ABB ACS880-77CC, Hardware Manual

Page: 21 / 128

Work on the liquid cooling system
These instructions are intended for all who are responsible for installation and maintenance
work of the liquid cooling system of the converter.
WARNING!
Obey these instructions. If you ignore them, injury or damage to the equipment
can occur.
• Use protective eyewear when working with the liquid cooling system.
• Beware of hot liquid. Do not work on the liquid cooling system until the pressure
is lowered down by stopping the pumps. High-pressure hot coolant (600 kPa,
over 50 °C/122 °F) is present in the internal cooling circuit when the converter
is in operation.
• Before power switch-on, make sure that the internal cooling circuit is filled up
with coolant. Running the external cooling pump dry will damage it. Also the
converter will not cool down.
• Avoid skin contact with coolant, especially antifreeze. Do not syphon them by
mouth. If such substance is swallowed or gets into the eyes, seek medical
advice.
• To avoid breaking the coolant pipes, do not overtighten the nuts of the unions.
• Blue connectors: Leave 2…3 millimeters (0.08 … 0.12 inches) of thread
visible.
2...3 mm
• Black connectors: Tightening torque is 10 N·m (7.4 lbf·ft) in room
temperature (20 °C/68 °F).
• If the ambient temperature is below +5 °C (41 °F), add antifreeze and corrosion
inhibitors to the cooling liquid.
• Drain the system before storing in temperatures below 0 °C (32 °F). Freezing
of the liquid cooling system is not allowed. Operation at liquid temperatures
below zero is not permitted, not even with antifreeze.
Safety instructions 21