Variable Speed drive application
Variable Speed drive application
(OP)
I am currently working on the design of a chemical injection skid for offshore use. We have designed the unit to run from a 400V 50Hz supply. There are two motors on this unit. These are coupled to geared pumps. My client has now stated that the unit should run from the following supplies:
400V 50Hz
400V 60Hz
450V 50Hz
450V 60Hz
The pumps cannot operate at the higher speed.
The motors are EExde, 55kW
Would a VSD overcome this operation by setting it so it always outputs 400V 50Hz? The on board PLC on the skids will provide a volt-free contact to start and stop the pump.
I have not used VSDs before so any advice would be most welcome
400V 50Hz
400V 60Hz
450V 50Hz
450V 60Hz
The pumps cannot operate at the higher speed.
The motors are EExde, 55kW
Would a VSD overcome this operation by setting it so it always outputs 400V 50Hz? The on board PLC on the skids will provide a volt-free contact to start and stop the pump.
I have not used VSDs before so any advice would be most welcome





RE: Variable Speed drive application
I have used AB drives extensively on machines for export. Though you do need to program into the drive what the input voltage will be. It still works if you don't it just incorrectly scales the speed.
RE: Variable Speed drive application
So if i get this correct:
I connect my three phase incoming supply, what ever it may be and manually set the output at the VSD control panel? So as long as the procedures to do this are outline all should be ok?
RE: Variable Speed drive application
RE: Variable Speed drive application
Also, if the pumps need to turn on independantly of one another, each one will need to have its own VFD. You can use one VFD as a sigle power source, but then everything connected to it must be started and stopped by the VFD all at the same time.
"Venditori de oleum-vipera non vigere excordis populi"
RE: Variable Speed drive application
I intend to use two drives. I spoke to ABB Drives who say that their ACS 800 500V series is suitable. I always want to put a 400V 50Hz supply out so as such I will never be using it to generate a 440V supply. Am I correct?
RE: Variable Speed drive application
Think of a VFD as being a new power source that you get to program as to voltage and frequency. Incoming power is nothing more than the "raw material" feeding the new power source. As long as that raw material meets basic requirements such as minimum voltage (in your case 400V) and adequate current availability, it will produce whatever you tell it to.
Just as a comment, the ACS-800 might be a bit of an overkill if you are not going to use it to change the motor speed at all. Nothing wrong with the drive, but it is designed for much more complex and demading applications. If all you want is a variable input power source, you could likely do much better economically. Then again, if your end user is comfortable with ABB and uses them elsewhere on his platform, it may be a good idea from a familiarity standpoint.
"Venditori de oleum-vipera non vigere excordis populi"
RE: Variable Speed drive application
Thanks for the info