Thermal Overload Protection, Two Time Constants Trpttr (49) - ABB RET670 Commissioning Manual

1MRK 504 154-UUS B
10.5.8

Thermal overload protection, two time constants TRPTTR (49)

Prepare the IED for verification of settings as outlined in section
section "Preparing for test"
10.5.8.1 Checking trip and reset values
1. Connect symmetrical three-phase currents to the appropriate current terminals of the IED.
2. Set the Time constant 1 (
3. Set the three-phase injection currents slightly lower than the set trip value of stage
increase the current in phase A until stage
4. Decrease the current slowly and note the reset value.
Check, in the same way, the trip and reset values of
5. Activate the cooling input signal, thus switching to base current
6. Check the trip and reset values (for all three phases) for
above for stage
7. Deactivate the input signal for stage
8. Set the time constant for
9. Set the injection current for phase A to 1.50 ·
10. Connect a trip output contact to the timer and monitor the output of contacts ALARM1 and
ALARM2 to digital inputs in test equipment.
Read the heat content in the thermal protection from the local HMI and wait until the content
is zero.
11. Switch on the injection current and check that ALARM1 and ALARM2 contacts trip at the set
percentage level and that the trip time for tripping is in accordance with the set Time
Constant 1 (
With setting Itr = 101%
content in the memory shall be 0.60 · Time Constant 1 (
12. Check that all trip and alarm contacts trip according to the configuration logic.
13. Switch off the injection current and check from the service menu readings of thermal status
and LOCKOUT that the lockout resets at the set percentage of heat content.
14. Activate the cooling input signal to switch over to base current
Wait 5 minutes to empty the thermal memory and set Time Constant 2 (
with the setting plan.
15. Test with injection current 1.50 ·
the lockout reset in the same way as described for stage
16. Finally check that pickup and trip information is stored in the event menu.
10.5.8.2 Completing the test
Continue to test another function or end the test by changing the
Restore connections and settings to their original values, if they were changed for testing
purposes.
Commissioning manual
in this chapter.
Tau1 ) and Time Constant 2 ( Tau2 ) temporarily to 1 minute.
Observe the maximum permitted overloading of the current circuits in the
IED.
IBase1 .
IBase1 in accordance with the setting plan.
Tau1 ).
IBase1 and injection current 1.50 · IBase1 , the trip time from zero
IBase2 the thermal alarm level, the trip time for tripping and
"Requirements"
IBase1 trips and note the trip value.
IBase1 for phases B and C.
IBase2 in the same way as described
IBase2 .
IBase1 .
Tau1 ).
IBase1 .
TestMode setting to Disabled .
Testing functionality by secondary injection
and
IBase1 ,
IBase2 .
IBase2 .
Tau2 ) in accordance
Section 10
SEMOD53632-3 v5
SEMOD53632-11 v7
SEMOD53632-51 v5
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