batteries with switchgear

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jimbo123

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Some switchgear equipment have a battery bank nearby , are these batteries used for control of all trip functions at all times or is there another source of power to sense the faults for the breakers. The swichgear also has a transfer switch for a gen. When is the battery bank in use ?
I know this was posted before but can't locate thepost
 
Thanks augie, i could not locate that tread. On this battery charger the 120 volt recept. is feed from a panel that is supplied from a ups. This setup is about 20yrs old. Batteries are new.
 
Found some interesting information on some of these treads. One was about the battery charger being off. This one is had wired to a circuit from a panel feed from a ups. I don't know if this switchgear has an alarm to warn of low power for the trips. All i can think of doing is disconnecting the dc cable to see if the switchgear has a warning device attached. I won;t do this until i check this with the chief electrician first.
 
jimbo123 said:
Found some interesting information on some of these treads. One was about the battery charger being off. This one is had wired to a circuit from a panel feed from a ups. I don't know if this switchgear has an alarm to warn of low power for the trips. All i can think of doing is disconnecting the dc cable to see if the switchgear has a warning device attached. I won;t do this until i check this with the chief electrician first.
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we have charged these breakers by hand when do they charge automaticlly ?
a fault happened once and the cb never tripped, could this be because the dc is not connected in some way to the trip units?
 
Jimbo123 please give us some more information, like the type of breaker.

Look at the breaker nameplate to find this information.

If there is not any power to run the spring charging motor, then there is probably not any power to trip either. I am making an assumption that the motor & trip circuit share the same source & fuses, which does not have to be the case, they can be seperate.

Typically, the motor would charge the closing springs as soon as the power for the cubical is switched to "on", provided the secondary contacts are engaged. The motor would also charge the closing springs after each "CLOSE" operation.
 
These breakers are ds and dsl breakers. We did a generator test that backs up the switchgear and on return to utility power the main breaker did not close , after a few minutes of not knowing what to do the electrician foreman opened up the door for the main and manually charged the spring, hit the close button and utility power was back , then gen shutdown in a few minutes.
This is why i am concerned if the dc is actually tied to the breakers. Also after the gen test we checked other breakers for the charge condition and found two other breakers that were not charged. Why would these breakers need to be manually charged ? They do have charging motors.
 
Is there a test we can do to confirm that the dc power is connected to the trips for the breakers by using a spare breaker already in switchgear. There has been two different times where the charging springs had to be manually charged for the breakers to close. Once on the main after a gen test, and once on a sub feeder breaker after checking all spring conditions [charged or not]
 
It sounds like you need to call a testing company to come look at the multiple issues you have, hard to troubleshoot this for you on a fourum. Look in the metering cell, you should have fuses for your control power.
 
thank you , zog. just trying to pick the brains of the smart people to get as much infomation as i can so i can someday pass it on down.
 
Jimbo123, DS breakers may not have a charging motor. Does the breaker nameplate list a charging motor & operating voltage? They can be manual.

If the trip unit is an Amtector then it does not require a DC source to operate. They operate using the CT current. The CTs are built onto the breaker. They are red if I remember correctly. It could be the trip setting was too high.

Here where I work we have DS, and many years ago 30 feet of new LV bus duct dissappeared in a shower of sparks because the Amtector did not have any ground fault protection & the phase trip setting - long delay took it's sweet time.

I agree with ZOG that you need a testing company because your gear has seen too many winters.
 
sg-1, interesting story about the ds breaker and the bus duc.

The breakers do have cts installed in them, i remember speaking to a contractor and that was brought up at that time of a repair. They did at one time have amptectors now they have digatrip 500 installed on them . As far as charging motors installed , that will have to be looked into to confirm that.

Thank you for all you timely responses and great information on this switchgear . If we had the option of bringing in testing people for this we would but like alot of companies they wait until it's too late before anything gets done. We have alot of questions to get answered.

Again thanks alot you guys are a great source of knowledge.
 
Just look at your nameplate, if it has control voltages listed for charge and close it is electrically operated, if not it is manually operated.
 
SG-1 said:
Here where I work we have DS, and many years ago 30 feet of new LV bus duct dissappeared in a shower of sparks because the Amtector did not have any ground fault protection & the phase trip setting - long delay took it's sweet time.
.
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You mean the ampetector actually worked? :)
 
jimbo123 said:
Is there a test we can do to confirm that the dc power is connected to the trips for the breakers by using a spare breaker already in switchgear. There has been two different times where the charging springs had to be manually charged for the breakers to close. Once on the main after a gen test, and once on a sub feeder breaker after checking all spring conditions [charged or not]
Click to expand...

There are many possible issues here, they are not EO, you have a control power issue, the breakers are not wired right (Hundreds of different wiring configurations possible and if this breaker was swapped out at some point they may not be the same), bad charging motor, bad aux switch, charging mech issues, etc.......

At the bottom of your nameplate there should be a series of wiring codes (2B, 3A, 5C, 14D, 11A, etc...) that is a big clue.
 
zog said:
You mean the ampetector actually worked? :)
Click to expand...

Shocking, but true, it did trip in it's own sweet time. :D

The Christmas before I had tested all the ampetectors during a shutdown & exercised the breakers. I reported to the maintence supervisor, that particular breaker did not have any ground fault protection. A few months later a tool left inside some busduct during assembly finally fell into position. A maintance guy ran to the gear, had opened the door, & was reaching for the "push to open" button & the breaker tripped with his thumb just inches away. :eek:hmy:

Another maintence man was up on a lift with the busduct burning toward him. :eek: His partner was on the ground controlling the lift, but was hypnotized by the giant 4th of July sparkler above. :jawdrop: He was nearly clobbered with a wrench. :slaphead:

About 20 or 30 women were working below the duct. One was a bad motorcycle mama. She fell making the turn as they were heading out. She was laying sideways in the aisle still trying to run. She finally passed out, was placed on a streacher and taken to the plant nurse. :bye: Nobody was afraid of her after that.

Of course, all the testers went to watch it burn. :cool:
 
I spoke to the manager and lead electrician to get someone in here to look at the gear. Trying to get it across that we might have a problem . Something doesn't seem right to me, There is 4 breakers in 1 verticle compartment all 4 breakers springs read "discharged " found atleast 8 reading discharged. 1 of these " main cb " was just manually charged when found " discharged " during a gen test.

It appears there are more then one control voltage for the gear, 48vdc for shunt trip and 120ac for motor.

Getting the company to stop or shut down is a big chore . I just hope they find something wrong { minor } to justify this. My lead does not know much about the switchgear either , the company always relied on the contractors for there help.
Will let you guys know of their findings after the contractors report . Thanks again.
 
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