Safety Instructions - ABB DCT880 Service Manual

Safety Instructions

Chapter overview
This chapter contains the safety instructions you must follow when installing, operating and servicing the
thyristor power controller. If ignored, physical injury or death may follow, or damage may occur to the thyristor
power controller or the connected equipment. Read the safety instructions before you work on the unit.
To which products this chapter applies
The information is valid for the whole range of the product DCT880.
Usage of warnings and notes
There are two types of safety instructions throughout this manual: warnings and notes. Warnings caution you
about conditions, which can result in serious injury or death and/or damage to the equipment, and advice on
how to avoid the danger. Notes draw attention to a particular condition or fact, or give information on a
subject. The warning symbols are used as follows:
Dangerous voltage warning warns of high voltage, which can cause physical injury or death
and/or damage to the equipment.
General danger warning warns about conditions, other than those caused by electricity, which
can result in physical injury or death and/or damage to the equipment.
Electrostatic sensitive devices warning warns of electrostatic discharge, which can damage
the equipment.
Installation and maintenance work
These warnings are intended for all who work on the thyristor power controller, the cables or the connected
equipment. Ignoring the instructions can cause physical injury or death and/or damage to the equipment.
WARNING!
Only qualified electricians are allowed to install and maintain the thyristor power
controller!
− Never work on the thyristor power controller, the cables or the connected equipment when
main power is applied. Always ensure by measuring with a multimeter (impedance at least
1 Mohm) that:
1. Voltage between thyristor power controller input phases U1, V1, W1 and the frame is
2. Voltage between thyristor power controller output phases U2, V2, W2 and the frame is
− Do not work on the control cables when power is applied to the thyristor power controller or
to the external control circuits. Externally supplied control circuits may cause dangerous
voltages inside the thyristor power controller even when the main power on the thyristor
power controller is switched off.
− Do not make any insulation resistance or voltage withstand tests on the thyristor power
controller.
− Isolate the cables to the equipment from the thyristor power controller when testing the
insulation resistance or voltage withstand of the cables or the equipment.
− When reconnecting the cables to the equipment, always check that the U2, V2 and W2
cables are connected with the proper terminal.
Notes:
− The output phase cable terminals on the thyristor power controller are at a dangerously high
voltage when the main power is on.
− Depending on the external wiring, dangerous voltages (115 V, 220 V or 230 V) may be
present on the relay outputs of the thyristor power controller (e.g. XRO1 ... XRO3).
− DCT880 with enclosure extension: Before working on the thyristor power controller, isolate
the whole thyristor power controller system from the supply.
close to 0 V.
close to 0 V.
3ADW000449R0101 DCT880 Service Manual e a
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Safety Instructions