FANOX SIL B, Руководство пользователя

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4.
PROTECTION FUNCTIONS
4.1. Functions 50_1 and 50_2. Instantaneous phase overcurrent
This protection function can be set by using three parameters:
Function Description Minimum Maximum Step Unit Default
50_1
50_2
Instantaneous phase overcurrent
Permission - - Yes/No - No
Tap 0.10 30.00 0.01 Inominal 5.00
Operating time 0.02 300.00 0.01 s 0.02
The operating time is independent from the operating current flowing through the equipment, so if the
phase current exceeds its predetermined value for an equal or greater amount of time than this preset
value, the protection function activates (trips) and does not reset itself until the average value of the
phase drops below the point of current pick-up.
The function activates at 100% of the preset input, and deactivates at 95%. The reset is instantaneous.
The accuracy of the operating time is equal to the preset time plus a maximum of 30 ms.
4.2. Function 67_1 & 67_2. Inverse-time phase directional overcurrent
Two phase directional units are available: 67_1 y 67_2.
This function uses the cross phase voltage as a polarization magnitude and the phase current as an
operating magnitude. The intervention sector is defined in the following way: the operating angle is
rotated anticlockwise from the polarization voltage, which gives us the maximum torque direction. A
cone is drawn, with the half-cone angle adjusted, over this maximum torque direction.
If the directionality option is not activated, the 67 function behaves like a 51P/50 function.
The actuation time starts when the following conditions are met simultaneously:
•
Polarization voltage higher than adjusted
•
Phase current higher than adjusted
•
The phase shift of phase current and polarization voltage is such that the phase current is
inside the intervention sector.