UFESA PAC Alaska 7, Instruction Manual, Page: 62 / 200

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unless the components are constructed of materials which are inherently resistant or
suitably protected against being corroded.
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
adequate temporary solution shall be used. This shall be reported to the owner of the
equipment 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 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
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
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
components, the casing is not altered in such a way that the level of protection is affec -
ted. 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.
Repair to intrinsically safe components
Do not apply any permanent inductive or capacitance loads to the circuit without en-
suring 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 re -
sult in the ignition of refrigerant in the atmosphere from a leak.
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 ageing or continual vibration from sources such as compressors
or fans.