Electric large shutter tripping RCD

[george966]

Hi,

So my shutter door today started playing up.

Trips the RCD in house and garage but only when closing shutter. Does not have any problems opening.
So here is the head scratcher... once you reset the RCDs it closes fine..!!

Only thing I’ve done last week is paint the shutter, it’s driving me mad...

Any ideas greatly appreciated...

 

[buzzlightyear]

Why is the a rcd tripping in you house and garage ,you should. not have two rcd in seires

 

[george966]

I did wonder that, only moved in 6 months ago and it’s as it was.

 

[telectrix]

heavy rain got into the door electrics over last few days????? try a hair dryer.

 

[StephenRowley]

Sure your not getting RCD and MCBs confused?

 

[george966]

Don’t think rain has got in as it as it’s a brick building and the shutter is protected.

The MCBs don’t trip just the CU’s RCD’s

Like I say I’ve only painted it which I assume is just a coincidence.

The fact that once you reset the RCD and then it works is baffling me.

 

[Wilko]

Hi George - sorry to hear the door is playing up. Taking the "easy road" when extending power to a garage often results in 2 RCDs in series on the same circuit. This almost always means that both will trip if there's a fault, as they both see it.
Does the garage door opener plug in? Perhaps try it on an extension lead back into the house to eliminate the garage wiring from the mix.

 

[george966]

Hi,
No it’s hard wired it’s a big shutter 4m x 4m
But that’s not a bad idea.

It’s worked fine for last 6 months

 

[Wilko]

Is it an older style one with end stops and switches etc?

 

[george966]

Hi, I would guess it’s 20 year old, but that’s a guess as we have only lived here 6 months, to operate it there is a key switch on the left wall, I’ve checked that dry as a one and working perfectly.

 

[buzzlightyear]

what is with the bold bearing in the corner, are you a weight lifer .

 

[george966]

Yeah in my spare time.

 

[buzzlightyear]

Yeah in my spare time

snap , my weights are a bag of beans dragged from Tesco's.

 

[george966]

 

[Lucien Nunes]

Possibly leakage from one or other motor windings that are at different voltages from earth depending on direction, likewise limit switches if they work at mains voltage.

Tripping once and then operating without tripping is a bit peculiar but not unheard of. Sometimes it just takes a whiff of voltage to drive off a leakage path momentarily. Also, if a DP relay is slightly snappier to pull in the second time, it can avoid a capacitive leakage transient that sometimes causes a spurious trip if the line pole closes fractionally before the neutral.

There are various other possibilities but they are all a bit vague. Would need some proper test results to make headway troubleshooting this. If you find the fault, please let us know as it is an interesting one.