Changing the direction of an outbuilding cable

[adam_stubbs]

The only practical way other than running an additional power cable would be M&E interlocks.

Essentially this is the mechanical shared key you suggest with additional signal exchange, you would not be able to energise the generator to the supply if the mains supply is energised. This still requires cables, but is just signal rather than power.

Mechanical alone is generally not acceptable these days, especially by untrained persons.

These keys are not copied easily however as long as you get a proper solution from castell or whoever.

A reverse power relay wouldn't be suitable, if there is any possibility of parallel operation with the supply then you have all the requirements of g59 to content with (rocof or dv/dt etc).

Thanks Julie,

Yes I looked at the revers power protection, and they didn't look suitable they seem mainly for the purpose of protecting generator sets themselves.

That's interesting that mechanical alone would potentially not be sufficient. Its quite a niche situation in question here, but are there some similar rules/regs that you are referring to?

I think if there was a need for a signal cable then probably he might as well have a new power supply cable, which would end up cheaper than the key-switch gear + the electronic actuator

Thanks again, at least there isn't some simple solution I hadn't thought of, this is one of those cases where there isn't a cunning solution to the problem!

 

[Julie.]

I haven't anything specific, but in recent years everything I came across would require M&E rather than just electrical or mechanical.

Castell have quite a selection of stuff, I would imagine they are likely to have something that can retrofit most industrial isolators.