Manual 37138C
ESDR 4T - Current Differential Protection Relay
© Woodward
Page 19/46
Inputs and Outputs
≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡
Control Inputs
Configuration off
Terminal 17
When this input is energized, the unit remains in Display mode and cannot be
changed to Configuration mode. The Configuration mode is enabled if this terminal
is de-energized.
Acknowledgement
Terminal 18
If this input remains energized for at least 1 s, the faults detected in monitoring
level 2 are reset. This means that the relays will be de-energized and the text display
will be deleted from the screen as long as the monitored currents are not exceeding
the configured threshold level.
Blocking
Terminal19
When this input is energized, the differential protection is disabled. This means that
the differential current is not monitored, relays cannot be enabled and text is not dis-
played.
Relays
Relay 1
Terminals 1/2/3
The function of this relay may be configured. Refer to Configuring the Relay on
page 25 for details.
Relay 2
Terminals 4/5/6
The function of this relay may be configured. Refer to Configuring the Relay on
page 25 for details.
Ready for operation
(Relay 3)
Terminals 7/8
This relay is enabled when the unit is operational and the differential current is being
monitored. The relay becomes disabled if the monitoring is deactivated through any
of the following reasons:
•
the internal self-monitoring has detected a malfunction of the unit. A correct func-
tioning of the unit cannot be guaranteed and corrective action may be necessary.
•
the digital input "Blocking" is energized
•
the parameter "Monitoring" is configured to "Off"
An additional function may be assigned to this relay. Refer to Configuring the Relay
on page 25 for details.
Relay 4
Terminals 10/11/12
The function of this relay may be configured. Refer to Configuring the Relay on
page 25 for details.
