×
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!
  • Students Click Here

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Students Click Here

Jobs

Capacitor Maintenance Procedure

Capacitor Maintenance Procedure

Capacitor Maintenance Procedure

(OP)
I am currently working on a procedure for field inspection and maintenance of medium voltage grounded Y-connected capacitor banks for use on power distribution system (utility). I need some guidance in preparing this procedure especially as it relates to testing the banks for defective units. I am not too clear if the individual units to be tested should be left grounded after they have been de-enrgized and discharged for at least 5 minutes. My problem is that if the phase bushings are grounded (which is normally part of the procedure for de-energizing) then the capacitance meter will record an overload condition because the units will be effectively shorted to ground since the neutral bushings are always grounded.
Please advise accordingly.

RE: Capacitor Maintenance Procedure

gcameron:

For normal maintenance procedures we clean each can, check for any visible defects, and tighten connections.
If necessary we disconnect each can totally and measure its capacitance. Faulty cans are replaced. To balance the total capacitance of each phase (for the three phases) we shift some cans to keep the capacitive difference between the phases as small as possible.  

 

Failure seldom stops us, it is the fear for failure that stops us - Jack Lemmon

Make the best use of Eng-Tips.com
Read the Site Policies at FAQ731-376

RE: Capacitor Maintenance Procedure

A good common sense test for low voltage (480 v) capacitor banks.
1> Whenever you walk past a capacitor bank, drag your hand over the cans. If one is defective, it will be cooler than the others. If so, test further.
2> Check currents with a clamp-on ammeter. This will instantly tell if a capacitor is off spec.
This is more detecting faulty units than maintenance but you may be able to adapt in part to your application.

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members!


Resources