Variable frequency inverter connections

Check the motor rating plate bud,it will tell you the connection you need.some people seem to think they all need conneting Delta but this is not so.

I always use SY to connect motors to VFD's , make sure you bond the braid to earth if you use it and check the VFD's manual for max distance of cabling to motor.

Chris

heres a bank of 30 vfd's i've just put into service at a local recycling plant


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chrisb271 said:

Check the motor rating plate bud,it will tell you the connection you need.some people seem to think they all need conneting Delta but this is not so.

I always use SY to connect motors to VFD's , make sure you bond the braid to earth if you use it and check the VFD's manual for max distance of cabling to motor.

Chris

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I Have come up against the same problem. The motor rating plate gives values for Star and Delta but does not tell you which connection to use with the Inverter, neither does the Drive Manual.

charlietech said:

I am looking to replace a 7.5KW (10HP) AC 3 phase motor and Variable Frequency drive. I have selected a Eurotherm 650 3 phase 7.5KW and a SEM 7.5KW motor as they were on stock locally, I was wondering how should the motor be connected, should it be wired star or delta. Any advice much appreciated.

Charlie.

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Well wire it up delta heres why STAR /DELTA star is reduced voltage start and delta is full voltage applied to motor meaning wire up your motor for a delta full running tap .

Thats why they made freq drives to not have a need to star start /delta run it kinda ramps up the motor speed for you .

Dont know what or how your drive is made or any info about it ?
What is your type of drive ? Take care

charlietech said:

I am looking to replace a 7.5KW (10HP) AC 3 phase motor and Variable Frequency drive. I have selected a Eurotherm 650 3 phase 7.5KW and a SEM 7.5KW motor as they were on stock locally, I was wondering how should the motor be connected, should it be wired star or delta. Any advice much appreciated.

Charlie.

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You'd better check the manual of the motor firstly. This is the safest way before you connect.

And you'd be careful to read the manual of VFD too.

if convenient, I will recommend you to contact the manufacturer for details. You should not connect as you like.