GE N60 - Digitizers

GE Multilin N60 Network Stability and Synchrophasor Measurement System 5-211
5 SETTINGS 5.7 CONTROL ELEMENTS
5
5.7.12 DIGITIZERS
PATH: SETTINGS  CONTROL ELEMENTS  DIGITIZERS  DIGITIZER 1(5)
There are five (5) digitizer elements. The digitizer truncates the input signal to user-specified symmetrical limits and digi-
tizes the outcome with an 8-bit resolution. The basic operation of the element is described by the following equations:
(EQ 5.18)
(EQ 5.19)
where: x is an input signal specified by the DIGITIZER 1(5) SOURCE setting
LIMIT is defined by the DIGITIZER 1(5) LIMIT setting
round is an operand that rounds up to the nearest integer
N
out
is an integer output of the digitizer (from –127 to 127)
The output characteristic of the digitizer element is illustrated below:
Figure 5–88: DIGITIZER OUTPUT CHARACTERISTIC
The output integer number is represented by eight (8) FlexLogic™ operands encoding the input value per the following
convention:
(EQ 5.20)
The output operands can be configured to drive relay outputs, such as remote outputs, direct outputs, contact outputs, or
any combination of these, in order to relay the analog quantity to other UR-series IEDs for further processing.
The digitizer averages the signal prior to digitization for increased accuracy. The extra filtering is in effect only under steady-
state conditions or during slow changes of the input value. When the input signal changes significantly, the filtering is
removed to maintain the response speed of the element.
 DIGITIZER 1

DIGITIZER 1
FUNCTION: Disabled
Range: Disabled, Enabled
MESSAGE
DIGITIZER 1 SOURCE:
Off
Range: Off, any FlexAnalog parameter
MESSAGE
DIGITIZER 1
LIMIT: 1.000 pu
Range: 0.050 to 90.000 pu in steps of 0.001
x
truncated
LIMIT if x LIMIT––
LIMIT if x LIMIT
x otherwise





=
N
out
round
x
truncated
LIMIT
------------------------
127


=
842741A2.CDR
SOURCE
DIGITIZED
VALUE
-LIMIT
LIMIT
FULL SCALE
127
–127
N
out
1–
b
7
2
6
b
6
2
5
b
5
2
4
b
4
2
3
b
3
2
2
b
2
2
1
b
1
2
0
b
0
++++++=