Alternator test certificates

[sen2506]

We are purchasing an alternator of 2.5MW a standard model from Cummins for a client , Client is asking for type test certificate for this alternator model which the manufacturer says they do not have. They are listing out the Routine tests that are done in an alternator as apart of acceptance tests in the Factory. We also explained that the tests like Lightning impulse test, short circuit tests are not normally done as part of Routine test but the manufacturer should definitely having this conducted for this model to establish their design and will be having this certificate.

Whether my understanding is correct?

Thanks to clarify.

 

[edison123]

There is no lightning impulse test for rotating machines, it is only for transformers which are connected to the grid.

Muthu

http://www.edison.co.in

 

[cuky2000]

The following items provide a brief overview of regarding Impulse Voltage Strength applicable to AC Rotating Machines:
_{1) Instead of a "Lightning impulse test, (BIL)" most standards recognize the typical "impulse Voltage Withstand Envelope" (See graphs below)
2) The following thread238-156710 reemphasize this statement.
3) Regarding the short circuit test, it is possible to obtain sequence impedances and transient, sub transient and steady states impedances to determine the short circuit as shown in the following Link
4) Enclosed are two prototype test reports, 1) 230 kVA Link & 2) 500 kW [link file:///C:/Users/picha001/Downloads/0197890SSD.pdf]Link[/url] for typical small gent sets units.
5) The sketch below provides an illustration of typical Rotating Machine withstand data.}
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