Motor components of the built-in motor and options 3.3 Cooling

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Figure 3-3 Principal dependency of the continuous motor current on the intake temperature of water cooling in the main cooler when the rotor losses are disregarded

Heat-exchanger unit

A heat-exchanger unit must be used to ensure a coolant inlet temperature of 35°C. More than one motor can be operated on a single heat-exchanger unit. The heat-exchanger units are not included in the scope of supply.

The cooling power is calculated from the sum of the power losses of the connected motors. The pump power must be adjusted in accordance with the specified flow and pressure loss of the cooling circuit.

For a list of companies and addresses from whom you can obtain heat-exchanger units, see the appendix.

Dimensioning the heat-exchanger unit

The power loss generated in the motor during continuous operation causes a heat flow, most of which is dissipated via the coolant in the cooling system. A smaller proportion of it is dissipated via the surrounding machine construction. The cooling power of the heat- exchanger unit in the cooling system must be designed in such a way that it can dissipate at least 85 - 90% of the generated power loss. If several motors are operated simultaneously on one cooling system, this value applies to the combined total power loss.

During continuous operation, the motor can only be loaded to the extent that the effective continuous torque Meff does not exceed the rated torque MN. As a result, therefore, the effective power loss cannot exceed the rated power loss PV,N.

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If the actual effective loss is impossible to predict or too complex to calculate, the total combined continuous power loss (table values) of all the motors deployed can be used instead to calculate the required cooling power.

1FW6 Built-in torque motors

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Configuration Manual, 05/2009, 6SN1197-0AD00-0BP7

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Siemens 611 configurationmanual Heat-exchanger unit, Dimensioning the heat-exchanger unit