Hello to all. On site we have a 6.3kV motor with Drive end bearing D625-6322-C3. On this bearing we experience temperatures to 61 oC. Is this normal wroking temperature? The protection relay of the motor trips at 70 oC. I think this is a little bit more sensitve than usuall. In other...
Hello to all. On site we have a 6.3kV motor with Drive end bearing D625-6322-C3. On this bearing we experience temperatures to 61 oC. Is this normal wroking temperature? The protection relay of the motor trips at 70 oC. I think this is a little bit more sensitve than usuall. In other...
On site we have two cast resin transformers 2MVA running at loads between 50-60% of nominal rating. The air temperature during summer period exceeds the value of 40 oC and sometimes reached 45 oC. The transformers are cooled with natural circulation of air from air holes on the bottom and air...
On site we have a Gas Turbine GE 9FA DLNII. The exhasut frame of thegas turbine is cooled with inlet of air via the TK fans, exhasut frame blowers TK-1 and TK-2. What we have seens until now is the motors working to nominal current, the diverter flap stucking in the middle position. These fans...
Dear all
On site we have one Ge generator 325MVA 4-pole hydrogen cooled with static excitation system EX2100. One of the features of the excitation system is the Power System Stabilizer. Unfortunately this is not tuned yet. Is it possible to tell me some more theoretical or practical data fro...
Dear all. I want to place my question about the installation of arching rings on 400kV overhead lines. These rings are supposed to carry any transient overvoltage and try to break the air gap so they should be placed in the lower length between the live terminal and the earth. Can you give some...
Dear all. On site we ahve a GT generator that is started by means of a static starter (LCI load commutated inverter). At this moment the neutral (star point of generator) is isolated from ground by a disconnector. When GT reaches full speed no load (FSNL) then the neutral disconnector closes and...
Dear all. On site we have a 400kV circuit breaker that connects our step-Up transformer high voltage to the grid substation.
The poles of the circuit breaker have in parallel connection capacitors.
Can you explain why these capacitors are installed?
I guess they are used for precharging of the...
Dear all. On iste we have a three winding step-up transformer connceted to the grid of 400kV via a disconnector and a circuit breaker. The disconnector is between Step-Up transformer and circuit breaker. When we de-energize from the 400kV grid we are instructed to open first the circuit breaker...
Hello to all. I want to ask if you can suggest a vendor with portable earthing devices for 400kV substations. Take in mind that our plant is located in Greece. Here i find it very difficult to locate one.
Dear all, on site we have a 170MVA generator with 15kV voltage output, Y connection, earthed through transformer and resistor.
On this generator we notice from the first day of operation a consistent difference on the terminal voltage, meaning that on normal operation we measure phase A 14.99kV...
Hello to all. On site we have a demin plant. A part of this plant is the mixed bed filters. We noticed , after 1 year of operation that during the step of conductivity rinse the value of conductivity takes a lot to decrease. As a result the sequence stops and you have to manual reset . The...
Good evening to all. On site we have a Gas Turbine GE 9FA DLNII. SOme time before we noticed a sudden loss of flame to one of the 4 flame detectors, after one minute we hde high exhasut spread temperatures and consequent trip of the turbine. When we put back the unit it seemed OK. Can you...
Dear all. On site we have one 6.3 kV motr, 1090kW. This motor is vertical mounted, drivinf one main cooling water pump of our power station. The pump had a very big failure on the bearings and the motor was left running for 20 minutes with currents higher than nominal. the motor has SIPROTEC...
Dear all. On site we experience a fault with VT and CT failed on the generator. These VT and CT are used for excitation control, their secondaries feed the GE EX2100 exciter panel for 9FA generator. I was wondering if
1) for the VT application , i can use the secondary of another VT e.g the one...
Hello. On site i have one generator terminal enclosure with Voltage transformers on the line side of the generator. The primary of these VT's are connected to the busbars by special cables (the cables have red insulation outer sheath and aluminuim wires inside). Apart from that i dont have any...
Hi to all. i want to ask about the level measurement of dark colered oils and chemical solutions as NaOH, H2SO4, HNO3 and HCOOH. Reading form documentation and from some personal experience i would choose the radar level measurement. What i am trying to find is what are the reasons and the...
Hello to all.
I want to ask if there is online or if someone has in pdf files any documentation for the old series of TECMAG flow transmitters from Endress&Hauser. I have tried several times from yahoo but with no result. Can anyone help ? Thank you in advance for your time.
