Siemens 6SE7086-4AH85-1BA0 Use, Coolant, Definition of cooling water, Bar, Anti-freeze additive

01.03 Assembly

2.2Use

The same general conditions apply to use as for air-cooled units, with the exception of the cooling conditions already mentioned.

Water is normally used as the cooling medium. Only in special cases should antifreeze be added. In the cooling-water temperature range of +5 to +38 °C, operation with 100 % of the rated current is possible.

2.3Coolant

Normal service water or a mixture of water and antifreeze can be used as the coolant.

2.3.1Definition of cooling water

Chemically neutral and clean water containing no solid bodies (municipal water supply).

Max. particle size of any particles contained	< 0.1mm
pH value	6.0 to 8.0
Chlorides	< 40 ppm
Sulphates	< 50 ppm
Dissolved substances	< 340 ppm
Overall hardness	< 170 ppm
Conductivity (only water, see Section 2.3.2)	< 500 µS/cm
Cooling-water temperature increase per unit (rated operation)	∆ T N 5°C
Operating pressure	< 2.5 bar

Caution! Operating pressure higher than 2.5 bar is not permissible.

Heat-sink material: not resistant to sea water (i.e. it must not be cooled directly with sea water)!

The instructions given regarding the quality of the coolant (diameter of suspended particles < 0.1 mm) must be complied with as accurately as possible. Otherwise, there is a danger that the fine cooling conduits will be blocked!

If the system is to be operated with a higher pressure, the admission pressure at each unit is to be reduced to 2.5 bar.

In the unit's cooling-water circuit, filters (sieves) for a particle size of < 100 µm are to be used! Filters (sieves) are to be cleaned at regular intervals.

If there is a danger of frost, frost-protection measures are necessary for operation, storage and transport, e.g. emptying and blowing out with air, additional heaters etc.

2.3.2Anti-freeze additive

Due to their physical properties (thermal capacity, thermal conductivity, viscosity), anti-freeze agents reduce the performance of the cooling system. They should only be used, therefore, if it is unavoidable.

If you use anti-freeze agents, make sure that you comply with the reduction curve shown in the section, "Technical data". If this is not done, the unit's overtemperature protection device can be triggered. Premature ageing of the unit's components can also occur.

NOTE:

It must always be ensured that the necessary pump output is adapted to the viscosity increase when anti-freeze is added. The back-pressure occurring in the unit must also be taken into account.

Siemens AG 6SE7086-4AH85-1BA0	ENGLISH	2-3
Common rectifier and rectifier/regenerating units with water cooling	Supplement to the operating instructions