Voltage sags BLIPS causing production issues 1

[eewanabe]

I understand power BLIPS are weather related issues and are often the cause for PLC's, motors and drives to drop out.

Anyone actual use a sag mitigation device to ride through dirty power; what do you recommend?

Thanks in advance!

 

[Laplacian]

The question is pretty general. First, you have to get process input on what exactly they need to ride through.

For motors, there are several options to ride through blips between 5-20 cycles. You can employ an auto-restart relay or reacceleration scheme, latching contactors, or power circuit breakers depending on motor size and design philosophy you want to go with. Alternatively, you can supply the motor starter control circuit with CVT's (constant voltage transformers), but they are pricey.

For PLC's/Computers, they are a little more forgiving to blips than the inductive loads of contactor coils. If you must give them ride-through capability for momentary blips, the same CVT concept would apply. For longer disturbances, UPS is the answer. Note that there are many UPS topologies and application principles.

 

[ScottyUK]

Cross-posted from PLC forum and motors forum.


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One day my ship will come in.
But with my luck, I'll be at the airport!

 

[RalphChristie]

In some of our plants we use voltage dip-proofing inverters for the motors:

http://www.dipproof.com/

I can't really comment on how good they are - not much involved with it - but there are mixed feelings between the different sections using it. Some say it helped a lot in their areas, while others want to get rid of it.

Maybe other forum-members can comment on their experience with it.

Regards



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