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I have a question about a strange situation.
Customer has a utility street light (old Mercury-Vapor) on his corner outside his house. Within the last two months, he has noticed at night that this light will cycle off & restart every time the 110 volt motor on his oil-burner furnace starts up.
Which makes completely no sense at all. His furnace blower motor draws 35 amps on start-up, runs at 7 amps. Fed with a piece of 14-2 Romex with ground, back to the 200 amp service entrance breaker box.
The street light is fed from the overhead utility power that shares a xfmr with the customer's house. But, this light is in a string of four lights, none of the other lights are affected by this furnace motor.
Finally, the customer is noting radio interference at night in the home. I am assuming that it has to be the faulty street light.
This is not a crisis, but I would like to get it resolved. Have any of you ever seen a situation like this before?
Rick
 

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I have a question about a strange situation.
Customer has a utility street light (old Mercury-Vapor) on his corner outside his house. Within the last two months, he has noticed at night that this light will cycle off & restart every time the 110 volt motor on his oil-burner furnace starts up.
Which makes completely no sense at all. His furnace blower motor draws 35 amps on start-up, runs at 7 amps. Fed with a piece of 14-2 Romex with ground, back to the 200 amp service entrance breaker box.
The street light is fed from the overhead utility power that shares a xfmr with the customer's house. But, this light is in a string of four lights, none of the other lights are affected by this furnace motor.
Finally, the customer is noting radio interference at night in the home. I am assuming that it has to be the faulty street light.
This is not a crisis, but I would like to get it resolved. Have any of you ever seen a situation like this before?
Rick

The lamp is old and the start of the motor is dropping the voltage just enough to kill the arc in the lamp,also that lamp is drawing a little more current because of the age of it those lamps have a very long lifespan and I'll bet it's not giving out as much light as it should,that ballast is working harder to keep that lamp lit and I'll bet that that's why it's creating radio interference.
 

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That head should have been changed to a HPS back in the 80's.
 

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The HPS street light in front of my house has been cycling for the past 6 months and every time it tries to ignite, it causes a lot of static on the radio due to the ignitor firing. MV does not require an ignitor but the startup can cause radio interference.
 

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The lamp is old and the start of the motor is dropping the voltage just enough to kill the arc in the lamp,also that lamp is drawing a little more current because of the age of it those lamps have a very long lifespan and I'll bet it's not giving out as much light as it should,that ballast is working harder to keep that lamp lit and I'll bet that that's why it's creating radio interference.
The HPS street light in front of my house has been cycling for the past 6 months and every time it tries to ignite, it causes a lot of static on the radio due to the ignitor firing. MV does not require an ignitor but the startup can cause radio interference.
Good post Guys, I never would've known that. Crazy.
 
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