Lighting circuit not working

[RF Lighting]

.... made by Hager.

With an RCBO it is often difficult to tell without testing if it is tripped by an Earth Leakage fault or an overload.

They will also trip if incorrectly fitted and not properly tested by an incompetent installer.

Just like to add to your list that the device itself could be faulty(although not the case here). I have had to replace 2 Hager Mcbs this month that would not stay in the latched position.

Which range OOI?

 

[dingodeano]

MT106's
One customer was attempting a switch change shorted the fitting and couldn't reset breaker. The other was a lady who 'lost' her upstairs lighting and same again hager breaker would not close.
I used to think hager were quality but now I'm beginning to think they are a bit cheap.

 

[RF Lighting]

The new style ones? We fitted thousands of the ones with black levers when I was doing pub fitting and they always seems quality gear. I've not had many dealings with the new type.

 

[securespark]

I see overloaded and stressed MCB's all the time, mostly 6A ones.

I've seen all sorts of brands too. But I too have seen Hager MT106's recently that have broken down.

In the last couple of years,

Actually.......I've had three failed MCB's in as many years, one Geiwess, one Hager and one GET.

Then earlier this year, another Hager MT106 went down.

A strange one it was.

I went to a property to check out an unrelated issue. As I was leaving, I offered to fit a replacement fitting in the hall.

Before I did, I checked the Zs.

It was high, not a fail for a 6A type B, but a lot higher than I'd expect a fitting 6 feet from a DB to be. I checked other fittings on the same circuit: similar high readings. Readings off sockets were normal.

Then the customer said the lighting suffered a great deal of flickering.

I then isolated the MCB. It seemed to switch off a lot easier, with a lot less force than the other MCB's. On a whim, I changed the MCB.

The Zs dropped like a stone, and other readings on the circuit plummeted too. And when I rang the guy later that month, the flickering had stopped too.

So it seemed the MCB was only just holding but causing flickering as the connection was poor and presumably, because of this poor connection, the Zs was being pushed up too.

EDIT in response to RF's post: the Hager MCB's I've replaced have been the older ones with black switches, not the newer type with wider grey ones. Funnily enough, I've not replaced any new ones yet. Installed 100's of them, though... Famous last words.

 

[boilerfrustration]

I'd just thought I'd point out that the Hager devices have an inbuilt flickering safety feature designed to inform anyone on the stairway that the lights are about to go out and therefore to give him a chance to make his way to the nearest switch. I wonder if it's the flickering combined with the use of halogen bulbs which may be the problem? And I wonder if the flickering can be turned off at the consumer unit?

 

[JohnD]

the Hager devices have an inbuilt flickering safety feature

which devices?

doesn't it cause arcing?

 

[boilerfrustration]

The consumer units.

 

[JohnD]

you mean, the MCBs inside the consumer units?

 

[EFLImpudence]

I'd just thought I'd point out that the Hager devices have an inbuilt flickering safety feature

Please tell us more. Does this work on shower and cooker circuits as well?

designed to inform anyone on the stairway that the lights are about to go out and therefore to give him a chance to make his way to the nearest switch.

What good would that do?

I wonder if it's the flickering combined with the use of halogen bulbs which may be the problem?

I don't know.

And I wonder if the flickering can be turned off at the consumer unit?

Probably not if it is inbuilt.
Would turning off the flickering be the same as turning on the light?

 

[boilerfrustration]

I rang Hager who said that the built in flickering feature for lighting is hardwired into the unit and cannot be switched off. He stressed it was for safety so that anyone walking half way up/down a stairs doesn't get trapped in the dark. He also said it was best to use quality bulbs like osram and philips.

 

[RF Lighting]

That must play havoc with achieving 0.4 second disconnection times

 

[dingodeano]

I changed old style black lever. For new type with inbuilt circuit id label. Never heard of flickering safety feature tho ?

 

[dingodeano]

Although I did google it
http://edmundson-electrical.voltili...=&universe=manufacturer.mannews.brand&id=1071

 

[RF Lighting]

Hmmm that doesn't sound good

 

[Adam_151]

I changed old style black lever. For new type with inbuilt circuit id label. Never heard of flickering safety feature tho ?

I can't imagine that its any intentional design, but I do wonder if perhaps it perhaps happens on occasion...I expect that when the current almost reaches the point at which the magnetic realise operates and the contacts are on the verge of separating, that the force holding them together is very slight indeed.

I recall there being an issue with a piece of machinery following a dist board change at one site. It was on a type 2 breaker before and went back on a type C. Now I can only imagine the type 2 was at the insenstive end of what its allowed to be be, and the C at the most sensitive end, because 50% of the time when the machine started, the breaker tripped off. But on the times it didn't trip, if you were stood near the board it made a bit of noise as the machine started, also interesting was that if you held the breaker, it wouldn't trip... now we all know you can't hold a modern breaker on against a fault. So I reckon just under the current value which causes it to trip, theres a value of current which will make it 'unstable' and it might trip, might not, will perhaps chatter, and just possibly the contacts might fleet briefly?

Or it could just be nonsense, its just my guesswork to explain what I've seen