8WE2108
HBM A1632-2.0 en
•An extra low voltage (10 − 35 V) with safe isolation from the mains is
required for the power supply of the unit.
•When connecting additional devices, the safety regulations according to
EN610101) must be complied with.
•Observe the maximum voltage level when connecting external control sys-
tems to the process input and process outputs of the WE2108.
•The ground connections of the supply, of the process inputs and process
outputs, of the interface and the shield of the load cell cable are connected
with one another in the unit. In the case of potential differences of the
devices to be connected, isolate the signals in a suitable manner (e.g. by
optocoupler).
•Shielded cables are required for all connections, except for power supply.
The shield must be connected flatly with ground at both ends.
•The use of unscreened voltage supply cables is permissible only for cables
with a length of up to 30 m max., which are laid within a building. In the
case of greater cable lengths, or installation outside buildings, a screened
cable must be used. In order to compensate for potential differences, the
metal housing of WE2108M / WE2108S has to be connected via a low
ohmic compensation conductor with the scale components as well as with
the ground potential of the connected units. This is not necessary if a poten-
tial difference of 35 V is not exceeded.
In the unit, the reference ground (GND) for all signals and the supply volt-
age is connected directly to the cable screen connection, but not to the
housing.
•The front foil is manufactured from high quality materials and offers a ser-
vice life appropriate for the external conditions. The keys may be operated
only by hand, under no circumstances may pointed objects be used to
press the keys.
!) ”Safety regulations for electrical measuring, control and laboratory equipment“
Residual dangers
The scope of supply and performance of the scale electronic unit covers only
a small area of weighing technology. In addition, equipment planners, install-
ers and operators should plan, implement and respond to the safety engineer-
ing considerations of weighing technology in such a way as to minimise resid-
ual dangers. Prevailing regulations must be complied with at all times. There
must be reference to the residual dangers connected with weighing technol-
ogy.
