Idiomas disponibles
Idiomas disponibles
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
•
Ensure that apparatus is mounted securely.
•
Ensure that seals or sealing materials have not degraded such that they no longer serve
The use of silicon sealant may inhibit the effectiveness of some types of leak detection
NOTE:
equipment. Intrinsically safe components do not have to be isolated prior to working on them.
8.
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
ignition of refrigerant in the atmosphere from a leak.
9.
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.
10.
Under no circumstances shall potential sources of ignition be used in the searching for or detection
11. Leak detection methods
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 used. 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
most refrigerants but the use of detergents containing chlorine shall be avoided as the chlorine may
shall be removed/ extinguished. If a leakage of refrigerant 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.
12. Removal and evacuation
When breaking into the refrigerant circuit to make repairs or for any other purpose conventional
is a consideration. Opening of the refrigeration systems shall not be done by brazing. The following
procedure shall be adhered to:
•
Remove refrigerant;
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