Signal Sources - GE M60 Instruction Manual

SYSTEM SETUP

5.5.3 Signal sources

SETTINGS  SYSTEM SETUP  SIGNAL SOURCES  SOURCE 1(4)
 SOURCE 1

Identical menus are available for each source. The "SRC 1" text can be replaced by with a user-defined name appropriate
for the associated source.
The first letter in the source identifier represents the module slot position. The number directly following this letter
represents either the first bank of four channels (1, 2, 3, 4) called "1" or the second bank of four channels (5, 6, 7, 8) called
"5" in a particular CT/VT module. See the Introduction to AC Sources section at the beginning of this chapter for details.
It is possible to select the sum of all CT combinations. The first channel displayed is the CT to which all others are referred.
For example, the selection "F1+F5" indicates the sum of each phase from channels "F1" and "F5," scaled to whichever CT
has the higher ratio. Selecting "None" hides the associated actual values.
The approach used to configure the AC sources consists of several steps; first step is to specify the information about each
5
CT and VT input. For CT inputs, this is the nominal primary and secondary current. For VTs, this is the connection type, ratio
and nominal secondary voltage. Once the inputs have been specified, the configuration for each source is entered,
including specifying which CTs are summed together.
5.5.3.1 User selection of AC parameters for comparator elements
CT/VT modules automatically calculate all current and voltage parameters from the available inputs. Users must select the
specific input parameters to be measured by every element in the relevant settings menu. The internal design of the
element specifies which type of parameter to use and provides a setting for source selection. In elements where the
parameter can be either fundamental or RMS magnitude, such as phase time overcurrent, two settings are provided. One
setting specifies the source, the second setting selects between fundamental phasor and RMS.
5.5.3.2 AC input actual values
The calculated parameters associated with the configured voltage and current inputs are displayed in the current and
voltage sections of actual values. Only the phasor quantities associated with the actual AC physical input channels display
here. All parameters contained within a configured source are displayed in the sources section of the actual values.
5.5.3.3 Example for use of sources
An example of the use of sources is shown in the following figure. A relay can have the following hardware configuration:
Increasing slot position letter -->
CT/VT module 1
CTs
This configuration can be used on a two-winding transformer, with one winding connected into a breaker-and-a-half
system. The following figure shows the arrangement of sources used to provide the functions required in this application,
and the CT/VT inputs that are used to provide the data.
5-116
SOURCE 1 NAME:

SRC 1
SOURCE 1 PHASE CT:

None
SOURCE 1 GROUND CT:

None
SOURCE 1 PHASE VT:

None
SOURCE 1 AUX VT:

None
CT/VT module 2 CT/VT module 3
VTs not applicable
Range: up to six alphanumeric characters
Range: None, F1, F5, F1+F5,... up to a combination of
any 6 CTs. Only Phase CT inputs are displayed.
Range: None, F1, F5, F1+F5,... up to a combination of
any 6 CTs. Only Ground CT inputs are displayed.
Range: None, F5, M5
Only phase voltage inputs are displayed
Range: None, F5, M5
Only auxiliary voltage inputs are displayed
M60 MOTOR PROTECTION SYSTEM – INSTRUCTION MANUAL
CHAPTER 5: SETTINGS