Distance Relay Logic Programming
GARD 8000 Distance Relay
RFL Electronics Inc.
SECTION 11.
DISTANCE RELAY
LOGIC PROGRAMMING
11.1
OVERVIEW
The GARD logic consists of two distinct parts; the System logic and the distance relay module logic.
The System logic handles the interaction between different modules in the GARD chassis. For
example: mapping of a physical input to a virtual input in the distance relay.
The System logic can also perform manipulations on the signals delivered to and from the distance
relay module. For example: providing trig points to the system SOE and latch of LED signals.
The System logic can be user programmed. This is described in a separate logic programming manual.
The section described here deals with programming inside the distance relay module only.
11.2
FACTORY DEFAULT PROGRAMMING
The GARD System is delivered with default programming of both the System logic and the distance
relay module logic, unless custom logic has been requested.
The following section describes the default programming of the distance relay module. For System
logic, please refer to the System manual and the System logic drawings supplied with the GARD.
Note that the distance module factory supplied system logic uses labels for all signals connected
between the system logic and the distance relay logic. This means that if the distance relay module is
reprogrammed, the corresponding label should be changed in the system logic as well.
11.3
INPUTS
The distance relay module has 70 pre-defined inputs. Some of these have logic associated with them.
11.3.1
BREAKER INPUTS (52 A OR 52 B)
The breaker input logic enables connection of one or two circuit breakers. The GARD “Option
settings” as described in the System manual are used to select single or dual breakers, 52a or 52b
inputs. These settings need to be correct for the corresponding virtual input 52b to be supplied to the
distance relay.
March 1, 2009
11-1
973.334.3100
