Siemens SINAMICS GM150, Инструкции по эксплуатации и монтажу

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3.5.12 Re-cooling unit
3.5.12.1 Re-cooling unit requirements
The re-cooling unit must comply with the following requirements:
● The raw water to be supplied by the plant flows through the heat exchanger that cools the
deionized water. To limit the volume of the deionized water, a re-cooling unit with a dual-
circuit system is required. Limit the deionized water circuit to the re-cooling unit and the
drive.
● The design of the re-cooling unit is part of the system integration. This affects, in particular,
deviations from the required environmental conditions, such as aggressive cooling water.
Use heat exchanger plates made of titanium for aggressive cooling water, such as sea
water or high chloride content. If necessary, also consider an increased corrosion for the
design.
● In the variant as water-air re-cooling unit, the heat loss is dissipated to the ambient air using
a separate installed heat exchanger. If you expect air temperatures below 0° C, you must
install a water-glycol intermediate circuit. Glycol is not permitted in the ionized-water circuit.
The measuring units and the control of the electrical equipment are evaluated in the re-
cooling unit. The supplier calibrates the measuring units in accordance with the order
specifications.
● Any failure of the re-cooling unit causes the immediate shutdown of the drive. If the re-
cooling unit is provided by the system integrator, take this into consideration for the
configuring.
● Use two redundant circulating pumps. No interruption of the flow is permitted. The only
exception is a pump shutdown. The shutdown time must not exceed three seconds.
● Provide an overpressure valve in the raw water discharge of the heat exchanger. To keep
the temperature of the ionized water constant within specified limits and to prevent
condensation, on request, a control valve (tree-way valve) can be installed as bypass.
Because the valve is controlled depending on the temperature of the deionized water, up
to approx. 100% of the raw water can be conveyed past the heat exchanger.
● Acquire the temperature of the raw water with a sensor and evaluate the data.
● To reduce the raw water consumption, the flow quantity can be reduced. A reduction,
however, is possible only when the raw water does not contain any suspended matter that
could accumulate in the heat exchanger for a slower flow speed.
● Procure timely any consumables and spare parts from the supplier of the re-cooling unit.
3.5.12.2 Operating principle of the re-cooling unit
The re-cooling unit dissipates the heat loss from the drive. The deionized water in the internal
water circuit absorbs the heat of the drive power unit which is to be dissipated, and is pumped
to the heat exchanger by a maintenance-free circulating pump. The warm deionized water is
cooled by the external raw water circuit and pumped back to the drive.
Two pipes are installed in the drive. The cold water of the re-cooling unit flows in one of the
pipes, and is heated by the losses and flows back to the re-cooling unit through the other pipe.
Description
3.5 Description of the components
SINAMICS GM150 6SL3815-2LN41-4AA2
52
Operating Instructions 04/2017