24
Initial safety checks shall include:
•
That capacitors are discharged: this shall be done in a safe manner to avoid possibility of spar-
king;
•
That no live electrical components and wiring are exposed while charging, recovering or pur-
ging the system;
•
That there is continuity of earth bonding.
Repairs to sealed components
During repairs to sealed components, all electrical supplies shall be disconnected from the equip-
ment 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 shall be located at the most critical point to warn of a potentially hazardous
situation.
Particular attention shall be paid to the following to ensure that by working on electrical com-
ponents, 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 speci-
fication, 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 the point 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.
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.
NOTE : The use of silicon sealant can inhibit the effectiveness of some types of leak detection
equipment. Intrinsically safe components do not have to be isolated prior to working on them.
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.
Detection of flammable refrigerants
Under no circumstances shall potential sources of ignition be used in the searching for or detec-
tion of refrigerant leaks. A halide torch (or any other detector using a naked flame) shall not be
used.
To Next Page
Loading...
Need help?
General
