Metrohm 731 Relay Box - Manual (Page 13)

2.2 Safety information
Relay Box 731, Instructions for use 7
2.2 Safety information
General:
This instrument left our factory in perfect condition from a safety
consideration point of view (see Technical specifications, Safety
specification). To maintain this condition and for danger-free instru-
ment operation the following instructions should be carefully ob-
served.
Line connection:
The line cables supplied with the instrument have three leads and
are fitted with a plug having an earthing pin. If a different plug has to
be used then the yellow/green lead should be connected to earth.
WARNING!
Any break in the earthing lead, whether inside or outside the instru-
ment, represents a potential hazard to the operator. Making a break
in the earthing lead is forbidden.
Before the plug is connected to the line a check must be made to
ensure that the instrument is set to the local line supply voltage and
that the appropriate fuses are inserted.
WARNING!
When exchanging a fuse and when setting a different line voltage
the mains cable must be disconnected from the line supply.
Repair and maintenance:
If errors or malfunctions occur during the operation of the 731 Relay
Box then it is recommended that the cable connections with the pe-
ripheral devices are checked first for proper functioning (see page
15ff).
If it is absolutely necessary to open the instrument then the following
safety measures must be observed at all cost:
The instrument must be separated from all voltage
sources before it is opened. Make sure that the line
connector has been pulled out.
Condensers inside the instrument may still be charged even when
the instrument is no longer connected to the line supply.
Manipulations on an opened instrument that is connected to the line
supply should only be carried out by an expert who is familiar with
the dangers that this involves.