GE M60 UR Series, Instruction Manual

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GE Multilin M60 Motor Protection System 5-91
5 SETTINGS 5.2 PRODUCT SETUP
5
IED 1 to IED 2: 0.2 of power system cycle;
IED 1 to IED 3: 0.4 of power system cycle;
IED 1 to IED 4: 0.2 of power system cycle;
IED 2 to IED 3: 0.2 of power system cycle;
IED 2 to IED 4: 0.4 of power system cycle;
IED 3 to IED 4: 0.2 of power system cycle.
If one ring is broken (say TX2-RX2) the delivery times are as follows:
IED 1 to IED 2: 0.2 of power system cycle;
IED 1 to IED 3: 0.4 of power system cycle;
IED 1 to IED 4: 0.6 of power system cycle;
IED 2 to IED 3: 0.2 of power system cycle;
IED 2 to IED 4: 0.4 of power system cycle;
IED 3 to IED 4: 0.2 of power system cycle.
A coordinating timer for this bus protection scheme could be selected to cover the worst case scenario (0.4 of a power sys-
tem cycle). Upon detecting a broken ring, the coordination time should be adaptively increased to 0.6 of a power system
cycle. The complete application requires addressing a number of issues such as failure of both the communications rings,
failure or out-of-service conditions of one of the relays, etc. Self-monitoring flags of the direct inputs and outputs feature
would be primarily used to address these concerns.
EXAMPLE 3: PILOT-AIDED SCHEMES
Consider the three-terminal line protection application shown below:
Figure 5–21: THREE-TERMINAL LINE APPLICATION
A permissive pilot-aided scheme could be implemented in a two-ring configuration as shown below (IEDs 1 and 2 constitute
a first ring, while IEDs 2 and 3 constitute a second ring):
Figure 5–22: SINGLE-CHANNEL OPEN LOOP CONFIGURATION
In the above application, the following settings should be applied. For UR-series IED 1:
DIRECT OUTPUT DEVICE ID:
“1”
DIRECT I/O CH1 RING CONFIGURATION:
“Yes”
DIRECT I/O CH2 RING CONFIGURATION:
“Yes”
For UR-series IED 2:
842713A1.CDR
UR IED 1
UR IED 2
UR IED 3
842714A1.CDR
UR IED 1
TX1
RX1
UR IED 2
RX2
TX2
RX1
TX1
UR IED 3
RX1
TX1