Protection & Control
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Dear All,
I have doubt in Thermal overload (ANSI 49 M) Protection in the relay P5M30.
how to calculate Current based setting mode time constants with examples :
1. Heating time constant/ Time constant Ʈ1
2. Time constant for motor starting /Time constant Ʈ2
3. Cooling time constant/ Time constant Ʈ3
In manual Equations available but how to calculate the values examples not available in page no : 323 & 324 in the manual P5/EN M/44C
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Hello,
question is not very clear to me.
The different time constants have to be provided from the motor manufacturer.
The calculation of thermal replica in P5 then is done based on these setting data and the measured currents.
JinLei had posted in this forum an excel application to visualize the operation, which may help:
Please add further details, if this does not answer your question.
best regards
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Hi Simon,
We need example calculations how to calculate the following time constants, in manual only equations given, what values we need to submit to find the constants, we want to know, please clarify.
1. Heating time constant/ Time constant Ʈ1
2. Time constant for motor starting /Time constant Ʈ2
3. Cooling time constant/ Time constant Ʈ3
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I second what was said previously : those data shall be inputs data to any product configuration and must be provided in the machine's datasheet.
Ultimately, it is the motor designer recipe to calculate that and it falls beyond the art of protection settings.
Should you still wish or need to dive deeper, I would recommend to check IEC 60034, mainly parts 1,11 and 29. those norms provide insight on what and how to test machines with respect to their thermal behavior.
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Hi,
The below link i cant able to open,
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the above windows coming when i opening the link.
My question was how to calculate the values for below time constants :
1. Heating time constant/ Time constant Ʈ1
2. Time constant for motor starting /Time constant Ʈ2
3. Cooling time constant/ Time constant Ʈ3
which we need to give during the relay setting, when we chose current based setting mode in Thermal overload protection for machine (ANSI 49M)
If any calculation examples given in manual means it is very useful for us, please help...
I have attached the manual for P5M30 also for your reference.
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