Shutter Relay Tripping ELCB

Hi All,

Has anyone had an issue with the shutter relay tripping out an ELCB? I have two units, and when I connected the second unit, simply hitting the UP or DOWN button causes the issue. This is true also if the relay outputs are disconnected and only the 240V supply is connected to the unit.

The only way I got it all working was to remove the supply from the second shutter relay.

Cheers,

Paul

 

Sounds like you need to check the wiring.

There is a good chance that you have mixed neutral on the circuit. This will trip the RCD straight away. I doubt it is the shutter relay at all.

Double check the wiring and then check again.

If it still trips, swap the wiring over to the other relay as a sanity check.

 

Hi,
Nothing wrong with the wiring, only using the one neutral, and as I noted above, one unit works fine whilst the other unit has an issue.
Regs,
Paul

 

The shutter relay does not use the 240V supply for its operation so there is no way it can trip an ELCB. You have a problem in your wiring. Do as Mykel suggests and swap the shutter relays over to prove it.

 

Guys.

New house, a single power feed to the shutter relay, and as I stated previously, I have a second shutter relay that operates correctly. I'm not mixing neutrals or any other dopey configuration. Neutrals are separated out according to the ELCB's etc, etc.


Cheers,
Paul

 

Paul
Have you tested if one of the blinds is low resistance to earth?
Did you also remove the load neutral when you removed the load actives to test?

You say there is only one neutral feeding both the relays so only one active right?
Do what Ashley said.
Swap the relays.

 

Also, you don't say if you are switching the neutrals via the shutter relay. If so, this is really for the European code and not a requirement in Australia. It is possibly, I guess, that internal contamination could provide a leakage path between the active and neutral if you have the neutral connected. It will take you less than 5 minutes to swap the relays over and prove the point.

 

Hi,

I did swap the relays over and one unit had the issue whilst the other tripped the circuit. This was the case with all connections disconnected apart from the active and neutral. Once the neutral was removed the problem went away (which was expected). So, simply having the active and neutral connected caused the issue on one unit and not with the other unit.

As it stands, as the relay unit does not appear to require a 240V input I have this disconnected and just switching the active to the roller blinds.

I'll be looking for another two relay units in the near future so will be interesting to see how they behave.

Apologies if my last reply sounded a little short, back to work after 7 weeks off.


Regs,
Paul

 

Hi Paul
So it is working now?

It sounds like from what you say that there is a short circuit between the active and the neutral inside the relay.
Not an earth leakage fault.
The relay could be tested for this and should be returned if that is the case.

It is usually possible to distinguish earth faults as opposed to overload or short circuits by indicators on the circuit breaker/RCD combo when it has tripped.

I better add that if you are not an electrician I recommend that you do not do this work.

 

Yes, it is working now. I should mention if I hadn't already that when connected with active and neutral, the circuit did not trip immediately. It was only after selecting either the open or close buttons on the unit. So, not likely to be a short between active and neutral.

I am an electrical fitter by trade however not a contractor so can only work on my own house.

Regs,

Paul

 

Hi Paul

It's hard to know not being there but it still sounds to me like a short between active and neutral when the relay is operated.

If the actives and neutral were removed from the load terminals then I cant see where you might get a path to earth.

I think it is worth getting to the bottom of it and that's why I suggested assuming it's a combo to check the indicators on the breaker to confirm what type of fault tripped it.

If you leave the relay connected to CBus.
Powered up with the active input only and removed the load wires.
Then if you are able to measure 240V to earth from either of the unused neutral terminals during switching should prove it.

It's not a feature you should expect from CBus and if it has happened would take quite a toll on the relay contacts.