1.Separate the controller power switch, then separate the main switch of the device, before doing the next step it is safer to wait for 20 minutes, note that generally there are discharge resistors inside the capacitors.

    2.  Replace the capacitors with substitudes having the same voltage level and capacity, it is better to have a person to monitor during the replacement since electricity is flowing through the main switch.

    3.If the substituted capacitors have greater capacity, both shunt switches and big line should be replaced with those with greater capacity.

   4.After the replacement of capacitors, test whether the screw is secured, use megohmmeter and multimeter to test the insulation and to find whether there is a short circuit problem.

     For general loads, regardless of calculation, it is common to select the compensation capacitor which capacity is equal to 30% of that of a transformer. For a 630 KVA transformer, the amount of capacity to be compensated should be: 630*30%=189 Kvar. If the capacity of a capacitor is given by 16 Kvar, it is enough to select 12 capacitors, where the total capacity to be compensated can reach 192 Kvar to meet the compensation requirements.

     If the natural power factor of the load is relatively low, it is capable to select a compensation capacitor whose capacity is equal to 40% of that of the transformer; for a 630 KVA transformer, the amount of capacity to be compensated should be: 630*40%=252 Kvar. If the capacity of a capacitor is given by 16 Kvar, it is enough to select 16 capacitors, where the total capacity to be compensated can reach 256 Kvar to meet the compensation requirements.

   Device with functions of low-voltage reactive power compensation and harmonic elimination mainly refers to the configuration of a harmonic reactor on the basis of a pure capacitor compensation cabinet, capable of effectively avoiding capacitor resonance and shunting subharmonic current whose characteristics within 20%-30%.

   Generally, electrical installation company configures a low-voltage capacitor cabinet with a switch cabinet in accordance with the transformer capacity, only used for reactive power compensation. While the pure capacitor compensation cabinet disposed of harmonic problems is not configured with a harmonic reactor.

http://www.ks-gz.com/faq/4.html

    Device with functions of low-voltage reactive power compensation and harmonic elimination mainly refers to the configuration of a harmonic reactor on the basis of a pure capacitor compensation cabinet, capable of effectively avoiding capacitor resonance and shunting subharmonic current whose characteristics within 20%-30%.
   Generally, electrical installation company configures a low-voltage capacitor cabinet with a switch cabinet in accordance with the transformer capacity, only used for reactive power compensation. While the pure capacitor compensation cabinet disposed of harmonic problems is not configured with a harmonic reactor.