GE 750, Instruction Manual

Page: 226 / 504

13-
10
750/760 Feeder Management Relay GE Power Management
13.4 DEMAND 13 S6 MONITORING
13
13.4.2 CURRENT DEMAND
The current demand for each phase is calculated individually, and the demand for each phase is monitored by
comparing to a single current demand pickup value. If the current demand pickup is exceeded by any phase,
the relay can cause an alarm or signal an output relay.
■
CURRENT
■
[ENTER] for more
The
CURRENT
Demand setpoints path is:
\ SETPOINTS \ S6 MONITORING \ DEMAND \ CURRENT
CURRENT DEMAND
FUNCTION: Disabled
Range: Disabled, Alarm, Latched Alarm, Control
Selects the required function.
MEASUREMENT TYPE:
Thermal Exponential
Range: Thermal Exponential, Block Interval, Rolling Demand
Select one of three current demand calculation methods.
THERMAL 90% RESPONSE
TIME: 15 min
Range: 5 min, 10 min, 15 min, 20 min, 30 min, 60 min
This message is only displayed if the
MEASUREMENT TYPE
is selected as
Ther-
mal Exponential
. Enter the time required for a steady state current to indicate
90% of the actual value. This setpoint allows the user to approximately match
the response of the relay to analog instruments.
TIME INTERVAL:
20 min
Range: 5 min, 10 min, 15 min, 20 min, 30 min, 60 min
This message is only displayed if the
MEASUREMENT TYPE
is selected as Block
Interval or Rolling Demand . Enter the time period over which the current
demand calculation is to be performed.
CURRENT DEMAND
RELAYS (3-7):-----
Range: Any Combination of the 3-7 AUXILIARY Relays
Select the output relays required.
CURRENT DEMAND
PICKUP: 1000 A
Range: 10 to 10000 in steps of 1 A
Enter the threshold value for current demand. For example, if an action is
required when the current demand is above 1000 A, enter
1000
for this set-
point. When the maximum current demand in any phase exceeds this setting,
the programmed action will be performed.