Any ideas, on this one..

[Toneyz]

What lamp is in these bollards

Are they all LED's - could it be start up current?

The OP is saying de-energising.

 

[Toneyz]

What lamps are in these fittings?
What type of rcbo is it B,C.
Have you tried disconnecting the photocell and switching through a standard switch?

 

[buzzlightyear]

What lamps are in these fittings?
What type of rcbo is it B,C.
Have you tried disconnecting the photocell and switching through a standard switch?

we will have to wait for the post mortem
I'm afraid.

 

[Octopus]

What lamp is in these bollards

The OP is saying de-energising.

But he does say as soon as any load is added. ....

 

[Pete999]

Clamp the circuit to see what the current draw is.

 

[static zap]

( Daft thought do check contactor is
switching Live , not the other one !)
....Heat steams things up then ....

 

[Pete999]

( Daft thought do check contactor is
switching Live , not the other one !)
....Heat steams things up then ....

good point static

 

[westward10]

I would like to know If the rcbo is actually required.

 

[static zap]

I would like to know If the rcbo is actually required.

No Ants were harmed by this install !

 

[nathz29]

It's a type b rcbo, more good ideas, many heads better than one on this one.

Staring at a cct in the cold today was probably not a good idea, the street lamp heads on due to swap tomorrow might be getting kicked into touch at this rate too!

 

[westward10]

I would still like to know if the rcbo is required.

 

[Deleted member 26818]

I would still like to know if the rcbo is required.

Not according to BS7671.
However it is a requirement of BS7671, not to leave the installation less safe.

 

[Toneyz]

OP can you confirm the tripping of rcbo is it when the lights are switched on please.

 

[nathz29]

Only when switching off and only when, bollard (s) to the rear of the property are in cct.

 

[westward10]

Not according to BS7671.
However it is a requirement of BS7671, not to leave the installation less safe.

Why would it be less safe if an alternative device provides fault protection. If it is a TN system and installation methods permit an rcd may not be required for additional protection and would be compliant with BS7671.

 

[Deleted member 26818]

Why would it be less safe if an alternative device provides fault protection. If it is a TN system and installation methods permit an rcd may not be required for additional protection and would be compliant with BS7671.

It’s not a matter of compliance, it’s a matter of safety.
Is a circuit more safe because it has RCD protection, no safer or less safe?

 

[Des 56]

Maybe the contactor is disconnecting the live and neutral slightly out of sink,one is opening before the other causing a momentary imbalance that the Rcbo sees as a earth fault

 

[westward10]

It’s not a matter of compliance, it’s a matter of safety.
Is a circuit more safe because it has RCD protection, no safer or less safe?

If a non rcd protective device provides overcurrent and fault protection without the need for additional rcd protection it is fully compliant.

 

[Deleted member 26818]

If a non rcd protective device provides overcurrent and fault protection without the need for additional rcd protection it is fully compliant.

Again it’s not about compliance.

 

[westward10]

Again it’s not about compliance.

If you say so.