TAVRIDA ELECTRIC ISM Shell_2 Series, Applications Manual

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Bas ic functions for all control modules
Charging of the Capacitors
Closing and trip capacitors of the CM are charged when CM is applied to the auxiliary power supply. The charged
closing capacitors correspond with the charged springs of a conventional circuit breaker. After the failure of
auxiliary power supply any pending trip or any trip command arriving to the CM up to 30s after failure of auxiliary
power supply will be executed.
Ready-LED and Ready-Relay Output
While charging the capacitors, the Ready-LED blinks. When the capacitors are charged the Ready-LED is
continuously lit and the Ready-relay output contact is closed. With a blinking or extinguished Ready-LED, the
Ready-relay output contact is open. The Ready-relay output can be used as a permissive, such as the release
condition for a breaker control.
Malfunction-LED and Malfunction-Relay Output
If the CM detects an internal or external malfunction, the Malfunction-LED will blink according to the type of
malfunction (see the “Signalling” chapter of this manual). At the same time the Malfunction-relay output contact
will close. In this way a CM-Malfunction state can be transmitted to an alarm or SCADA system. In the case of a
malfunction the Ready-LED is extinguished and the Ready-relay output contact is opened. The Malfunction-relay
output contact is closed if the CM is powered off.
Switching the ISM On and Off via the Dry Contact
Inputs of the CM
The ISM can only be closed electrically via the CM. Dry contact inputs are available on all CMs for
close and trip operations. Each of these inputs can be connected with one or more parallel-switched dry
contacts. Under no circumstances shall external voltage be applied to these inputs as this will destroy the
CM.
Electrical Clos ing Lock-Out
When the ISM manual trip hub is rotated to the locked position, an internal microswitch prevents close operation
of the breaker. As the hub is rotated counter-clockwise, the ISM is mechanically tripped (if closed) followed by the
microswitch disengaging the actuator connections. This prevents the breaker from closing until the trip hub is
rotated back to the unlocked position.