RCBO problem

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Has anyone had the following problem ? Testing a rewire we did last week, CU is a new type Steeple ( Made for Denmans by Crabtree) with a mixture of RCBOs at one end and a traditional RCD at the other , guarding two circuits.

Problem, reading the Zs with my Kewtech loop imp. tester is OK on the traditional RCD ,as usual, but trips the RCBOs which we have only just started to fit. :_|

Deke

 
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Deke

What current does kewtech loop tester put down circuit. The old robin loop testers with d-lok trip electronic RCBO'S that is why I stopped using them.

I thought the kewtech ones used the same principle.

Batty

 

sirsparkabit

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Has anyone had the following problem ? Testing a rewire we did last week, CU is a new type Steeple ( Made for Denmans by Crabtree) with a mixture of RCBOs at one end and a traditional RCD at the other , guarding two circuits.Problem, reading the Zs with my Kewtech loop imp. tester is OK on the traditional RCD ,as usual, but trips the RCBOs which we have only just started to fit. :_|

Deke
Tested the Basics range similar configuration with no probs with me 1552 not tried the steeple ones though.

 
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DekeWhat current does kewtech loop tester put down circuit. The old robin loop testers with d-lok trip electronic RCBO'S that is why I stopped using them.

I thought the kewtech ones used the same principle.

Batty
I don't know what current, can't be 30mA or the normal would trip , I bought the Kewtech because its not supposed to trip RCDs.

Deke

 

paulh

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Shouldn't it be less than 15ma as anything above this is allowable to trip a 30ma rcd?

 

paulh

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I can't imagine the rules would change because its a rcbo. 15ma is normally the max so as not to trip rcd's(30ma). rcbo's are supposed to replace rcd's so should use the same rules you would think.

 
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Hi, KME , I've had to link the rcds for yonks because my original tester tripped them. It had been driving me up the wall and now we are fitting RCBOs everywhere I levered open my wallet and bought this Kewtech no tripper. Looks like a waste of dosh !!

Deke

 

Nicky Tesla

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Hi, KME , I've had to link the rcds for yonks because my original tester tripped them. It had been driving me up the wall and now we are fitting RCBOs everywhere I levered open my wallet and bought this Kewtech no tripper. Looks like a waste of dosh !!Deke
are u putting a test lead on the neutral as well (3 test leads)

 
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the RCBOs are only single pole and a lot of meters WILL trip them as they only balance the N and dont limit the leakage(measurement) current to earth.either fit DP RCBOs or link them out.

HTH.
Or buy a meter that doesn't trip them. Fluke 1600 range don't.

Batty

 

septiclecky

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DekeWhat current does kewtech loop tester put down circuit. The old robin loop testers with d-lok trip electronic RCBO'S that is why I stopped using them.

I thought the kewtech ones used the same principle.

Batty
Kewtech are the old Robin testers, Mangement bought the rights to Robin testers when Fluke bought Robin and stopped making Robin testers.

 
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the RCBOs are only single pole and a lot of meters WILL trip them as they only balance the N and dont limit the leakage(measurement) current to earth.either fit DP RCBOs or link them out.

HTH.
Oh Blimey Steps, I'm sick and tired of linking 'em out, thought I was the Bees Knees with my new non trip tester. :_|

Deke

 

Clouseau

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My Robin 1630 does not usually trip most RCDs but sometimes it will tell you D-lok is not available, but try it again 10 seconds later and it is ok.

It always trips MEM2000 RCDs

 

PC Electrics

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I've never had any problems with my Megger 1552 tripping either RCDs or RCBOs. However, I have recently come across a number of faulty (new) Crabtree RCDs and RCBOs:

* won't switch back on after being tripped unless tapped or left a while

* won't trip when button pressed

* random tripping on a perfect circuit

* failing the standard tests - usually at 5x

* very low ramp figure (less than 15mA).

I think the problems are mostly to do with the internal mechanics and I only use Crabtree now where there is no choice because the existing board is Crabtree. Otherwise I won't touch them.

Consider the possibility the RCBOs are faulty - try a ramp test.

 

Battersby

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If you`re in total control of the circuit, link out the RCBo for testing purposes.
No, no, no, no, noooooooooooo!!!!!!

NEVER do this. Never.

I am shocked and dismayed that three of you think this is acceptable practice.

If you can't measure Zs directly (and why would you want to on a new installation?) then calculate in accordance with Appendix 14.

 

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