Maintenance 181
Reduced run
A reduced run function is available for supply and inverter units consisting of parallel-
connected modules. The function makes it possible to continue operation with limited
current even if one (or more) module is out of service, for example, because of
maintenance work.
In principle, reduced run is possible with only one module, but the physical requirements of
operating the motor still apply; for example, the modules remaining in use must be able to
provide the motor with enough magnetizing current.
Starting reduced run operation
WARNING! Repeat the steps described in section Electrical safety
precautions on page 128. The complete safety instructions are given in
Safety instructions for ACS880 multidrive cabinets and modules
(3AUA0000102301 [English]). Ignoring the instructions can cause physical injury or death,
or damage to the equipment.
WARNING! Wear protective gloves and long sleeves! Some parts have sharp
edges.
1. Disconnect the drive from the AC power line and make sure it is safe to start the work.
See section Electrical safety precautions on page 128.
2. If the supply / inverter control unit is powered from the faulty module, connect the
control unit to another 24 V DC power supply. We strongly recommend using an
external power supply with supply / inverter units consisting of parallel-connected
modules.
3. Remove the module to be serviced from its bay.
4. If the STO (Safe torque off) function is in use, install the STO jumper wire set in place
of the missing module (unless the module was the last on the chain).
5. Install an air baffle to the top module guide to block the airflow through the empty
module bay.
6. In case the inverter unit has a DC switch with a charging circuit, disable the
appropriate channel on the charging monitoring unit.
7. Switch on the power to the drive.
8. Enter the number of supply / inverter modules present into parameter 195.13 / 95.13
Reduced run mode.
9. Reset all faults and start the supply / inverter unit. The maximum current is now
automatically limited according to the new configuration. A mismatch between the
number of detected modules (195.14 / 95.14) and the value set in 195.13 / 95.13 will
generate a fault.
10. If the STO function is in use, validate it as described in chapter The Safe torque off
function (page 351).
To Next Page
Loading...
