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Difference between 40Q (Var) and 40Z (mho type)

Thread starter obut4
Start date Aug 29, 2007

Status: Not open for further replies.

Aug 29, 2007

obut4

Electrical

Hi,

I'am new on this forum.
For generator protection, I would like to know what difference can be made between a 40Q and a 40Z loss of excitation protection?
40Q: is a loss of excitation protection that monitors the VAR flow.
40Z: is an impedance based loss of excitation protection.

What are the advantages and drawbacks of each method?
Which one is better and why?

Thank for your help