GE Multilin 565 Instruction Manual page 58

SETPOINTS MODE - PHASE CURRENT
Location Message Line
S 2.1
SETPOINTS
PHASE CURRENT
Each of the four phase currents are sampled at a rate of approximately 960 samples per second.
S 2.2
PHASE CT RATING
PRIMARY
S 2.3
PHASE TIMED O/C
PICKUP
S 2.4
PHASE O/C CURVE
SHAPE EXTREM INV
Message S 2.5 will not appear if CUSTOM CURVE is selected in message S 2.4.
S 2.5
PHASE O/C
TIME DIAL
S 2.6
PHASE O/C TRIP
RELAY
5-14
Description
The setpoints page 2 header. In this page you must enter information
about the phase current transformers being used in your application. This
allows the 565/575 Relay to accurately sense the feeder currents. This
page also allows you to set the levels for various overcurrent alarms and
trips and assign relays to be activated by these.
Enter the primary current rating of the phase current transformers being
used. This value is found on the transformer nameplate. Values can be
100 A
entered in the range of 10 to 5000 Amps, in steps of 5 Amp. If an attempt
is made to enter a value outside this range an OUT OF RANGE error
message will flash. If your transformer has a rating outside this range
contact MULTILIN for information. Note that all three phase CT's must
have the same rating.
The phase overcurrent pickup level is entered here. This is given as a
percentage of the CT rating, in the range of 25% to 250% in steps of 1%.
100 %CT
This setting will determine the level of current which the 565 Relay will
identify as too high, and then initiate a timed overcurrent trip of the
breaker, according to the selected curve shape.
For example, if 50% is entered here, then the 565/575 Relay will initiate a
timed trip of the feeder breaker when at least one of the phase currents
reaches 50% of the full CT rating entered in message S 2.2. Determine this
value by referring to the feeder design specifications.
The shape of the required protection curve must be entered here. The
curve names are shown below together with the shortened form of the
name which is displayed in this message.
CURVE
NAME
1. Moderately inverse.
2. Normal Inverse.
3. Very Inverse.
4. Extremely Inverse.
5. Custom Curve.
6. IEC
7. IEC
8. IEC
Once the correct curve has been chosen for your application, press the
NEXT CHOICE key until the required curve is displayed in message S 2.4
and store the selected curve using the STORE key. The extremely inverse
curve is shown in this example.
The phase overcurrent time dial number is entered here. This allows the
user to fit the selected curve to the system requirements. Any of the 32
1
possible plots of the selected curve shape may be selected by entering the
corresponding number between 1 and 32 here. Select the curve number
by referring to the "use of standard curves" in section 3.
This message allows the user to select the relay which the phase overcur-
rent trip will activate.
TRIP
DISPLAYED
NAME
MOD INV.
NORMAL INV.
VERY INV.
EXTREM INV.
CUSTOM
IEC A
IEC B
IEC C