NORD Drivesystems BU0220 - Manual (Page 12)

PROFIBUS DP – Supplementary manualfor NORD Frequency Inverter SK 2xxE
12 Subject to technical amendments BU 0220 GB-0912
1.6 Version with protection class IP55 / IP66
The SK 2xxE frequency inverter and the external additional modules are available with protection classes
IP55 (Standard) or IP66 (optional) and in all sizes and power ratings.
The protection class IP66 must always be stated when ordering!
There are no restrictions or differences to the scope of functions in either protection class. In order to
differentiate the protection classes, modules with protection class IP66 are given an extra "-C" (coated 
coated PCBs) in their type designation.
e.g. SK TU4-PBR-C
IP55 version:
The IP55 version of the external technology units is the standard version. Both versions (inverter-mounted –
as a supplement to the frequency inverter or wall mounted on the wall bracket) are available.
IP66 version:
In contrast to the IP55 version the IP66 version is a modified option. With this design, both versions
(inverter-mounted or wall-mounted) are also available. The modules available for the IP66 version (adapter
units, technology units and customer units) have the same functionalities as the corresponding modules for
the IP55 version.
NOTE
The modules for the IP66 design are identified by an additional "-C" and are modified
according to the following special measures!
Special measures:
Impregnated PCBs, coated housing
Diaphragm valve for pressure compensation on temperature changes.
Low pressure test
 A free M12 screw connection is required for low pressure testing. After successful testing, a
diaphragm valve is inserted here. This screw connection is therefore no longer available for
a cable gland.
NOTE
For all versions, care must be taken that the cable and the cable gland are carefully
matched. This is essential to ensure that the required protection class is maintained.