Monitoring Functions; Metering And Recording - Toshiba GRD110 Manual

GRD110

MONITORING FUNCTIONS

Trip Circuit Supervision
The circuit breaker tripping control circuit can be
monitored by a binary input. Figure 3 shows a typical
scheme. When the trip circuit is complete, a small
current flows through the binary input, the circuit breaker
auxiliary contacts and the trip coil. This current flows
for both the breaker open and closed conditions.
GRD110
+ve Trip Trip Output
Suppl y
Binar y
Input
Figure 3 - Illustration of Trip Circuit Supervision
Scheme
If the trip supply is lost or if a connection becomes
open circuit then the binary input resets and a Trip
Circuit Fail alarm is given in the form of an output
contact operation and LCD or LED indication.
Automatic Self-Supervision
Automatic monitoring of internal circuits and software
is provided. In the event of a failure being detected,
the ALARM LED on the relay fascia is illuminated, the
'RELAY FAILURE' binary output operates, and the
date and time of the failure is recorded in the event
record.
Circuit Breaker State Monitoring
If two binary inputs are programmed to the functions
'CB OPEN' and 'CB CLOSED' then the CB State
Monitoring function becomes active. In normal
circumstances these inputs are in opposite states. If
both show the same state then a 'CB Defective' alarm
is raised.
Circuit Breaker Condition Monitoring
The following CB condition monitoring functions are
provided:
The trip counter increments the number of tripping
operations performed. An alarm is issued when
the count exceeds a user-defined setting.
y
The I counter increments the value of
current to the power 'y', recorded at the time of
issuing the tripping signal, on a phase by
phase basis. An alarm is issued when the count
for any phase exceeds a user-defined setting.
This feature is not available in GRD110-110.
The operating time monitor records the time
between issuing the tripping signal and the phase
currents falling to zero. An alarm is issued when
Circuit Breaker
CB Trip Coil -ve Tri p
Suppl y
CB Aux.
Contac ts
the operate time for any phase exceeds a user-
defined setting.
The CB condition monitoring functions are triggered
each time a trip is issued, and they can also be triggered
by an external device via a binary input.

METERING AND RECORDING

Metering
The following data is continuously available on the
relay fascia LCD and at a local or remote PC.
Primary and secondary currents for each input.
Positive and negative phase sequence
currents (only available in 3 phase models).
Ratio of negative phase sequence to positive
phase sequence currents.
Power frequency.
Peak phase current demand.
Thermal condition of system.
Relay element output status.
Binary input and output status.
Event Record
Records are stored for the 480 most recent events,
time-tagged to 1ms resolution. The event record is
available on the relay fascia LCD and at a local or
remote PC. Events are recorded as follows:
Tripping operations.
Alarms.
Operation of protection elements.
Change of state of binary inputs / outputs.
Change of relay setting.
Failure detected by automatic supervision.
Fault Record
A relay trip initiates fault recording. Records are stored
for the 8 most recent faults, time-tagged to 1ms
resolution. The fault record is available on the relay
fascia LCD and at a local or remote PC. Fault records
include the following data:
Date and time of trip operation.
Operating phase.
Protection scheme responsible for trip.
Measured current data.
Disturbance Record
The relay can record 8 analog and 32 binary signals,
initiated by relay tripping. The post-trigger recording
time can be set, and the maximum number of records
which can be stored is dependent on the recording
time chosen.
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