GE C30 Instruction Manual page 387

CHAPTER 5: SETTINGS
Assume that Phase Instantaneous Overcurrent 1 is used by Devices 2, 3, and 4 to block Device 1. If not blocked, Device 1
trips the bus upon detecting a fault and applying a short coordination time delay.
The following settings are applied (assume Bit 3 is used by all 3 devices to send the blocking signal and Direct Inputs 7, 8,
and 9 are used by the receiving device to monitor the three blocking signals).
UR IED 2:
: "PHASE IOC1
DIRECT OUT 3 OPERAND
UR IED 3:
: "PHASE IOC1
DIRECT OUT 3 OPERAND
UR IED 4:
: "PHASE IOC1
DIRECT OUT 3 OPERAND
UR IED 1:
: "2"
DIRECT INPUT 7 DEVICE ID
DIRECT INPUT 7 BIT NUMBER
DIRECT INPUT 7 DEFAULT STATE
: "3"
DIRECT INPUT 8 DEVICE ID
DIRECT INPUT 8 BIT NUMBER
DIRECT INPUT 8 DEFAULT STATE
: "4"
DIRECT INPUT 9 DEVICE ID
DIRECT INPUT 9 BIT NUMBER
DIRECT INPUT 9 DEFAULT STATE
Now the three blocking signals are available in UR IED 1 as
communications or a device, the scheme is inclined to block (if any default state is set to "On"), or to trip the bus on any
overcurrent condition (all default states set to "Off").
Example 3: Pilot-aided schemes
Consider a three-terminal line protection application shown in the following figure.
Assume the Hybrid Permissive Overreaching Transfer Trip (Hybrid POTT) scheme is applied using the architecture shown as
follows. The scheme output operand
C30 CONTROLLER SYSTEM – INSTRUCTION MANUAL
OP"
OP"
OP"
: "3"
: select "On" for security, select "Off" for dependability
: "3"
: select "On" for security, select "Off" for dependability
: "3"
: select "On" for security, select "Off" for dependability
DIRECT INPUT 7 ON
Figure 5-100: Three-terminal line application
is used to key the permission.
HYB POTT TX1
, , and
DIRECT INPUT 8 ON DIRECT INPUT 9 ON
INPUTS/OUTPUTS
. Upon losing
5
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