1.9 Checks to electrical devices
Repair and maintenance to electrical components shall include initial safety checks and
component inspection procedures. If a fault exists that could compromise safety, then no
electrical supply shall be connected to the circuit until it is satisfactorily dealt with. If the
fault cannot be corrected immediately but it is necessary to continue operation, an ade-
quate temporary solution shall be used. This shall be reported to the owner of the equip-
ment so all parties are advised.
Initial safety checks shall include: that capacitors are discharged: this shall be done in a
safe manner to avoid possibility of sparking; that there no live electrical components and
wiring are exposed while charging, recovering or purging the system; that there is continui-
ty of earth bonding.
2 REPAIRS TO SEALED COMPONENTS
2.1 During repairs to sealed components, all electrical supplies shall be disconnected from
the equipment being worked upon prior to any removal of sealed covers, etc. If it is abso-
lutely necessary to have an electrical supply to equipment during servicing, then a perma-
nently operating form of leak detection shall be located at the most critical point to warn of
a potentially hazardous situation.
2.2 Particular attention shall 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 shall include damage to cables, excessive number of connections, terminals not
made to original specification, damage to seals, incorrect fitting of glands, etc. Ensure that
apparatus is mounted securely. Ensure that seals or sealing materials have not degraded
such that they no longer serve the purpose of preventing the ingress of flammable atmos-
pheres. Replacement parts shall be in accordance with the manufacturer's specifications.
NOTE The use of silicon sealant may inhibit the effectiveness of some types of leak detec-
tion equipment. Intrinsically safe components do not have to be isolated prior to working
on them.
3 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 safe components are the only types that can be worked on while live in the
presence of a flammable atmosphere. The test apparatus shall be at the correct rating.
Replace components only with parts specified by the manufacturer. Other parts may result
in the ignition of refrigerant in the atmosphere from a leak.
4 CABLING
Check that cabling will not be subject to wear, corrosion, excessive pressure, vibration,
sharp edges or any other adverse environmental effects. The check shall also take into
account the effects of aging or continual vibration from sources such as compressors or
fans.
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