Installation Of Water-Cooled Units; Heat Sink And Operating Pressure; Materials In The Cooling Cicuit - KEB COMBIVERT F5 Instruction Manual

General
1.5

Installation of water-cooled units

In continuous operation water-cooled inverters are operated with lower temperature than air-cooled inverters. This
has positive effects on lifetime-relevant components such as fan and DC link circuit capacitors and power mo-
dules (IGBT). Also the temperature dependent switching losses are positively effected. The use of water-cooled
KEB COMBIVERT frequency inverters is offered in the drive technology, because there are process-caused
coolants available with some applications. The following instructions must be observed absolutely when this units
are used.

1.5.1 Heat sink and operating pressure

Design system
Extrusion casting heat sink
The heat sinks are sealed with sealing rings and have also a surface protection (anodized) in the ducts. The heat
sinks are generally maintenance-free!
In order to avoid a deformation of the heat sink and the damages involved, the indicated max. opera-
ting pressure may not be exceeded briefly also by pressure peaks.
Pay attention to the guidelines 97/23/EG of pressure units.

1.5.2 Materials in the cooling cicuit

For the screw connections and also for the metallic articles in the cooling circuit which are in contact with the
coolant (electrolyte) a material is to be selected, which forms a small voltage difference to the heat sink in order
to avoid contact corrosion and/or pitting corrosion (electro-chemical voltage series, see table 1.5.2). An aluminum
screw connection or ZnNi coated steel screw connection is recommended. Other materials must be examined in
each case before employment. The specific case of application must be checked by the customer in tuning of the
complete cooling circuit and must be classified according to the used materials. With hoses and seals take care
that halogen-free materials are used.
A liability for occuring damages in case of wrong used materials and from this resulting corrosion cannot be as-
sumed!
Table 1.5.2
Material
Lithium
Potassium
Calcium
Sodium
Magnesium
Titan
Aluminium
Manganese
Zinc
Chrome
Iron
Cadmium
GB - 8
Material (voltage)
Aluminium (-1.67 V)
Electro-chemical voltage series / standard potentials against hydrogen
generated Ion Standard poten-
Li
+
K
+
Ca
2+
Na
+
Mg
2+
Ti
2+
Al
3+
Mn
2+
Zn
2+
Cr
3+
Fe
2+
Cd
2+
Max. operating pressure
Material
tial
-3.04 V Cobald
-2.93 V Nickel
-2.87 V Tin
-2.71 V Lead
Iron
-2.38 V
-1.75 V Hydrogen
-1.67 V Copper
-1.05 V Carbon
-0.76 V Silver
-0.71 V Platinum
-0.44 V Gold
-0.40 V Gold
Connecting duct
10 bar 00.00.650-G140
generated Ion
Co
2+
Ni
2+
Sn
2+
Pb
3+
Fe
3+
2H
+
Cu
2+
C
2+
Ag
+
Pt
2+
Au
3+
Au
+
Standard poten-
tial
-0.28 V
-0.25 V
-0.14 V
-0.13 V
-0.037 V
0.00 V
0.34 V
0.74 V
0.80 V
1.20 V
1.42 V
1.69 V