Heinrichs Messtechnik GmbH
TM/TMU/TM-SH Supplement Manual
For Explosion Flow-meters
Page 15 of 20
5.
Maintenance and repair work
5.1
Definition of terms according to IEC 60079-17:
Maintenance: defines a combination of any actions carried out to retain an item in, or restore it to, conditions in
which it is able to meet the requirements of the relevant specification and perform its required functions.
Inspection: defines any action comprising careful scrutiny of an item carried out either without dismantling, or
with the addition of partial dismantling as required, supplemented by means such as measurement, in order to
arrive at reliable conclusion as to the condition of an item.
Visual inspection: defines an inspection which identifies, without the use of access equipment and tools, those
defects, such as missing bolts, which will be apparent to the eye.
Close inspection: defines an inspection which encompasses those aspects covered by a visual inspection and, in
addition, identifies those defects, such as loose bolts, which will be apparent only be the use of access
equipment, for example steps, where necessary, and tools.
Detailed inspection: defines an inspection which encompasses those aspects covered by a close inspection and,
in addition, identifies those defects, such as loose terminations, which will only be apparent by opening the
enclosure, and/or using, where necessary, tools and test equipment.
a)
Maintenance or replacement work must be carried out by qualified personnel only, i.e. personnel
qualified according to TRBS 1203 or similar.
b)
Only auxiliary components which comply with all North American requirements, national directives and
legislations may be used in potentially explosive atmospheres
c)
At the presence of Ex-atmospheres, the equipment must be regularly cleaned. The intervals are to be
defined by the operator in compliance with the environmental rules valid at the place of operation.
d)
After maintenance and repair works have been performed, all barriers and notices removed for that
purpose must be returned to their original place.
e)
In the event that faults of the equipment are detected, the equipment is to be removed. The internal
components cannot be maintained by the customer. The equipment is to be returned to the
manufacturer for inspection.
f)
Fuses, with the exception of the replaceable mains fuse, may not be replaced by the operator, since
affected zener-diodes must also be simultaneously replaced. This work requires a follow-up
adjustment, which can only be carried out at the manufacturer’s factory.
Activity
Visual inspection
Close inspection Detailed inspection
3 month interval
6 month interval
12 month interval
1
Visual inspection of equipment for
intactness, removal of dust settlements
X
2
Check of electrical system for intactness
and functionality
X
3 Check of entire system
User's responsibility
