Hi all, Can a 30a ac Cbreaker be used to replace a 30a Dc circuit breaker for a dc drive, in the event of an emergency?.. and obviously no dc replacement...
669
c.thanga raj
optimalraj
May 2, 2006 10:37 am
Dear Gomathi In our electrical system (50Hz) have the time period 20 (1/50 seconds) milli seconds for one complete cycle (360 electrical degrees). According to...
670
Senthil kumar
senthilkumar...
May 2, 2006 10:38 am
Hello Mark Empson usually in our village for pumping (Centrifugal pump) for field,some times two phase only available, that time will we will remove fuse of...
671
Senthil kumar
senthilkumar...
May 2, 2006 10:39 am
hai mahesh i think you consider 1.2 times of DC current, for using for AC contactor & should derated the contactor suitable for DC current Regards Senthil ...
672
Senthil kumar
senthilkumar...
May 2, 2006 10:39 am
hai friends if we use single phase supply, we cannot able produce rotational magnetic field , then we required capacitor for that. so please explain detail. ...
673
Mohamed Salim T
sthurakkal
May 2, 2006 1:22 pm
The right method is to convert the motor in to delta connection and drive the motor with the 230 V 1ph/230 V 3 Ph VFD. thanx Mohamedsalim.T Senthil kumar...
674
Mohamed Salim T
sthurakkal
May 2, 2006 1:28 pm
For low and fractional HP motors the motor can continue to run if the the single phasing occurs at small or no load while the motor in motion.This will result...
675
Mohamed Salim T
sthurakkal
May 2, 2006 1:38 pm
if u know the time period between the volatge and current,say T ,the pf=cos(2*180*50*T) where T is in seconds. where 50 is the frequency in Hz. Mohamed salim.T...
676
praba karan
emprabaakar
May 3, 2006 9:28 pm
Hello everybody, Any particular reason for using a low voltage rating motors(350-380V) in elevator application. regards, M. Prabakaran. ... Yahoo! India...
677
manas_r42
May 6, 2006 5:30 am
It will be considered a great help for your guidance on selection of gapped core for the above....
678
rohit upadhyay
rohitrag2
May 6, 2006 7:48 am
Dear all, I have an induction motor of 20 hp driving a centrifugal blower can anyone tell me what is the reason of unequal currents in all three phases. the ...
679
c.thanga raj
optimalraj
May 6, 2006 9:10 pm
Dear Rohit The primary cause for unbalnce current is due to unbalance supply voltage. If 1% voltage unbalance will create 4-5% unbalance in current. In fact,...
680
pawar_np
May 6, 2006 9:10 pm
Dear All, We are using a H.T Motor of 2500 KW rating for running Compressor. The actual load on the motor, however, is only 930 KW. This is only about 37 % of...
681
prasad pawar
pawar_np
May 6, 2006 9:11 pm
dear rohit , there is no any harm for this unbalance current .if there were more than 3% unbalance current then it creates problem.check your i/c 3# voltage...
682
tmempson
May 6, 2006 9:16 pm
Hello Have a look at the efficiency curves of the motor, you may well be surprised. Induction motors, especially large induction motors, operate at high...
683
tmempson
May 6, 2006 9:21 pm
Hello Rohit An imbalance in phase currents is not uncommon and tends to get worse as the load is reduced. There is often an inherent imbalance in the...
684
Mike Burch
mburch46
May 7, 2006 12:25 am
Hi Fella's I am trying to repair this radial arm saw at work that had its wiring all jerked up by a former employee. This motor is a capacitor ...
685
s.ramesh smrames
smramesh_sg
May 7, 2006 7:50 am
dear all , 1. please illustrate to me about the Auto Main Failure panels details with circuit diagrams and function principle. 2.while synchorenising the...
686
Mike Burch
mburch46
May 7, 2006 2:46 pm
Hi Fella's I am trying to repair this radial arm saw at work that had its wiring all jerked up by a former employee. This motor is a capacitor ...
687
Mahesh Govender
MaheshGo@...
May 8, 2006 7:13 am
Hi all, Can a 30a ac Circuit breaker be used to replace a 30a Dc circuit breaker for a dc drive, say in the event of an emergency?.. and obviously no dc...
688
presidium
continentalc...
May 8, 2006 7:14 am
Hi all, I just want to know if anybody can share their toughts on this: 1. We have 460VAC,phase , 40 hp motor, 46.8 A, 3565 rpm, used for high speed puree...
689
Venugopal Balla
venpada
May 8, 2006 9:35 am
Which make and model / type of Soft Starter is installed ? Its always preferred to use a AC Variable Frequency Drive ( VVVF/AFD/VFD) Inverter as installation...
690
tmempson
May 8, 2006 7:40 pm
Hello Mahesh Definitely not unless it is rated to do so. When opening an AC current, there will be an arc that will extinguish at the next zero crossing. Wic a...
691
tmempson
May 8, 2006 7:43 pm
Hello Leo Provided that the soft starter is set up to enable the motor to develop enough acceleration torque during start, there should be virtually no...
692
tmempson
May 8, 2006 7:45 pm
Hello Venugopal I do not agree that VFDs have a better long time reliability than soft starters. The major issues with drives are the life of the power ...
693
Manjula Gajanayake
manjunadeedil
May 8, 2006 7:47 pm
Dear friends, I am Manjula from Sri lanka. I have to operate heavy weight gate and going to install 5 hp( 3.7KW ) Gear motor. Details, 1440 rpm, 4 pole, 3...
694
manas kamal ray chaud...
manas_r42
May 9, 2006 12:58 am
Dear Manjula, If you are having a 440V,3Ph,AC source then why do you require an inverter. Please e-mail your source and application details so that a proper...
695
Venugopal Balla
venpada
May 9, 2006 5:56 am
Thanks Mark. Can you reply me to the query of VFD tripping with InphaseOut on load conditions for GT3000 292F 200kW 380-480V std. Inverter of ASI Robicon. I...
696
kandaswamy gowrishankar
gksha30
May 9, 2006 7:06 pm
Dear sumit, due to the absence of one phase the other two phases draws more current leads over heating on that two phases causes that coils burn. if you...
