Heavy Duty Relay Induction Query (not asked before)

Thread Starter


Joined Oct 5, 2009
Hi Everybody,

Thanks for stopping by: I would appreciate your thoughts and help if possible, please.

I have two security lighting ballasts at 1000w each.
They create an enormous induction at start-up.

Would it be appropriate to put in some relay/mains load protection here of the resistor/capacitor/diode kind?
If so, what values should I be using?

Many thanks again for stopping by, any thoughts are appreciated.



Joined Feb 12, 2009
They create an enormous induction at start-up.
That's how they work!

Not only does the inductance control the current in the running lamp but, on start-up, in conjunction with the ignitor, a voltage spike starts the lamp.

Hopefully, you have a power-factor-correction capacitor across the supply?

This not only corrects the P.F. but will also help to prevent voltage spikes being fed back to the supply.