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ENGLISH
(Original instructions)
CHECKS TO ELECTRICAL DEVICES
- Repair and maintenance to electrical compo-
nents 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 capac-
itors 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.
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 absolute-
ly 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.
- Particular attention shall be paid to the fol-
lowing 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, exces-
sive 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 flamma-
ble 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 detec-
tion equipment. Intrinsically safe components
do not have to be isolated prior to working on
them.
10
REPAIR TO INTRINSICALLY SAFE COMPO-
NENTS
- Do not apply any permanent inductive or ca-
pacitance loads to the circuit without ensuring
that this will not exceed the permissible volt-
age 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.
CABLING
- Check that cabling will not be subject to wear,
corrosion, excessive pressure, vibration,
sharp edges or any other adverse environ-
mental 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 REFRIGE-
RANTS
- Under no circumstances shall potential sourc-
es 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.
LEAK DETECTION METHODS
- The following leak detection methods are
deemed acceptable for systems contain-
ing flammable refrigerants. Electronic leak
detectors shall be used to detect flammable
refrigerants, but the sensitivity may not be ad-
equate, or may need recalibration. (Detection
equipment shall be calibrated in a refrigerant-
free area.) Ensure that the detector is not a
potential source of ignition and is suitable for
the refrigerant used. Leak detection equip-
ment shall be set at a percentage of the LFL
of the refrigerant and shall be calibrated to the
refrigerant employed and the appropriate per-
centage of gas (25 % maximum) is confirmed.
Leak detection fluids are suitable for use with
most refrigerants but the use of detergents
containing chlorine shall be avoided as the
chlorine may react with the refrigerant and
corrode the copper pipework. If a leak is sus-
pected, all naked flames shall be removed/ex-
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