Public Area lighting problem?

[rons]

I have been asked to look at a lighting problem in an entrance to a small block of apartments. The original install consisted of 28W 2D light fitings, 8 of, driven by a 360 PIR motion and daylight settings.
The 2D lamps were consistently burning out and costing the owner and tenants much frustration and costs. So the 2D fittings were replaced with lower cost fittings with incandescent bayonet lamps. They then experienced MCB trips when a lamp failed. So CFL lamps were fitted which although more stable the lamp failure rate is excessive. Initially I have increased the time period on each PIR to avoid too much switching, with the darker nights the PIRs were switchning quite frequently. I am not convinced this will be a workable solution. Any ideas from the forum?

 

[UNG]

Might be worth using a data logger to check the voltage over a 24 / 48 hour period had a similar problem a few years ago where the voltage increased steadly in the evening (and more so at the weekend) because the local sub station transformer wasn't retapping itself properly and as the local area load decreased, the voltage increased. I only found this by accident as I got a late night call out to a faulty CCTV camera that when checked had a supply voltage of 272V, during the day the voltage returned to 238V, the CCTV system in the previous 6 months had also seen an unexplained increase in the number of lamp replacements required and this coincided with the sub station transformer being changed some months earlier