FANOX SIL-A A Series, User Manual

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4.9 Function 46BC. Broken conductor detection
This protection function can be set by using the following parameters:
Function Description Minimum Maximum Step Unit Default
46BC (*) Broken conductor protection
Function Enable - - No/Alarm/Trip - No
Current tap 15 100 1 % 50
Time Delay 0.020 300.000 0.001 s 0.200
(*) Optional depending on model
This protection detects the percentage phase unbalance due to an open phase condition. It considers
the measurement I2/I1 in percentage.
If the measured relation between I2 and I1 is higher (in percentage) than the setting in the function during
the adjusted time, the function will trip.
The function activates at 100% of the preset input and deactivates at 95%. The reset is instantaneous.
The accuracy of the time delay is equal to the set time delay ±30ms or ±0.5% (whichever is greater).
4.10 Function 49. Thermal Overload
This protection function can be set by using the following parameters:
Function Description Minimum Maximum Step Unit Default
49 Thermal overload
Function Enable - - No/Alarm/Trip - No
Current Tap 0.100 2.400 0.001 xIn 1.200
ζ Heating constant 3 600 1 min 3
Cooling constant 1 6 1 ζ heating 1
Alarm 20 99 1 % 80
Thermal image is a measurement of heating and cooling of an electric machine. Contrary to an
overcurrent protection time is not counted when a fault is detected. It continues calculating the thermal
status of the monitored machine. Tripping time depends on adjusted thermal constants, operative
current and previous thermal status of the machine.
Thermal image is calculated based on next equation:
θ = 100 x (I/It)
2
x (1 – e-t/ ζ ) + θ’0 x e -t/ ζ