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MECHANICAL INSTALLATION
Installation guide Powerdrive MD Smart Equipment
5704 en - 2021.10 / b
To ensure the temperature of the above liquid cooling, a 3-way valve or variable speed pump must be installed.
Note:
- The recommended fluid is glycolated water, mix at 25%, the maximum temperature is 40°C.
- Salt water is prohibited.
- We recommend the use of an external cooling loop so that the fluid is used in closed circuit.
- A controlled heating system must be installed to keep the minimum temperature of 5° C inside the enclosure at start-up (to be
disabled when the variable speed drive is in running order).
2.6.3 - Recommendations
• Characteristics of the cooling liquid
:
Since the most stressed components of the drive are completely cooled by liquid, The characteristics of the liquid directly affect
the quality of the cooling and therefore the lifetime of the variable speed drive. Prevent electrochemical corrosion and sediment
obstruction by ensuring that the cooling agent used meets the following criteria:
• pH 7.5 to 8.5
• CaCO3 alkalinity: 100 to 400 mg/l
• chloride Cl-: <200 mg/l
• conductivity: 1000 to 1500 μS/cm
• Liquid temperature increase
:
At steady speed The maximum heating of the coolant at the variable speed drive outlet with the recommended minimum flow is
8°C.
• Protection against electrochemical corrosion:
When an external coolant loop is used, it is recommended to add an inhibitor to prevent electrochemical corrosion. If there is no
external loop, this corrosion shall be avoided by using materials compatible with the materials used in the cooling circuit of the
variable speed drive: question to be asked.
• Protection against sediment obstructions:
A coolant with too many particles can speed up the sediment-induced blockage of radiators, so it is recommended that filters be
installed upstream of the drive fluid system.
• Protection against stopping the circulation of liquid:
To avoid harmful overheating, a liquid circulation monitoring relay must be cabled to the variable speed drive’s safety chain.
2.6.4 - Drainage and maintenance
The frequency of drainage and maintenance cycles depends on the quality of the coolant. These cycles must therefore be
determined based on the quality of the fluid used and designed according to the installation. Temperature elevations caused by
passive components and circuit boards can create condensation on heat sinks or pipe fittings, depending on the humidity in the air
and the temperature difference between the interior of the enclosure and the cooling circuit.
It is therefore advisable to have a coolant temperature as close as possible to the internal temperature of the enclosure, depending
on the use of the variable speed drive. This can be achieved by reducing the ambient temperature or increasing the temperature of
the fluid (respect the maximum temperatures described in section 3.5.2).
3-way valve
View from behind
