Areva MiCOM P225, Technical Manual

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P225/EN FT/B11 User Guide
Page 36/52 MiCOM P225
A parameter setting group change is not possible if one of the following protection functions
is in progress (that is to say if the current threshold of these functions is exceeded):
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[50/51] SHORT CIRCUIT function
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[50N/51N] EARTH FAULT function
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[46] UNBALANCE function
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[27] UNDERVOLTAGE function
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[59] OVERVOLTAGE function
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[48] EXCES LONG START function
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[50S/51LR] BLOCK ROTOR function
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[37] LOSS OF LOAD function
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[49/38] RTD probe function
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[49] THERMISTANCE function
4.11.4.2.3 Speed switch device
A logic input set on SPEED SW can be connected to a speed sensor usually known as a
“ speed switch ”.
The “ speed switch ” should be open when the rotor is not turning and should close as soon
as it detects rotor rotation. The connecting of this logic input to a “ speed switch device ” is
necessary in order to be able to use the “ locked rotor at start ” protection function.
N.B.: When no logic input is set to "SPEED SW", the "Locked rotor at start-
up" function (refer to chapter 4.10.8.2) cannot be used, it must
therefore be deactivated.
4.11.4.2.4 Trigging of the disturbance recording
By assigning the command “ DIST TRIG ” to a programmable logic input, the operator will be
able to initiate the disturbance recordings (RECORD menu) from this input. The energising
(rising front) of this programmed logic input on “ DIST TRIG ” will trigger a disturbance
recording.
4.11.4.2.5 External acknowledgement
By dedicating a logic input to the external acknowledgement command “ EXT RESET ”, the
operator can acknowledge the alarms and unlatch the output relays if the latter were kept
energised (see sections 4.11.8 and 4.11.10), by energising this logic input.
4.11.4.2.6 Auxiliary 1 and auxiliary 2 data
The “ EXT1 ” and “ EXT2 ” assignments allow relay P225 to acquire two lots of external
binary data. A time delay (t EXT 1 and t EXT 2 respectively) is linked to each assignment.
The internal “ EXT1 ” signal to the relay is in logic state 1 if the associated logic input is
energised for a time longer or equal to t EXT 1 time delay. When the logic input is no longer
energised, the logic state of the internal ” EXT1 ” signal drops back to 0.
The internal “ EXT2 ” signal to the relay is in logic state 1 if the associated logic input is
energised for a time longer or equal to t EXT 2 time delay. When the logic input is no longer
energised, the logic state of the internal ” EXT2 ” signal drops back to 0.
When the t EXT 1 and t EXT 2 timers expire, the following happen:
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an alarm message is sent
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the Alarm LED is lit
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an event is recorded.