Check for

Open covers to see that-

No live part is accidentally touching the body. There is no leakage/loss of oil apparent on visual inspection.

These capacitors are single terminal capacitors, with second terminal connected to the body. An internal discharge resistance is permanently connected between the live parts and the body. Thus the meggered insulation resistance will show the resistance of the discharge resistors and not the insulation resistance of the insulation between the live parts of the capacitor and body. Therefore, this value will be different from a minimum of 50 Mega Ohms as required under the Indian Electricity Act.

If the equipment has to be stored for a while, please ensure the following:

Since these capacitors are protective devices, no external fuses are to be used alongwith these.

These capacitors are permanently connected across main buses. There is neither a controlling switch nor a protective fuse to be used for these capacitors.

Quite often a combination of Lightning Arrestors and Surge Protection Capacitors works very effectively. The voltage & kilojoules rating of the lightning Arrestors should be as per Consultant's advice.

All the HT installations, in general, require prior approval by the electrical inspector for compliance with the provisions of the Indian Electricity Act.

We supply these capacitors for a combined Indoor / outdoor applications upto 12KV. The construction for capacitors above 12KV and upto 56KV is mainly of the outdoor type.

When the capacitors are installed within a busbar chamber, adequate safety clearances must be kept between the live parts and the body as well as between the live parts. There should be no sharp points or wire ends standing out. We recommend a minimum distance of 150mm for all capacitors rated upto 12KV.

Height of live parts above the ground should comply with the requirements of the Indian Electricity Act. We recommend a minimum height of 3 (three) metres and above. A double wire earthing has to be run individually on these capacitors. This earthing must have a minimum cross-section of 50X6 mm2 of G.I. strip. It should be securely tied on general earthing system. In case a Lightning Arrestor is also used alongwith capacitors, the combination should have an independent earthing system very close to it. It may be noted that both the surge capacitors and lightning Arrestors are expected to ground the heavy surge currents of small duration without dangerously increasing the potential on their earthing system.

Before commissioning the bank, measure the current output of each unit across 400 volts and keeps a record of current & voltage.

One can calculate the capacitance of the capacitor by the following formula:

If the capacitance is more than 10% of the declared value, please, remove this capacitor from service and advise us.

Quite often, the protective relay on the bus-duct requires that these capacitors must be accurately matched between all the three phases. This requirement must be brought to our notice while ordering for capacitors.

Take a long wooden pole and touch the capacitor body with one end. Hear at the other end for any hum or crackling noises. These could come from within a unit or from outside the unit also. Investigate and eliminate.

Once the bank is energised and switched off, wait for full five minutes. Then earth the bus-system across which you expect to work and keep this earthing while work is being carried on. A standard earthing pole approved by Electrical inspector and with an open trailing copper flexible, which is earthed at one end & tied to the metal probe of the earthing rod, may be used.

Earthing within less than five minutes of switching off can cause damage to capacitors.

If a capacitor system is momentarily earthed and the earthing rod is removed, it can get recharged to a dangerous voltage and can cause accidents. It is best to keep this earthing rod permanently on the bus or live part where work is being carried out. Also remember to remove this when the work is over and the capacitors are to be re-energised.

Check for leakage/seepage of oil on any equipment. This cannot be tolerated. Repair immediately as per details outlined later.

Keep a weekly record of temperature rise for the first six months. If any unit develops more than 200C temperature rise investigate & eliminate the trouble. Failing this, replace the unit.

If any capacitor is found bulging, disconnect it and short it through suitable resistance. Don't try to open the container as dangerous pressure may get developed inside the container. Keep it in open space and shoot it by rifle from safe distance depending on the energy of capacitor.

If the capacitor is leaky, cleanup the leaky spot and solder it with the help of a tin-maker, if the leak is in the metal portion of a welded joining.

If the leak is on the joint between the porcelain and the body-Heat up the capacitor under the sun or in a warm cabinet upto 50⁰C/60⁰C Desolder and remove the sealing washer on top.

Allow to cool and clean the surface with trichlotoethylene. While the surface is cooling, apply properly mixed `Araldite' Or `Dobecote'. This will be slightly sucked in. Allow the Araldite to set for 24 hours. Solder back the sealing washer on top after topping up proper oil - if too much oil has leaked out. Again heat up the unit to 50⁰C/60⁰C.There should be no leakage. The unit can be put back into circuit.