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Reply from Hawker Siddeley technical " I have checked with our records department and they have confirmed that the records for the VSI equipment was not retained, we’re sorry that we could not be of assistance in this instance but maybe we could assist you in the future. Regards Global...

Thanks Marmite. I managed to get a hold of someone in the technical division and am waiting for a reply.

Thank you Marmite for the answer. I have tried to call HS on numerous occasions and have trouble getting through to the correct person in technical. The breakers are Vacuum and are fairly new (installed 2003). The files you attached dont appear to open correctly. Can you please put them up...

I currently have a spare Hawker Siddley VS1 VCB on my site and would like to switch a 11kV 8000kVAr capacitor bank. Does anyone have any experience with these breakers and whether they are rated for capacitor switching? If possible does someone have a brochure and manual for the breakers. My...

Correct me if I am wrong, but when we design individual motor compensation, you cannot just look at the PF of the motor. We look at the no load(Magnetising) current and size the capacitors to about 85% of this value. If you start just adding caps to the motors, you risk self-synchronization and...

kVAr out = kVARrated/((kv1/kv2)^2) = 3600/((13.2/4.16)^2) = 357kVAR

We have a customer who has just installed a 1100kVAR 6.6kV switched capacitor bank on his system. There are 2 incomers. The one incomers has 2 x banks operating correctly but when the new bank switches in during high loading conditions it trips the earth leakage in the substation 220V DB. It is...

Magoo2, bypassing the reactor will result in you not knowing where the tuning point will be. With all the unknowns, it is not advisable until a the system is checked with an accurate model.

Thanks All... rcwilson, I didn't think that there would be a problem with breaker opening but you are correct, the cap will discharge through the windings. jghrist, thanks your graph is going to help me develop a Etap model to fully test the system before we advise the client. I have a...

The reactor is specifically designed with a certain kVAR to tune at a point away from any harmonics (De-tune). If you change the kVAr without changing the reactor you might end up tuning on one of the significant harmonics and amplifying it.

Hi The capacitor bank is on the primary of the transformer. Have being trying to model with Etap and LT spice but done have enough info regarding the inrush harmonics to transformers

I have a customer asking us to directly connect a 11kV 5MVAR capacitor bank with filter reactor tuned to 4.8pu to a 20MVA transformer breaker. The transformer is feeding a submerged arc furnace. The capacitor bank will therefore energize at the same time as the transformer. They don't want to...

Is an active system such as a SVC not better suited to the voltage control problem. Some people I have worked with have suggested resistively grounding the capacitors to discharge quicker. This is practical in LV applications but due to cost of switching devices we found that in MV...

Thanks All I was on site yesterday trying all suggestions. It turns out the temp supply we were using was a ungrounded UPS supply. We connected to a VT supply and the problem was sorted. There appeared to be common mode voltage fluctuations due to differing voltage sources. For once an easy...

Hi All I currentely have a CPU226 with a EM231 (6ES72310HC220XA0). We are using channel A and B for a 4-20mA Var transducer input. We have a HMI connected to the CPU and this is displaying the scaled VAR value. We are having an issue when the 4-20mA signal is sent to the card, we are having...

HI Bozzah I have attached quite a handy tech note from Copper development regarding tuning of capacitor banks. Let me know if it helps..http://files.engineering.com/getfile.aspx?folder=f33f10b0-e1e9-480b-b039-71146956c37a&file=Passive_filters.pdf

HI Stevenal I have a good feeling that the sequence is 123, but I will confirm with wiring. Hopefully swopping the inputs you state will sort the problem. I have a feeling that the red, white, and blue wires are not actually the red, white and blue voltages. I will need to trace the wiring. K

Phovnanian - When the enermax is reading negative, the convention in RSA is that it is leading. The Hioki readings agree with the Scada and the electricity account. I agree with dpc, I feel there are multiple problems that have crept in (Voltage swopped and reversed currents). When I am on...

Thanks for all the help. ScottyUK, drawing the vector diagram as you suggested I can see your point. I am going back to site on monday with a shutdown arranged so I can double check the wiring in the panel. I have a feeling they have crossed the CT wires somewhere. We have already tried...

Hi I have a very strange situation on a cement plant. We have a utility grade billing meter(Enermax)installed. This meter is telling us that the PF is leading at all times. This does not tie up with their electricity account. We where called in to check with a Power Quality analyzer (Hioki)...