4 3
S V E R K E R 7 5 0 / 7 6 0
P r o g r a m m a E l e c t r i c A B
Z P - C D 0 1 E R 0 5 A
reduce the current by turning the main
knob until resetting takes place. Release
the start switch and make a note of the
current.
Method 3: Time-limited injection
Time-limited injection Time-limited generation, as
its name implies, interrupts output after a preset
time. This is useful when you want to prevent
overheating in the protective relay equipment.
1.
Initial settings: OFF. MAX TIME (see expla-
nation of settings in Chapter 5.) HOLD.
Main knob at 0. The maximum time must
be set longer than the operating time of
the instantaneous unit.
2.
Connect the relay current input and tripping
output to Sverker. 3. Set the ammeter to
measure current at the current output that
is being used.
4.
Set the timer start condition to INT.
5.
Set the timer stop condition (to CLOSURE
+ OPENING, CONTACT for example).
6.
Change the main knob setting.
7.
Activate ON using the start switch. If you
want to check the time, you can activate
ON+TIME instead of ON.
8.
Check to see that the instantaneous unit
has operated. This can be done by a)
checking the indicator lamp on the relay or
b) checking to see that the TRIP indicator
lamp on Sverker is on.
9.
Read the current.
10. Search for the lowest current where the
relay operates, by repeating from point 6
above and onwards.
6.7 Finding pick-up
and drop-out limits for
under (current/
voltage/other entity)
relays
1.
Initial settings: OFF, HOLD, Main knob at 0.
2.
Connect the relay input and tripping output
to Sverker.
3.
Use the button marked A to transfer the
ammeter test point to the current output
that is being used.
4.
Set the timer stop condition (to CLOSURE
+ OPENING, CONTACT for example).
5.
Activate ON using the start switch.
6.
Increase the entity (current or voltage)
being tested until it exceeds by an ample
margin the value of the relay setting.
7.
Turn the main knob anti-clockwise until the
relay trips. Read the pick-up value.
8.
Turn the main knob clockwise until the
relay drops out. Read the drop-out value.
9.
Interrupt output by setting the start switch
to OFF.
Summary of Contents for Programma Sverker 750
Page 1: ...SVERKER 750 760 User s manual Relay Test Unit ...
Page 28: ...2 9 S V E R K E R 7 5 0 7 6 0 P r o g r a m m a E l e c t r i c A B Z P C D 0 1 E R 0 5 A ...
Page 75: ...7 6 S V E R K E R 7 5 0 7 6 0 P r o g r a m m a E l e c t r i c A B Z P C D 0 1 E R 0 5 A ...
Page 76: ...Subject to change without notice Printed matter ZP CD01E R05B 2007 ...
