Thanks for all your input,
I think they were 250W metal halides with standard ballasts (non electronic) and fitted with PF correction capacitors.
The AC3 rating is indeed a motor current rating. Someone said there is a rating for lighting contactors and it is designated as AC21 though I have not seen this rating personally.
I am not sure how many lamps are on each circuit only that the total load per circuit is between 13 and 17 Amps
You are right Mike if I were the contractor I would have looked at a larger size contactor before now.
I still find it disturbing that the neutrals on the terminal strips, are getting hot enough to melt the plastic of the strips. I was told that the rating of these strips was matched to the contactor ratings.
Kiwi if you have any links to manufacturers which have data on numbers of light fittings for contactor sizes it would be appreciated.
There shouldn't have been too many operations on the contactors as this all part of new work at an Abattoir boning room which was commissioned only three months ago December last year. I would think there would be only two operations per day, one at the start of the shift the other at the end of the day. This would be far less than the thousands of operations a correctly installed contactor should be capable of.
gideonr, looking at the manufacturers tables, most metal halides seem to draw about 120% of their full load currents between 1 and four minutes.
Paulusgnome, I have read in one cataloger that the contactor must be able to withstand the inrush current for power factor corrected fittings and they that the inrush for these fittings is almost the same as incandescent lighting.
Thanks your help guys.
