GE Multilin T60 settings question

[lz5pl]

GE Multilin relays are not popular here and we haven't experience with them. Local utility has several Multilin relay protections installed by foreign contractor. They had several wrong trips of transformer differential protection T60 during out-of-zone ground faults. During inspection of settings today we found that it is wrongly set the following transformer parameter: Winding 3/ Grounding/ Not within zone. Actually that winding has solidly grounded neutral point. Parameter was changed accordingly to: Within zone, what I hope should resolve the problem.
But my question is for the next parameter: Winding 3/Resistance. Default value for this parameter is 10 Ohms. I suppose it is resistance of the neutral grounding, and in our case (solidly grounded) it should be set to 0 Ohms. But in the Manual for T60 I cannot find any explanation about that parameter.
Could somebody with experience with that protection help me with understanding of this parameter ?

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It may be like this in theory and practice, but in real life it is completely different.
The favourite sentence of my army sergeant

 

[ePOWEReng]

The resistance setting you are referring to is not the neutral grounding. The setting is supposed to be the winding resistance of the transformer. This is not used for "typical" protection elements (i.e. transformer differential or o/c elements). It can be used in thermal calculations using the T60 relay. This setting doesn't affect the differential element operation.

 

[DTR2011]

If I recall correctly, the winding resistance is a setting related to a thermal model, not a differential protection setting. This would be from factory test data of the transformer DC resistance.

 

[rcw retired EE]

I agree with these other fine engineers. It is only used in life evaluation calculation.
We seldom set that function. We just leave it at the default 10 ohm. If the client wants to use that feature, they can dig up the data and program the relay.

 

[lz5pl]

Thank you all for fast responses. It means that my setting for neutral grounding is sufficient and I should not go again to the site. Strange, but this parameter is not well explained in the Manual, which otherwise seems quite detailed.

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It may be like this in theory and practice, but in real life it is completely different.
The favourite sentence of my army sergeant