Interested to Buy Any Domain ? << Click Here >> for more details...
why contactor not provided between output of VFD and motor?
- 6 Answers
- 21553 Views
- Siemens, I also Faced
- E-Mail Answers
Answer Posted / revansiddappa p.h.
Basically contactor is used to make and break the circuit
like any switch. For handling higher current and volatge we
use contactor; not only for motors.
Between VFD and motor; contactor is not required.
Because VFD will have features like enable and disable.
VFD will use IGBT's inside for switching application.
As IGBT's are semiconductor ; switching is fast compared
to electromachanical type contactor.And IGBT's handles
larger currnts.By enabling or desabling of VFD we can
Start/stop motor(with speed command). If contactor is used
there will be some time difference in swithcing ON/OFF of
IGBT and contactor which may lead to failure of IGBT and
motor winding and insulation. So it is meaning less to use
conatctor and also cost will be more.
| Is This Answer Correct ? | 23 Yes | 4 No |
Post New Answer View All Answers
On 400 amp factory load how kvarh capacitors provide
Dear All, I am new in construction company , my boss ask a question at time of interview , If we have 60MW generation and Single Power Transformer step-up we have. if CMR 50/60MVA , ONAN, ONAF respectively , is it sufficient or not ? for that much power to transfer,
A 3-PHASE TRANSFORMER IS USED TO STEP-DOWN THE VOLTAGE OF A 3-PHASE, 11KV FEEDER LINE. PER-PHASE TURNS RATIO IS 12.FOR A PRIMARY LINE CURRENT OF 20A, CALCULATE THE SECOUNDRY LINE VOLTAGE, LINE CURRENT AND OUTPUT KVA FOR FOLLOWING.A)STAR- DELTA.B)DELTA-DELTA.
i have gear oil pump with single phase motor.some time its motor starts running in reverse direction rather than forward direction...whats the reason behind this issue. 1- either capacitor is week? 2- or winding is week?
What is the difference between diode and a transistor in terms of the direction of current flow?
what is the difference between ups & inverter
Define phase cross over?
send me any model test paper of clerical post of state bank of india.......
i've iocl interview.. if you know the interview process please give me information..
The ripple frequency in output of fullwave bridge rectifier is a. Half the input b. Twice the input c. Same as input
Any one can explaination about calibration with rotating sub standards?
what is meaning of sympathetic tripping with respect to relays and give the values for current carrying capacities for copper and aluminium cables from 16sq mm to 500sq mm
what are carbondioxide and dcp used in fire extinguishers
how to find the capacitance value of the motor while running??
please write motor, transformer, Generator setting, fault level calculation of Tr.etc
