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4.3.1 Safety Precautions
Before opening the enclosure, it is absolutely necessary to switch off the units located inside
this enclosure and to secure them against powering-up.
For the installation, maintenance and cleaning of the units, it is
absolutely necessary to observe the applicable ordinances and
provisions concerned with explosion protection (VDE 0160, VDE 0165 or
EN 60079-14, EN 50014 – 50039) as well as the Accident Prevention
Regulations (UVV).
4.3.2 Cleaning and Maintenance Work
For the installation, maintenance and cleaning of the units, it is
absolutely necessary to observe the applicable ordinances and
provisions concerned with explosion protection (VDE 0160, VDE 0165 or
EN 60079-14, EN 50014-50039) as well as the Accident Prevention
Regulations (UVV).
Installation, maintenance and cleaning of the units must only be
performed by persons trained and authorized for this purpose, insofar
as they are familiar with the units.
All that might be necessary is to clean the sight glass of the monitoring unit F-351 mounted
externally on the enclosure or the operating unit F-411 which may be connected, if the sight
glass is very dirty. Use only mild soap solutions or similar mild detergents. Maintenance work
on the system and on all components belonging to the system must only be performed by
personnel who are adequately qualified for this task.
4.3.3 Cleaning and Maintenance Intervals
The cleaning intervals depend on how dirty the system is. Please take care to ensure that the
display of the monitoring unit or the operating unit F-411 are always easy to read.
4.3.4 Testing of the Relay Contacts
The facility to open of both relay contacts must be verified by the user in time intervals, which
depend on the danger of the application.
Example:
1. Remove the front cover and switch the supply voltage on.
2. Measure the voltage between the contacts 2 ("L
IN
") and 6 ("N
OUT
"). There must be no
tension.
3. Measure the voltage between the contacts 3 ("N
IN
") and 7 ("L
OUT
"). There must be no
tension.
4. Close the front cover again.
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