Generator power toasting ballasts

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randall dylan

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Back up generator power is toasting ballasts on some, not all, branch 277v. night light circuits. Under normal purchase power, all these circuits operated ok. This problem only occurs when the gen set is cycled on. No back fed circuits have been found at panels with these trouble circuits. The problem seems to occur when purchase power comes back on line. Could both power sources on at the same time be it ?, why only some and not all circuits toasting ballasts ? Any thoughts ?
 
if it were me first thing I would check is the normal amperage on the emergency ckts, then ampprobe it while cycling the power.
 
randall dylan said:
Back up generator power is toasting ballasts on some, not all, branch 277v. night light circuits. Under normal purchase power, all these circuits operated ok. This problem only occurs when the gen set is cycled on. No back fed circuits have been found at panels with these trouble circuits. The problem seems to occur when purchase power comes back on line. Could both power sources on at the same time be it ?, why only some and not all circuits toasting ballasts ? Any thoughts ?
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Welcome Randall,

Both power sources can't be on at the same time due to transfer switch.

How are you sure that the transfer back to POCO (power company) is frying the ballasts? Is it an instantaneous event?
 
3 pole or 4 pole ATS.


If a four pole there may be a neutral issue at the generator.


Just for starters
 
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brian john said:
3 pole or 4 pole ATS.


I a four pole there may be a neutral issue at the generator.


Just for starters
Click to expand...

Need more info from OP. Strange its only night lite circuit. You post would indicate more far reaching problems. (yet to be discovered?)
 
randall dylan said:
Back up generator power is toasting ballasts on some, not all, branch 277v. night light circuits.
Click to expand...

Is the voltage dropping during switching or generator use?

The American Electricians' Handbook 14th ed. pp 7.275 recommends "close differential-voltage supervision" for starter-type fluorescent lighting. Apparently, it is extremely voltage-sensitive, and below 90 percent voltage it becomes uncertain as to whether or not a fluorescent lamp will light.

If your sure the night-light ballasts are getting damaged, you might want to log the line voltages & frequencies for transient surges during the switch overs.
 
Randall,

Can you provide more information on the transfer switch? Chris is correct that the utility and generator sources can't tie together with an "open-transition" transfer switch (the most common type). However, if the system uses "closed-transition" switching, then the two sources are briefly tied together.

I'm curious, are the night/emergency fixture ballasts the same brand and model as those that aren't failing?
 
generator

generator

test the generator for voltage current and hz , most standby generators have adjustments if these are'nt rite. Read the owners manual should have a flow troublshooting chart..
 
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