CLIVET WSAN-YMi 21, Руководство по установке, использованию и обслуживанию

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11) 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. Intrinscially 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.
12) 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.
13) 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
14) Leak detection methods
The following leak detection methods are deemed acceptable for systems containing flammable refrigerants.
Electronic leak detectors shall be used to detect flammable refrigerants, but the sensitivity may not be adequate, or may need re-
calibration.(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.
Leak detection equipment 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 chlorine 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 removed or extinguished. If a leakage of refrigernat is found which requires
brazing, 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 .
Oxygen free nitrogen(OFN) shall then be purged through the system both before and during the brazing process.
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.
10) Repairs to sealed components
a) 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.
b) 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. Instrinsically safe components do
not have to be isolated prior to working on them.
11 SERVICE INFORMATION