Reacceleration of motors

[maintennance]

In one of the pump data sheet , it has been indicated that the "Reacceleration of Motors to be provided for this pump. What exactly it mean. Is it the design aspect of the motor or a separate electronic control system to be built in to the power system for the motor supply? Any precautions to be taken for such pumps when the motor is given that provision? Thanks to clarify.

 

[waross]

Has the data sheet been translated from another language?

Bill
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"Why not the best?"
Jimmy Carter

 

[zeusfaber]

Anybody else feel this is trying to say that a direct online start risks shearing the shaft, so to use some sort of soft start?

A

 

[Skogsgurra]

Bill is probably right. A translation made by a translatator and not a technician.

The German expression "Wiederanlauf" means "Accelerate again" and there are, at least in Siemens inverters a so called WAA (WiederAnlaufAutomatik) or a WEA (WiederEinschaltAutomatik).

The option to start again after a power outage is important in many applications. And I think that it could be the meaning of "Reacceleration".

Does that make sense in your application?

Gunnar Englund

http://www.gke.org

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100 % recycled posting: Electrons, ideas, finger-tips have been used over and over again...

 

[jraef]

Does the pump system include a Variable Frequency Drive? It could mean that if there is a brief power failure, they want to VFD to be able to catch the spinning motor at any speed and re-accelerate it without needing to let it spin down first. In VFDs, a more common term is "Flying Restart". It's a very common requirement for some types of pump systems because if there are a lot of very brief power interruptions, i.e. grid switching, dips from starting larger loads nearby etc., they don't want the pump to need to shut down completely to restart. It is did, the check valve would close and might cause physical damage.


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