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  1. laundry

    Megger Test

    Hi The megger should be set to 10k and the reading to earth should be 0.ie no leakage.If you are testing between windings then you should have equal readings between windings.Iam not sure that you should be doing this test as you do not sound competent to do this,as the motor is a HV class...
  2. laundry

    Electrical drawing help

    Hi Why dont you just aske your electrician to explain how to read a drawing and a schematic.He will explain it better than a book,as you can aske him questions and he will give you an answer but the book will not. Barry.
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    motor control

    tjnomad If you can limit the output voltage to 24vdc then yes I can see no problem in this.But dont forget you must not exceed the 24cdc.Also will your controler supply the current.Also why dont you just get the correct controler. Barry.
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    reactors and capacitors

    Hi cameronUK Tests performed on reactoer are henerys or uh. these are just checks on values. Caps are checked or tested by uf readings, or in the case of vars. you would check the resistance the manufacturer would tell you what value you should have.caps for pf are fused internally and you can...
  5. laundry

    Universal motors

    Hi Gunnar. I was off yesterday.I Have worded it badly the increase in speed was related to a standard ac motor frequency increase.As you have pointed out universal motors are not frequency dependent correct.Series motors for use on ac,supplies are always designed with fully laminated...
  6. laundry

    Universal motors

    Alberto8 At 60hz rpm= 3600. At 50hz rpm= 3000 The current will change direction every 10ms and a peak in torque 100 times per second.But the torque willalways remain undirectional,and the speed fluctuations will not be noticeable because of the amoothing effect of the armature inertia...
  7. laundry

    Correct motor termination

    Hello Hewlett The correct way is flat washer first then spring washer or star washer then nut. This is to allow the nut to rotate on the spring or star washer and not on the flat washer, thus evading the lug from being rotated by the flat washer. Barry.
  8. laundry

    Universal motors

    Aiberto8 What type of motor are you talking about is it ac or dc,as you have indicated series and compound.series and compound are DC. skogsgurra is right what is the question. Barry.
  9. laundry

    12v 40 amp power supply

    skogsgurra yes you are right have made a complete fool of myself. so I will BANISH MYSELF for today. Barry.
  10. laundry

    12v 40 amp power supply

    Before you all have ago at me, yes I have worked out the trany for 24v and not 12v the truck bat threw me. the correct trany is 600va and 11vac sec. rectified will give you 21.54cdc. Barry.
  11. laundry

    12v 40 amp power supply

    Ignor the 25vac sec it should be 22vac sec. Barry.
  12. laundry

    12v 40 amp power supply

    Hi gmh265 Try this company XP Plc. sales:@xpplc.com Tel+44(0)1189845515 They manufacture and supply switch mode power supplies,they will even supply to your request. But why dont you just make your own supply with a transtormer say 1kva 25vac sec will give you 40amps.a bridge rectifier two...
  13. laundry

    Star delta motor for the same power

    Hi aolalde Yes I stand corrected my mistake. Barry.
  14. laundry

    FLA Rating calculation on stand alone rbt mig welding cells

    WIRESRCROSSED. Im not quite sure what you are getting at but a 75kva load roughly is 130amps ie 75000/575=130amp. Iwould think the manufacturer as stated that the systems requirements are 75kva on FL. So your disconnector and fusing are designed for this potential load. Not mush point fitting...
  15. laundry

    Torque limit and Control

    Hello maypot You canot have torque control in v/f because in torque control the current demand is connected to the current PI controller giving closed loop torque/current control. the current error is passed through proportional and integral terms to give a frequency ref Barry.
  16. laundry

    encoder monitorig

    itsmoked What are you talking about he said he as a 1024 pulse encoder do-hicky. Barry.
  17. laundry

    Terms

    HI Motortester. Have read your last coment I think this is what you are looking for ie If the motor runs in the wrong direction, change over L1 with L2 this will change rotation,But if your motor is a star/delta and the motor stalles when changed to delta you have the same phase ie red to red on...
  18. laundry

    encoder monitorig

    Hi bigheadted, This is quite an easy fault to find, first check your supply to the encoder with a scop pref 20mhz.It must have no spikes or noise on it, Second look at the output pulses these must be perfectly square if you under stand what i mean and have no spikes or ripples any were. check...
  19. laundry

    Rated torque above rated speed for different load types

    Hi DriveMaster Increasingthe speed from 50HZ to57HZ Increasing the speed of the inverter will continue to raise the output frequency although the voltage supplied to thr motor cannot increase, being limited to the level of the incoming line supply. The motor will increase in speed responding to...
  20. laundry

    Star delta motor for the same power

    Hello DriveMaster. I have read all the above answers to your simple question. If you have a 50kw motor 380v 1000rpm. One motor is star rated at 50kw 380v 1000rpm.The other motor is delta rated at 50kw 380v 1000rpm. the manufacturer has designed thse motors to run on these connections,it is still...
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