ABB ACS880-77CC, Hardware Manual

Page: 120 / 128

Draining the internal cooling circuit
You can drain the internal cooling circuit through the cooling unit as follows:
Note: Draining coolant into the sewer system is not allowed.
WARNING!
High-pressure hot coolant may be present in the internal cooling circuit. No work
on the cooling circuit is allowed until the pressure is lowered down by stopping the
pumps and draining coolant.
1. Lead the bleed hose into a bucket or other suitable container. Extend the standard
hoses when necessary.
2. Open the bleed valve to let air displace the liquid.
3. If required, dry the piping with compressed oil-free air of less than 6 bar (600 kPa).
4. If the converter is to be stored in temperatures below 0 °C (32 °F),
• dry the cooling circuit with air
• fill the cooling circuit with a mixture of water and coolant according to section Freeze
protection and corrosion inhibition (page 122)
• drain the cooling circuit again.
Cooling station control
See manufacturer’s instructions, the circuit diagrams delivered with the converter, and the
firmware manual.
120 Cooling and heating