×
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

4 kV Swgr Voltage Spikes

4 kV Swgr Voltage Spikes

4 kV Swgr Voltage Spikes

(OP)
We were trying to capture capacitor switching transients on 4 kV metal-clad switchgear using an Electro Industries Nexus 1500 meter. With the transient voltage trigger set at 175% of nominal, we got a large number of transients before we were able to switch the capacitors. There were so many of these transients that the transient log file filled up in about 10 minutes. There were multiple voltage spikes of very short duration occurring at the peaks of Phase A voltage and sometimes on Phase B. See the attached waveform.

Have any of you experienced such voltage spikes? Any idea what would cause them? The transients do not appear to cause any operational problems. The switchgear serves a 3000 HP motor without a VFD, another 3000 HP motor with a Rockwell PF7000 VFD, and two 4 kV - 480 volt transformers. The 480 volt load includes motors, some with PWM drives and some motors without VFDs. Measurement was made through 2400-120 volt VTs.

Could these spikes be a measurement anomaly? The width of the spikes is such that they may only be one sample wide at 1024 samples per cycle.

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