MegaLife ML-PC10AO-K5NNA1A, Руководство пользователя, Страница: 27 / 30

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--- That there is continuity of earth bonding.
--- That capacitors are discharged: this shall be do-
ne 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;
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:
Repairs to sealed components
During repairs to sealed components, all electrical
supplies shall be disconnected from the equipment
potentially hazardous situation.
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
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 le-
vel 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 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 at-
mospheres. Replacement parts shall be in accord-
ance with the manufacturer’s specifications.
The use of silicon sealant can inhibit the effecti-
veness of some types of leak detection equipm-
ent. Intrinsically safe components do not have to
be isolated prior to working on them.
Note
：
Removal and evacuation
When breaking into the refrigerant circuit to make
repairs – or for any other purpose – conventional
procedures shall be used. However, for flammable
refrigerants it is important that best practice is follo-
detector is not a potential source of ignition and is
suitable for the refrigerant used. Leak detection eq-
uipment shall be set at a percentage of the LFL of the
refrigerant and shall be calibrated to the refrigerant
employed, and the appropriate percentage of gas
(25 % maximum) is confirmed.
Leak detection fluids are suitable for use with most
refrigerants but the use of detergents containing ch-
lorine shall be avoided as the chlorine may react with
the refrigerant and corrode the copper pipe-work.
If a leak is suspected, all naked flames shall be rem-
oved/extinguished.
If a leakage of refrigerant is found which requires br-
azing, all of the refrigerant shall be recovered from
the system, or isolated (by means of shut off valves)
in a part of the system remote from the leak. For ap-
pliances containing flammable refrigerants, oxygen
free nitrogen (OFN) shall then be purged through the
system both before and during the brazing process
.
Cabling
Check that cabling will not be subject to wear, corr-
osion, 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.
Leak detection methods
The following leak detection methods are deemed
acceptable for all refrigerant systems.
Electronic leak detectors may be used to detect re-
frigerant leaks but, in the case of flammable refrige-
rants, the sensitivity may not be adequate, or may
need re-calibration. (Detection equipment shall be
calibrated in a refrigerant-free area.) Ensure that the
Repair to intrinsically safe components
Do not apply any permanent inductive or capacita-
nce loads to the circuit without ensuring that this will
not exceed the permissible voltage and current per-
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 imme-
diately but it is necessary to continue operation,
are constructed of materials which are inherently
resistant to being corroded or are suitably protec-
ted against being so corroded.
Checks to electrical devices
Specialist’s Manual
mitted 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 ign-
ition of refrigerant in the atmosphere from a leak.
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.