ABB PSTX 1050, Руководство по обслуживанию

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1SFC13105M0201 | Service Manual | Service PSTX720...840 51
4. Switch Megger cables
Switch the connection according to figure 4:
1
Connect the red megger contact to the main
terminal 1L1 on the Softstarter.
2
Connect the black megger contact to the main
terminal 2T1 on the Softstarter.
3
Set the megger on 500V. Press and hold the
Test button. Note the result.
Repeat step
5. Connect the Megger to the Softstarter
and
6. Switch the Megger cables
on the two remaining phases between
3L2 - 4T2 and 5L3 - 6T3.
5. Detect a shorted SCR
The three different phases will give six values.
If any of the values shows lower than 1 Mohm there
is probably a shortage. Proceed with changing the
SCR, see chapter
3.7.1 Change the SCR .
6. Connect SCR cables to PCBA
When reconnecting cables; read markings on the
PCBA bracket.
1
Thread all three SCR cables through the cable
inlets on the PCBA bracket.
2
Connect the three SCR cables, according
to previously made markings (1, 2 or 3), to their
terminals on the PCBA.
7. Place HMI cover
1
Place back the PCBA and the bracket in the
Softstarter. Make sure cables do not get stuck in
between the bracket frame and Softstarter when
mounted.
Place the HMI cover on the unit and align it to the
plastic screw sleeves located on lower housing.
2
Fasten the HMI cover with (4x) Torx 20
M4x12 (1,6Nm)
.
3
Fasten (1x) Torx 15 M3,5x12 (0,5 Nm)
on the HMI bracket.
REASSEMBLE THE SOFTSTARTER
Connect main power cables and control
cables
Connect the main power cables and the control
cables as described in
chapter 3.3.4, step 1-2
.
8. Examples of SCR for PSTX
For Softstarters type PSTX720...840 we are using
SCR:s of capsule types.
See figure 8 .
Please note that this type of SCR has to be
correctly mounted when tested to get the correct
result.
1000V
500V
M
OFF 250V
M
1000V
500V
M
OFF
250V
4
3.8.1_4
3
2
1
6
3.8.1_6
1
2
Tx 20 (1,6 Nm)
M4 x 12
Tx 15 (0,5 Nm)
M3,5 x 12
7
3.8.1_7
1
2
3
8
3.8.1_8
3