Текст страницы
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 there no live
electrical components and wiring are exposed while charging, recovering or
purging the system; that there is continuity 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 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.
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 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.