Joined: 25 March 2010
I'm looking for some guidance on the do's and dont's of contactors and where they can be placed in motor circuits, and hope someone may be able to help.
I have a situation where I need to put remote reversing of a pump via a dialup RTU. Its been fine with Star Delta anfd DOL, as well as with some VSDs as there is sometimes a parameter option to enable reverse control.
However, I have a softstart that I want to reverse. I was going to put the reversing contactor on the line side but believe some units will detect phase rotation errors, therefore want to put the reversing contactor on the load side. The main question I have is; will a standard power contactor be suitable for the high frequency thyristor switching that a softstart delivers??
Any thoughts would be greatly appreciated?
Alex Gray IEng MIET
Joined: 17 May 2006
wouldn't you want to stop the pump before reversing it? If so, the output of the soft start would be zero, surely?