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During repairs to sealed components, all electrical supplies must be
disconnected from the equipment being worked upon prior to any
removal of sealed covers, etc.
If it is absolutely necessary to have an electrical supply to
equipment during servicing, then a permanently operating form of
leak detection must be located at the most critical point to warn of a
potentially hazardous situation.
Particular attention must be paid to the following to ensure that by
working on electrical components, the casing is not altered in such a
way that the level of protection is affected. This must include
damage to cables, excessive number of connections, terminals not
made to original specification, damage to seals, incorrect fitting of
glands, etc.
Ensure that the apparatus is mounted securely.
Ensure that seals or sealing materials have not degraded to such an
extent that they no longer serve the purpose of preventing the
ingress of flammable atmospheres. Replacement parts must be in
accordance with the manufacturer’s specifications.
NOTE: The use of silicon sealant may inhibit the effectiveness of
some types of leak detection equipment. Intrinsically safe
components do not have to be isolated prior to working on them.
11.Repair to intrinsically safe components
Do not apply any permanent inductive or capacitance loads to the
circuit without ensuring that this will not exceed the permissible
voltage and current permitted for the equipment in use.
Intrinsically components are the only types that can be worked on
while live in the presence of a flammable atmosphere. The test
apparatus must be at the correct rating.
Replace components only with parts specified by manufacturer.
Other parts may result in the ignition of refrigerant in the
atmosphere from a leak.
12.Cabling
Check that the cabling will not be subject to wear, corrosion,
excessive pressure, vibration, sharp edges or any other adverse
environmental effects. The check must also take into account the
effects of aging or continual vibration from sources such as
compressors or fans.
13.Leakage detection for flammable refrigerants