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A-8
1
long-time threshold and tripping delay
2
overload alarm (LED)
3
short-time pick-up and tripping delay
4
instantaneous pick-up
5
fixing screw for long-time rating plug
6
test connector
Protection
Protection thresholds and delays are set using the adjustment dials.
Overload protection
True rms long-time protection.
Thermal memory: thermal image before and after tripping.
Setting accuracy may be enhanced by limiting the setting range using a different
long-time rating plug.
Overload protection can be cancelled using a specific LT rating plug "Off".
Short-circuit protection
Short-time (rms) and instantaneous protection.
Selection of I
2
t type (ON or OFF) for short-time delay.
Earth-fault protection
Residual or source ground return earth fault protection.
Selection of I
2
t type (ON or OFF) for delay.
Neutral protection
On three-pole circuit breakers, neutral protection is not possible.
On four-pole circuit breakers, neutral protection may be set using a three-position
switch: neutral unprotected (4P 3d), neutral protection at 0.5 Ir (4P 3d + N/2) or
neutral protection at Ir (4P 4d).
Indications
Overload indication by alarm LED on the front; the LED goes on when the current
exceeds the long-time trip threshold.
Test
Amini test kit or a portable test kit may be connected to the test connector on the
front to check circuit-breaker operation after installing the trip unit or accessories.
Micrologic 2.0, 5.0 and 6.0 control units protect power
circuits. Micrologic 5.0 and 6.0 offers time
discrimination for short-circuits as well.
Note.
Micrologic control units are equipped with a transparent lead-
seal cover as standard.
Micrologic control units
For Compact NS630b to 3200
DB128030
Functions and characteristics