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Installed a new LED photocell on some parking Lot lights with New Corn Cobb 150 Watt Replacement Bulbs. Breaker trips when Lights turn off. Why?

Location
Newport News, Virginia
Occupation
Master Electrician/Contractor
I installed a new photocell on some Parking Lot lights. When the photocell turns the lights off at Dawn the Breaker will trip also. I think it's a bad breaker. Going Monday to check into situation. Works fine until photocell turns lights of in the morning.
 
Location
NE (9.06 miles @5.9 Degrees from Winged Horses)
Occupation
EC - retired
Why would it be a bad breaker?
Are you sure it trips as the photocell opens, or is that what you've been told?
Do a FOP across the breaker contacts while it's under load. CK amperage.
Does the photocell control the lights directly, lighting contactor or standard contactor?
 
Location
Newport News, Virginia
Occupation
Master Electrician/Contractor
This was the complaint I got. I haven't been out there yet. Was told lights were on at night. Lights were off in the morning and the Breaker was tripped. Customer had to Reset the Breaker in order for the Lights to come back on. No Contactors involved. (5) 20 ft Pole Lights with Corn Cobb LED bulbs.
 

kwired

Electron manager
Location
NE Nebraska
Occupation
EC
This was the complaint I got. I haven't been out there yet. Was told lights were on at night. Lights were off in the morning and the Breaker was tripped. Customer had to Reset the Breaker in order for the Lights to come back on. No Contactors involved. (5) 20 ft Pole Lights with Corn Cobb LED bulbs.
So they don't know when it trips. Might simply be overloaded or there is some intermittent fault and photocell isn't part of the problem.
 

Fred B

Senior Member
Location
Upstate, NY
Occupation
Electrician
Don't rule out a faulty photocell switch. Could be an internal fault that doesn't fully open the circuit. Even though it is a new from box.
 

AC\DC

Senior Member
Location
Florence,Oregon,Lane
Occupation
EC
Well it would seem your answer is solved in how you posed the question. If it’s works all night and has a problem ONLY when switching to off position. It’s the photo eye. Now it could be something else but sure seems like it’s that. Process of elimination. Take an amp reading and then replace the eye.
I have never had an eye do that before but everything cheap nowdays
 

Little Bill

Moderator
Staff member
Location
Tennessee NEC:2017
Occupation
Semi-Retired Electrician
With the OP only getting info from others, the breaker could have tripped on overload during the night. They only said it was tripped in the morning. Unless someone was there when the lights were still on and still there when it was light outside when the PC would being opening, then it's just a guess as to when it tripped.
Still time to check both the breaker and the PC. Also need to make sure the PC is rated for LED.
 

MD Automation

Senior Member
Location
Maryland
Occupation
Engineer
Temporarily connect a clock to the circuit, set it to correct time, and you can see exactly when it trips.
Super genius!!
Not sure I have a mechanical clock lying around anymore, but I love the cheap troubleshooting idea.

Other quick ideas...

Depending on how the PC works and your access to it, you might be able to shade the sensor (or put a bag over it) and get the lights to come on. Then you can test current draw, FOP across breaker (and PC).

And most importantly, then you can remove the shade or bag, the PC should turn the lights off and you can be right there to observe what happens.

Just thinking out loud.


Will also echo the check of the PC rating for LEDs. But, the big problem typically with LEDs is current spike at switch ON. I've been meaning to create a thread on this with some interesting problems I had 2 years ago with switching on some LEDs and the problems it caused on a custom made system we were building. That's not to say bad things could happen at switch OFF.
 

kwired

Electron manager
Location
NE Nebraska
Occupation
EC
This was the complaint I got. I haven't been out there yet. Was told lights were on at night. Lights were off in the morning and the Breaker was tripped. Customer had to Reset the Breaker in order for the Lights to come back on. No Contactors involved. (5) 20 ft Pole Lights with Corn Cobb LED bulbs.
So they don't know when it trips. Might simply be overloaded or there is some intermittent fault and photocell isn't part of the problem.
What I was getting at is photo cell likely not the problem here. Breaker likely tripping because of fault or overload sometime during the night which would still leave lights off in morning with breaker tripped. Need to know when and why breaker is tripping and not assume it trips when photo cell shuts lights off, unless it is proven that is the moment it is tripping.
 

AC\DC

Senior Member
Location
Florence,Oregon,Lane
Occupation
EC
I installed a new photocell on some Parking Lot lights. When the photocell turns the lights off at Dawn the Breaker will trip also. I think it's a bad breaker. Going Monday to check into situation. Works fine until photocell turns lights of in the morning.
Sounds like it was fine till the photo eye was put it?
 
Location
Newport News, Virginia
Occupation
Master Electrician/Contractor
If the breaker is reset during the day, are there any issues when the lights turn on at dusk?
Is it one photocell per lamp fixture? Or does one photocell control a string of lights?
I removed the Old 150 Watt Lamps and installed the Corn cobb bulbs in 4 Pole Lights with 3 heads per Light Pole operated by a photo cell. Worked fine or 4 weeks then the photo cell went bad. Replaced with a photo cell for LED lights. Worked Ok or 1 week. Then I get the call with the complaint from the customer having to turn the Breaker back on at night in order for the lights to come on. 1 photo cell for 4 pole lights.
 

hillbilly1

Senior Member
Location
North Georgia mountains
Occupation
Owner/electrical contractor
I removed the Old 150 Watt Lamps and installed the Corn cobb bulbs in 4 Pole Lights with 3 heads per Light Pole operated by a photo cell. Worked fine or 4 weeks then the photo cell went bad. Replaced with a photo cell for LED lights. Worked Ok or 1 week. Then I get the call with the complaint from the customer having to turn the Breaker back on at night in order for the lights to come on. 1 photo cell for 4 pole lights.
Were the existing 150 watts HId? New LED’s line voltage? Or direct replacement (uses existing ballast)?
 
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