RCBO tripping

[albi]

hello every one i have a problem. i have been called out to a commercial kitchen where the 16A b type RCBO keeps tripping when you turn off a 20A DP switch that controls two dimmers which in turn supplies 2 sets of heat lamps
300w x 5 halogen lamps and 250w x 5 inferred ES lamps.
when the inferred lamps are turned off it trips the RCBO but only.

the inferred at present are not on the dimmer as dimmer is not working

I have tried having only the inferred on but trips cable bells out fine so now scratching my head

 

[westward10]

Change the switch one pole maybe breaking before the other, a significant break causing an imbalance.

 

[ipf]

hello every one i have a problem. i have been called out to a commercial kitchen where the 16A b type RCBO keeps tripping when you turn off a 20A DP switch that controls two dimmers which in turn supplies 2 sets of heat lamps
300w x 5 halogen lamps and 250w x 5 inferred ES lamps.
when the inferred lamps are turned off it trips the RCBO but only.

the inferred at present are not on the dimmer as dimmer is not working

I have tried having only the inferred on but trips cable bells out fine so now scratching my head

What are you inferring?
Sounds like it might be a problem with the switch controlling the infrared fittings.

 

[Mike Johnson]

Can't get away with a thing on here.

 

[radiohead]

Have you done any testing of the circuit? (what's belling out?) The first thing I would do is verify insulation resistance is sound before looking at other causes.
[automerge]1584727827[/automerge]

Change the switch one pole maybe breaking before the other, a significant break causing an imbalance.

In theory one pole breaking before the other should not cause an imbalance. An imbalance in the line and neutral current should only be the result of leakage, usually to earth. Two poles breaking at different times will not result in different line and neutral currents.

 

[ipf]

It's an RCBO, can't be sure why it's tripping. Is it necessarily leakage?
Correct testing (and inspection) is required.

 

[westward10]

Have you done any testing of the circuit? (what's belling out?) The first thing I would do is verify insulation resistance is sound before looking at other causes.
[automerge]1584727827[/automerge]

In theory one pole breaking before the other should not cause an imbalance. An imbalance in the line and neutral current should only be the result of leakage, usually to earth. Two poles breaking at different times will not result in different line and neutral currents.

This has occurred several times on here especially with cooker isolators, replace it problem solved.

 

[albi]

(belling out ) is I have carried out all test and all come back fine. changed the switch fuse spur that was fitted to a 20A DP switch
thank for the all the response