Capacitor Banks

Hello TomHaRa

The interlock circuitry is there for safety reasons.

It may be possible to bypass the interlock arrangement, but without knowing the present system equipment, complete with protection relays and how they are interconnected, it is best to leave it well alone.

The reasons for not interfering are:

1. Damage to equipment
   
2. damage to persons,
   
3. Possible invalidation of any Insurance Policy, if something went wrong.

Best to get the transformer problem sorted out, and get the plant back to normal, as soon as possible.

Kind Regards....

Thanks Sparkstation,

unfortunately we need to run the cap bank since the transformer problem takes time to be sorted out. currently we are in progress in startup our plant and a few HV motor are in place. now the PF is 0.74 lagging and what is the causes if we over energize the cap bank. is it the "lagging" term means that the kVar is in +ve magnitude while "leading" the kVar will be in -ve magnitude. Please correct me if i'm wrong. thus if possible, need your help to guide me to the relevent site for my reading.

Really appreciate for your responds.

If you get a PF of 0.74 with one bank, you should not go leading with two banks on line. In general, it is not good to be leading but it is usually safe up to 0.98.

The main problem you might have if the banks are nearby each others is large current transients when switching. This is because the bank that is already on line will feed the one being switched on. Since capacitors have a very high current sourcing (and absorbing) capacity. The cable impedance will limit the peak current. The peak current is greatly minimized if the banks are equipped with de-tuning reactors.

Before trying it, I would talk to the bank manufacturer and figure out why they had this interlock. The interlock need might still be valid and should not be bypassed. It is better to be safe than sorry.