Capacitor Bank Testing Question
Capacitor Bank Testing Question
(OP)
Hello,
We are receiving a new substation at a wind farm equipped with capacitor banks. At a previous job, they used Joslyn zero voltage switches to engage the cap banks and during final testing a digital O-scope was used to confirm the timing was correct. 2 of the 6 switches had to be recalibrated as a result of this testing as there were significant voltage spikes.
I am at a new site now and they are using a different method. They have Southern States pre-insertion closing resistor switches which use a resistor as a shunt to limit spikes. I am new to this type device, and they are telling me there is no need to capture closing waveforms as this is a very simple design unlike the zero-voltage switches from Joslyn.
Question: Am I being fed a line? Seems to me you'd still need to verify the resistor is engaging prior to the switch closing and providing a smooth transition. Any thoughts are greatly appreciated.
FEinTX
We are receiving a new substation at a wind farm equipped with capacitor banks. At a previous job, they used Joslyn zero voltage switches to engage the cap banks and during final testing a digital O-scope was used to confirm the timing was correct. 2 of the 6 switches had to be recalibrated as a result of this testing as there were significant voltage spikes.
I am at a new site now and they are using a different method. They have Southern States pre-insertion closing resistor switches which use a resistor as a shunt to limit spikes. I am new to this type device, and they are telling me there is no need to capture closing waveforms as this is a very simple design unlike the zero-voltage switches from Joslyn.
Question: Am I being fed a line? Seems to me you'd still need to verify the resistor is engaging prior to the switch closing and providing a smooth transition. Any thoughts are greatly appreciated.
FEinTX






RE: Capacitor Bank Testing Question
With the Southern States switch, it would operate much the same way. I'd be tempted to try it on an energizing operation of the cap bank and see if it anything bad happens. It shouldn't, but it is a mechanical device.
RE: Capacitor Bank Testing Question
I saw at least one JOSLYN VBU synchronized with a system of lights. One light was connected across each vacuum bottle and they had to turn on/off at the same time (a small tolerance was allowed while moving the closing mechanism). It would have been nice to see the waveform. However, they seemed to close well. It was tripping the bank that caused the VBU its problems.
RE: Capacitor Bank Testing Question
RE: Capacitor Bank Testing Question