• That there no live electrical components and wiring are exposed while charging,
recovering or purging the system;
• That there is continuity of earth bonding.
Repairs to sealed components
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 isabsolutely
necessary to have an electrical supply to equipment during servicing, then a permanently
operating form of leak detection shall be located at the most critical point to warn of a
potentially hazardous situation.
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 atmospheres. 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
detection 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.
5. Detection of flammable refrigerants
Under no circumstances shall potential sources of ignition be used in the searching for or
detection of refrigerant leaks. A halide torch (or any other detector using a naked flame)
shall not be used.
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