Water cooling (1LH1 and 1LN1 motors) Siemens

Обзор



Cooling circuit in the application

When water-cooled motors of the SIMOTICS FD series (1LH1, 1LN1) are operated in the application, they become part of the overall cooling circuit. Apart from the cooling unit, this can include other heat sources.

The construction of the cooling materials demands two completely different cooling concepts for the overall cooling circuit in the application.

For the coolant circuit in SIMOTICS FD motors of the 1LH1 and 1LN1 series, the materials listed in the table "Materials used in the motor (cooling circuit)" can be deployed which provides the user with a range of possibilities for constructing the cooling circuit.

The electrochemical processes that take place in a cooling system must be minimized by choosing the right materials. For this reason, mixed installations, i.e. a combination of different materials, such as copper, brass, iron, zinc, or halogenated plastic (PVC hoses and seals), should not be used or should be limited to the absolutely essential minimum.

Please read the following definitions for clarification:

1. Closed cooling circuit:
The pressure compensator is closed (no ingress of oxygen) and fitted with a pressure-relief valve (6 bar for 1LN1 motors, 3 bar for 1LH1 motors); it is always connected on the suction side of the pump. The coolant is only routed through the SIMOTICS FD motors, the components required for cooling and, if necessary, a converter. The materials used in the cooling circuit comply with the recommendations in the table "Admissible materials for the overall cooling circuit".

2. Semi-open cooling circuit:
Oxygen can only enter the coolant through the pressure compensator, otherwise the cooling circuit corresponds to a closed cooling circuit.

3. Open cooling circuit:
The coolant is guided through the motors and the cooling components required for heat dissipation as well as through components external to the cooling circuit. The materials used comply with the minimum requirements specified in the table "Admissible materials for the overall cooling circuit".

Possible cooling circuits of the SIMOTICS FD motor series

Type

Type of cooling circuit

 

Closed

Semi-open

Open

1LH1

✓

–

–

1LN1

✓

✓

–



For further information on the construction of a cooling circuit, see the Manual "SINAMICS S120 – Chassis Liquid Cooled Power Units".

Cooling water quality

The water-cooled versions of the SIMOTICS FD series offer solutions for different qualities of cooling water. The optimum cooling water quality can therefore be selected in accordance with the location and application. The following tables contain the water properties defined for the various motor versions.

Definition of water properties

  

Water quality

  

Potable water

Fresh water

Sea water

pH value

–

6.5 to 8.0

6.0 to 9.5

6.5 to 10

Carbon-related hardness

mMol/l

–

–

< 0,9

Total hardness

mMol/l

< 2.5

< 1.7

< 1.8

Chloride ions (Cl-)

mg/l

< 50

< 200

< 3000

Sulfate ions (SO42-)

mg/l

< 50

< 240

< 3000

Sulfide ions (S2-)

mg/l

–

–

< 1

Nitrate ions (NO3-)

mg/l

< 50

< 50

< 50

Iron (Fe3+)

mg/l

–

–

< 1

Ferromanganese ions (Fe3+Mn2+)

mg/l

–

–

< 50

Ammoniac (NH3)
Ammonium (NH4+)

mg/l

–

–

< 15

Alkalinity

mg/l

< 300

–

–

Dissolved substances

mg/l

< 340

< 340

< 340

Electrical conductivity

µS/cm

< 500

< 2000

< 32000

Size of entrained particles (sand)

mm

< 0.1

< 0.1

< 0.1

Biological growth

resistant

No

No

Yes



Assignment of motor versions to cooling water quality

Water quality
to motor cooling

Motor type

 

1LH1

1LN1

Potable water

✓

✓

Fresh water

✓ 1)

✓

Sea water

–

✓



Materials used in the motor cooling circuit

Motors of the 1LH1 series are equipped with built-in cooling pipes constructed from copper as standard, or as an option from stainless steel (order code M85).

Motors of the 1LN1 series are equipped with a double-walledair-to-water heat exchanger. The materials used in the 1LH1 and1LN1 series are listed in the table below.

Materials used in the motor (cooling circuit)

Motor type

Materials

1LH1 (standard)

Cu, stainless steel (V2A), CuZn39Pb3

1LN1 (standard)

CuNi (90/10) RILSAN-- plastic-coated steel



Admissible materials for the overall cooling circuit

Material

1LH1

1LH1
with order code M85, 1LN1

Comment

Aluminum

–

✓

 

Zinc

✓

✓

Can be used in closed circuits with inhibitor.

Brass

✓

✓

Can be used in closed circuits with inhibitor.

Copper

✓

✓

Can be used in closed circuits with inhibitor.

Common steel
(e.g. St 37)

✓

✓

Permissible in closed circuits with inhibitors or anti-freeze, check for oxide formation, inspection window recommended.

Cast steel/
cast-iron

✓

✓

Closed circuit and use of strainers and flushback filters.

High-alloy steel, Group 1 (V2A)

✓

✓

 

High-alloy steel, Group 1 (V2A)

✓

✓

 

PVC

–

–

 

Hoses

✓

✓

Reduce use to a minimum.
Must not be used as the main pipe for the whole system.



✓ Admissible
– Inadmissible

Inhibitors, anti-freeze, biocides

Coolant additives

Material

1LH1

1LH1
with order code M85

1LN1

Inhibitor without anti-freeze effect

Required
NALCO
TRAC100

0.2 % < X ≤ 0.25 %

Not required

Not required

Anti-freeze

Antifrogen N
20 % < X ≤ 45 %

Antifrogen L
25 % < X ≤ 48 %

Varidos FSK
25 % < X ≤ 45 %≤ 45 %

Antifrogen N
20 % < X ≤ 45  %

Antifrogen L
25 % < X ≤ 48  %

Varidos FSK
25 % < X ≤ 45 %

Biocide 1)

Yes

Antifrogen N,
minimum quantity 20 %

Antifrogen L,
minimum quantity 30 %

Varidos FSK,
minimum quantity 30 %

Not required

Anti-freeze +
biocide

When Antifrogen N > 20 % or Antifrogen L/
Varidos FSK > 30 % is used, an adequate biocidal effect exists.nden.

 


1) Effectiveness regarding the growth of microorganisms.