dlt27
-
- Joined
- Jul 4, 2011
- Messages
- 196
- Reaction score
- 26
Hi and thanks for any replies.
I am predominantly an install electrician and don't have a lot of experience dealing with motors so any help would be greatly appreciated.
I have been asked to connect a CNC machine, a dust extractor and a pump.
The CNC is straight forward as it is just connected to a rotary isolator, however the pump and extractor are just free standing motors and the name plates are in Chinese. I know the pump is 5.5 KW 3 phase and the extractor is 3KW 3 phase.
1. Am I right in thinking both should be wired through DOL starters with I think when calculated results in a 8.5A and 4.8A overloads with 0.9 power factor correction. (Guy who sold machines said rotary isolators were adequate for starting the motors)
2. Up to what size motors can a DOL starter be used.
3. How do I determine if they should be connected in Star or Delta as can't tell from name plate (What would happen if I connected them up wrong, ie connect in Delta and should be Star or vice versa?)
4. Am I right in thinking a DOL starter should always be used with motors because it provides protection to windings on start up and also it prevents motor restarting on power failure.
5. How do you determine if a Star Delta starter should be used with a motor?
Thanks again if you have got time to explain.
I
I am predominantly an install electrician and don't have a lot of experience dealing with motors so any help would be greatly appreciated.
I have been asked to connect a CNC machine, a dust extractor and a pump.
The CNC is straight forward as it is just connected to a rotary isolator, however the pump and extractor are just free standing motors and the name plates are in Chinese. I know the pump is 5.5 KW 3 phase and the extractor is 3KW 3 phase.
1. Am I right in thinking both should be wired through DOL starters with I think when calculated results in a 8.5A and 4.8A overloads with 0.9 power factor correction. (Guy who sold machines said rotary isolators were adequate for starting the motors)
2. Up to what size motors can a DOL starter be used.
3. How do I determine if they should be connected in Star or Delta as can't tell from name plate (What would happen if I connected them up wrong, ie connect in Delta and should be Star or vice versa?)
4. Am I right in thinking a DOL starter should always be used with motors because it provides protection to windings on start up and also it prevents motor restarting on power failure.
5. How do you determine if a Star Delta starter should be used with a motor?
Thanks again if you have got time to explain.
I