Safety precautions
4 Guide for installers 22021223F 17/04
APS768x
1 Safety precautions
The explosion-proof APS768x-230V power supply unit is approved for operation in
Zone 1 and Zone 21 hazardous areas.
The explosion-proof APS768x-120V power supply unit is approved for operation in
hazardous areas of Class I, II, III; Division 1; Groups A–G.
Special care must be taken when using weighing systems with the APS768x power
supply unit in hazardous areas. The code of practice is oriented to the "Safe
Distribution" concept drawn up by METTLER TOLEDO.
Competence ▲ The weighing system may only be installed, maintained and repaired by
authorised METTLER TOLEDO service personnel.
▲ The mains supply may only be installed by a specialist authorised by the owner-
operator.
Ex approval ▲ No modifications may be made to the device and no repair work may be
performed on the modules. Any weighing platforms or system modules that are
used must comply with the specifications. Non-compliant equipment jeopardises
the intrinsic safety of the system, cancels the Ex approval and renders any
warranty or product liability claims null and void.
▲ The safety of the weighing system is only guaranteed when the weighing system
is operated, installed and maintained in accordance with the respective instructions.
▲ Also comply with the following:
– the instructions for the system modules,
– the relevant national regulations and standards,
– the applicable statutory requirements for electrical equipment installed in
hazardous areas in the respective country,
– all instructions related to safety issued by the owner.
▲ The explosion-proof weighing system must be checked to ensure compliance
with the safety requirements before being put into service for the first time,
following any service work and at least every 3 years.
Operation ▲ Prevent the build-up of static electricity. Always wear suitable working clothes
when operating or performing service work in a hazardous area.
▲ Do not use protective covers with the devices.
▲ Prevent damage to the system components.