Manta MTS-1700 SERIES, Руководство по эксплуатации и справочник

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OPERATION SUMMARY - Section 3
3-12 MTS-1700 SERIES OPERATION AND REFERENCE MANUAL
MANTA TEST SYSTEMS
CU A002 15A
3.3.5.2 MINIMUM PICKUP TEST
.
To check the minimum pickup level of an overcurrent relay:
1. If the MTS-1720 is on and connected, then turn it off.
2. Make test connections, as shown in Figure 3.4.
3. Press [STATIC/DYNAMIC], as required, to select STATIC operation mode.
4. Press and hold [FAULT], or short the [EXTERNAL START] contact inputs. This holds the MTS-1710
in the fault state, indicated by the illuminated [FAULT] button.
5. Press [CURRENT] to display/adjust current.
6. Turn the [MODIFY] knob to slowly increase the current. When the relay contacts close, the [TONE]
button will light. If the audible stop trigger tone has been enabled (by pressing the [TONE] button), the
tone also will sound. The current may be adjusted as required to determine the minimum pickup level.
7. Release the [FAULT] button and remove connections to the [EXTERNAL START] inputs.
Note: A foot switch is often useful when doing this type of work. Connect a normally open foot switch to
the [EXTERNAL START] contact inputs, and press on the switch to apply fault voltage and
current levels. Release to return to prefault (or off) levels.
3.3.5.3 INVERSE-TIME CHARACTERISTIC TEST.
To check the inverse-time curve of an overcurrent relay:
1. Make test connections, as shown in Figure 3.4.
2. Press [STATIC/DYNAMIC], as required, to select STATIC operation mode.
3. Press and hold [FAULT] or short the [EXTERNAL START] contact inputs. This holds the MTS-1710
in the fault state, indicated by the illuminated [FAULT] button.
4. Press [CURRENT] to display/adjust the current. Turn the [MODIFY] knob to set the test current.
5. Release the [FAULT] button and remove connections to the [EXTERNAL START] inputs.
6. Press [STATIC/DYNAMIC] to select DYNAMIC operation mode.
7. Press [FAULT] to initiate timing check.
8. When the relay operates, the [STOP/RESET] button will illuminate. The operate time and current can
be viewed by pressing [TIME] and [CURRENT] respectively. Press [STOP/RESET] to return to the
prefault state and prepare for the next test.
9. For each new value of current, repeat steps 2 to 9.
3.3.5.4 INSTANTANEOUS ELEMENT TEST.
To check the instantaneous element of an overcurrent relay:
1. Make test connections, as shown in Figure 3.4. Note that, on some relays, the instantaneous element may
have a separate set of contacts. Select I1-HIGH current mode if more than 30A is required. Otherwise,
select I1- LOW current mode.
2. Press [STATIC/DYNAMIC], as required, to select STATIC operation mode.
3. Press [CURRENT] to display current.