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Micrologic control units
Micrologic P "power"
Micrologic P control units include all the functions
offered by Micrologic A.
In addition, they measure voltages and calculate power
and energy values.
They also offer new protection functions based on
currents, voltages, frequency and power reinforce load
protection in real time.
Long-time current setting and tripping delay.
1
Overload signal (LED).
2
Short-time pick-up and tripping delay.
3
Instantaneous pick-up.
4
Earth-leakage or earth-fault pick-up and tripping delay.
5
Earth-leakage or earth-fault test button.
6
Long-time rating plug screw.
7
Test connector.
8
Lamp + battery test and indications reset.
9
Indication of tripping cause.
10
High-resolution screen.
11
Measurement display.
12
Maintenance indicators.
13
Protection settings.
14
Navigation buttons.
15
Hole for settings lockout pin on cover.
16
Note:
Micrologic P control units come with a non-transparent
lead-seal cover as standard.
Protection........................................................
+
Protection settings
The adjustable protection functions are identical to those of Micrologic A (overloads,
short-circuits, earth-fault and earth-leakage protection).
Fine adjustment
Within the range determined by the adjustment dial, fine adjustment of thresholds (to
within one ampere) and time delays (to within one second) is possible on the keypad
or remotely using the COM option.
IDMTL (Inverse Definite Minimum Time Lag) setting
Coordination with fuse-type or medium-voltage protection systems is optimised by
adjusting the slope of the overload-protection curve. This setting also ensures better
operation of this protection function with certain loads.
Neutral protection
On three-pole circuit breakers, neutral protection may be set using the keypad or
remotely using the COM option, to one of four positions: neutral unprotected (4P 3d),
neutral protection at 0.5 Ir (4P 3d + N/2), neutral protection at Ir (4P 4d) and neutral
protection at 1.6 Ir (4P 3d + 1.6N). Neutral protection at 1.6 Ir is used when the
neutral conductor is twice the size of the phase conductors (major load imbalance,
high level of third order harmonics).
On four-pole circuit breakers, neutral protection may be set using a three-position
switch or the keypad: neutral unprotected (4P 3d), neutral protection at 0.5 Ir (4P 3d
+ N/2), neutral protection at Ir (4P 4d). Neutral protection produces no effect if the
long-time curve is set to one of the IDMTL protection settings.
Programmable alarms and other protection
Depending on the thresholds and time delays set using the keypad or remotely using
the COM option, the Micrologic P control unit monitors currents and voltage, power,
frequency and the phase sequence. Each threshold overrun is signalled remotely via
the COM option. Each threshold overrun may be combined with tripping (protection)
or an indication carried out by an optional M6C programmable contact (alarm), or
both (protection and alarm).
Load shedding and reconnection
Load shedding and reconnection parameters may be set according to the power
or the current flowing through the circuit breaker. Load shedding is carried out by
a supervisor via the COM option or by an M6C programmable contact.
Indication option via programmable contacts
The M6C (six contacts) auxiliary contacts may be used to signal threshold overruns
or status changes. They can be programmed using the keypad on the Micrologic P
control unit or remotely using the COM option (BCM ULP) and RSU software.
Communication option (COM)
The communication option may be used to:
remotely read and set parameters for the protection functions
b
transmit all the calculated indicators and measurements
b
signal the causes of tripping and alarms
b
consult the history files and the maintenance-indicator register.
b
maximeter reset.
b
An event log and a maintenance register, stored in control-unit memory but not
available locally, may be accessed in addition via the COM option.
DB128042
Functions and characteristics