ABB RET670 - Estimation of Transformer Insulation Life LOLSPTR (26;49 HS); Verifying the Signals and Settings

11.13.6 Estimation of transformer insulation life LOLSPTR (26/49HS)
Prepare the IED for verification of settings outlined in Section
"Preparing the IED to
verify settings".
11.13.6.1 Verifying the signals and settings
Time measurement and the injection of current and voltage can be done using common
test equipment.
Verifying HPTMPMAX and TOTCALC outputs
1. Connect the test set for injection of three-phase currents to the appropriate current
terminals of the IED.
2. Activate the TOTVALID input and set some temperature value in TOTEMP input.
3. Supply the IED with three-phase currents slightly more than the rated value.
4. Make sure that the hot spot temperature (HPTMPMAX) is more than the set value
of TOTEMP.
5. Activate the AMBVALID input and set some temperature value in AMBTEMP
input.
6. Make sure that the top oil temperature calculated (TOTCALC) is more than the set
value of AMBTEMP.
Verifying WARNINGx and ALARMx outputs
1. Connect the test set for injection of three-phase currents to the appropriate current
terminals of the IED.
2. Make sure that the settings in the IED are appropriate, especially the warning
temperature levels (WrnHPTmpLevX) and alarm time settings (tDelayToAlarmX).
3. Supply three-phase currents nearly zero to the IED and take note of hot spot
temperature (HPTMPMAX).
4. Make sure that the WARNINGx and ALARMx signals remains low.
5. Supply three-phase currents slightly more than the rated value to the IED and take
note of hot spot temperature (HPTMPMAX).
Observe the maximum permitted overloading of the current circuits in the IED.
6. Check the time until the warning limit has reached WrnHPTmpLev1 level during
injection. Monitor the signal WARNING1 until it appears on the corresponding
binary output.
7. Compare the measured temperature (HPTMPMAX) with WrnHPTmpLev1 setting.
8. check the time until the warning limit has reached WrnHPTmpLev2 level during
injection. Monitor the signal WARNING2 until it appears on the corresponding
binary output.
9. Compare the measured temperature (HPTMPMAX) with WrnHPTmpLev2 setting.
1MRK 504 165-UUS - Section 11
Testing functionality by secondary injection
Transformer protection RET670 2.2 ANSI 279
Commissioning manual