. The crimp is also tight on cable. You're right, it was very difficult to unscrew with the arcing.

polo1 · Oct 2, 2012

I can't imagine any way you could possibly have been drawing too much current. Either a poor connection or a faulty RCD would be my guess. I like Hager and use them a lot. Have your wholesaler send it back to Hager for comment (and you may get another foc too).

Regards

Bobster · Oct 2, 2012

woz said:
It does sound like that but it was tight, I know because I put it in myself. The crimp is also tight on cable. You're right, it was very difficult to unscrew with the arcing.

What were the results of the ramp test when you installed it?

imago · Oct 2, 2012

polo1 said:
I can't imagine any way you could possibly have been drawing too much current. Either a poor connection or a faulty RCD would be my guess. I like Hager and use them a lot. Have your wholesaler send it back to Hager for comment (and you may get another foc too).

Regards

You might struggle with that, warranty and insurance only apply if you fit RCDs, MCBs, RCBOs etc into a board made by the same manufacturer.