Surge protection on site wiring

[Jps1006]

My customer has 8 buildings (townhome buildings) on a 7 acre lot. All of the building lights are controlled by one mechanical timer that has a 120-volt control circuit that pulls a contactor in each of the 28 units to turn on their respective coach lights. This has been working flawlessly for 20+ years. They want to change the timer out to an astro timer, I have a electronic honeywell wall timer in mind. I'm concerned with the potential to fry electronics connected to all that underground copper between buildings. I know the fire panel struggled with false alarms for years during storms because of the copper between buildings.

Is anyone aware of a surge protection device that would be appropriate for this? I'm picturing something that somehow isolates the load wires from everything else. My supplier isn't much help and it's getting more difficult to find expertise. Any ideas or even suggested direction?
Thanks

 

[LarryFine]

How about having your timer control a "master" contactor to control all of the others?

That way, your timer would see no more load than a single contactor inches or feet away.

 

[Jps1006]

I thought about that, but the timer would still be fed from the same 120-volt circuit that goes through the contactor, so a voltage spike induced from a vicinity strike would still see its way back through the contactor (if its closed) and into the line side of the timer. After talking to the original installer, we may just stick with the T101 mechanical clock and a photocell. I imagine those components will hold up better to harsh conditions. I also realized these components are in an unheated exterior J-box, so electronic controls aren't a good option anyway because of the heat and cold.

 

[tom baker]

I don’t care for the Astro timers. I have used a PE to turn on at dusk and time clock to turn off. Or get some low wattage LED lamps and use with PE