Task
A Distance relay requires the circuit breaker status to perform correctly.
Solution
The test set CMC 256 offers a CB simulation, which emulates the action of the auxiliary contacts (52a / 52b) of a circuit breaker during tripping and closing.
The test Module CB Configuration is used to set up the parameters and the mode of operation for this CB simulation. Its intended use is for protection testing, whre certain relays need feedback from a CB for proper operation of the protection function.
The Advanced Distance test module serves to test the impedance measurement function of distance relays. This module models the transmission line protected by a distance relay. It is recommended that this module be used to test the distance function. A manual test of this function is possible, but can prove to be very laborious and time consuming.
Individual fault shots can be placed anywhere in the impedance plane with the single shot. The check test places shots at the impedance tolerance limits of each zone to verify that the reach is within the tolerance limits. The exact reach can be determined with the search test.
Because an automatic test should be carried out, use the OMICRON Control Center so that the test can then be integrated with the tests for all the auxiliary functions of a distance relay (e.g., Fusefail [or LOP], Manual Close [or SOTF], Auto-reclose, Powerswing detection, etc.).
The Advanced Distance module could also be used stand-alone.
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3.3.1 Wiring Between Relay and CMC
1. Connect the voltage inputs of the relay to the corresponding voltage outputs of the CMC.
2. Connect the current inputs of the relay to the corresponding current outputs of the CMC. Ensure that the current "outputs" of the relay, i.e. the output side of the current transformers, are connected together in a starpoint.
3. Connect the trip signal of the relay to binary input 1 and the close signal from the Close Control Switch on the protection panel to binary input 2 of the CMC.
3.3.2 Starting the OMICRON Control Center
Start the OMICRON Control Center from the Start Page by clicking OP E N
EM P T Y DO C U M E N T.
3.3.3 Setting up the Test Object
For configuration of your relay under test, the correspondingly named software function Test Object is used. Open Test Object with the pull-down menu item IN S E R T | TE S T OB J E C T. Alternatively, click the Test Object toolbar icon. In Test Object browse, access and edit the test object parameters.
A detailed description of Test Object and the closely related subject "XRIO" can be found in section 3 ”Setting up the Test Object” of the "Concept" manual, or in the online help under the --- Test Object --- entry of the table of contents.
Import an existing RIO or XRIO file by selecting FI L E | IM P O R T, or add the test object function "Distance" and define the distance protection-specific parameters as described in detail in ”Step 1: Define the distance protection parameters” on page 37 of this manual.
3.3.4 Configuring the Hardware
Specify the hardware configuration according to the wiring described in section 3.3.1 ”Wiring Between Relay and CMC”.
A detailed description of the Hardware Configuration can be found in the
"Concept" manual’s section 4 ”Setting Up the Test Hardware”, or in the online help under the --- Hardware Configuration --- entry of the table of contents.
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3.3.5 Inserting the CB Configuration Module
1. Click the C B CO N F I G U R A T I O N icon in the test modules tool bar or 2. select IN S E R T | TE S T MO D U L E and then select "OMICRON CB
Configuration".
Defining the binary inputs and outputs for the CB simulation
1. Select PA R A M E T E R S | HA R D W A R E CO N F I G U R A T I O N in the CB Configuration Module.
2. For the CB Configuration a ’Trip’ and ’Close CMD’ must be assigned to the binary inputs. For this example the ’Trip’ will be connected to the distance relay trip output and the ’Close CMD’ to the close control switch of the protection panel - Figure 3-19.
3. The binary outputs must also be confederated to provide the distance relay with the CB status - Figure 3-20.
Figure 3-19:
Binary Inputs
Figure 3-20:
Binary Outputs
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Defining the CB condition
1. Click the "Test View".
2. Select the "Initial State" of the circuit breaker (CB). If selected "Closed" the CB will be simulated closed via the Binary outputs configured as soon as the module is executed and the same with the "Open" selection.
3. Select "Simulation Active".
4. The CB can be set to return to the "Initial State" after a set period, this is helpful when a "Close CMD" is not available.
5. To edit the "Trip" and "Close" time delay period, select
PA R A M E T E R S | TE S T OB J E C T, click "CB Simulation" and edit the times in the fields displayed. For more information refer to the online help.
6. The module can now be closed by selecting FI L E | EX I T & R E T U R N T O
* .O C C.
Figure 3-21:
CB Configuration Test View
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3.3.6 Inserting an Advanced Distance Module
1. Click the AD V A N C E D DI S T A N C E icon in the test modules tool bar, or
2. select IN S E R T | TE S T MO D U L E and then select OMICRON Advanced Distance.
3. Add a shot as described in section ”Step 4: Defining a Shot Test” on page 46 of this manual.
4. Close the module and return to the Control Center document.
5. Run the complete test procedure by selecting the "Test All" button. The CB Configuration test module will set the CB simulation.
6. Then perform the shot test as defined in the Advance Distance module.
Figure 3-22:
OCC Document
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3.3.7 Viewing the results
1. Select the Signal View in the Advance Distance Module.
2. By using the cursors the change of circuit breaker status can be determined.
The breaker opened after the trip was received from the distance relay, Figure 3-23 (1), and closed again after the Close CMD was received, Figure 3-23 (2).
Figure 3-23:
Signal View
1 2
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4 Advanced Differential
The Advanced Differential software is a family of test modules for testing differential protection relays. Specific test modules were developed to test specific features of a differential relay: Diff Configuration, Diff Operating Characteristic, Diff Trip Time and the Diff Harmonic Restraint.
The Advanced Differential modules are typically used from within the OMICRON Control Center (OCC). The test modules are embedded as objects into the OCC test document.
The OCC test document allows multiple modules to be controlled together with sequential testing of the chosen protective functions. For example, all common settings for a specific device can be controlled globally and do not have to be entered for each successive test module.
The OCC test document provides the tests results and format of the data to be contained in the test report. This allows creation of a customized report that includes the test data, graphics, text fields and text editing by the user.
Once the test document is complete, the OCC will run the embedded tests and automatically include the results in the report.
The test document provides two functions:
• the test specifications or protocol, and
• the report format.
All test data is captured and maintained so the report format can be easily changed, saved, and reused at any time, thus making summary reports and detailed reports available from the same document.
Relay
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