Additional Test For Gas Installations (Zone 2); Commissioning; Inspection And Maintenance; Fuse Replacement - Agro SMART ATEX Instrucciones De Instalación Y Mantenimiento

2.6

ADDITIONAL TEST FOR GAS INSTALLATIONS (ZONE 2)

The type of protection of that equipment for gases (zone 2) requires an individual verification of the enclosure once
it has all the necessary connections and the enclosure is closed. That test is because of standard EN 60079-15,
which requires that the enclosure, after assembly or after maintenance (see EN 60079-17), a restricted breathing
test shall be performed.
Test requirements are:
"Under constant temperature conditions, the time interval required for an internal pressure of 300 Pa (30 mm
water gauge) below atmospheric to change to 150 Pa (15 mm water gauge) below atmospheric shall be not less
than 80 s."
For that aPG7 cable gland in the upper right back allows performing this test.
To this end the following equipment is needed (or equivalent):
- Differential pressure manometer with 10 Pa minimum resolution
3
- Syringe of 10 cm
- Push-in fitting T-shape
- Flexible tube
- Chronometer
Procedure:
Place a piece of flexible tube between the cable gland and the entry of the push-in fitting T-shape.
In one of the exits of the push-in fitting connect the tube of the differential pressure manometer. In the other
connect the syringe.
Take the appropriate measures in order to assure that no air gets into this system (e.g.: through a stopcock).
Using the syringe extract air from the enclosure interior until the manometer indicates a pressure drop of 300 Pa.
Since then, in 80 s it is necessary that the manometer does not rise above 150 Pa of depression.
Once performed the test, plug the cable gland using its blind plug. Follow the cable gland instructions that can be
found at the end of this manual to assure a correct tightening.
2.7

COMMISSIONING

Once all connections have been performed and, only for zone 2, satisfactorily passed the enclosure restricted
breathing test, commissioning of the equipment shall be done. For instructions about its use see the Operation and
Configuration Manual that comes with every equipment.
2.8

INSPECTION AND MAINTENANCE

WARNING
If for inspection and maintenance purposes it is necessary to open the enclosure, it is
mandatory to perform again the restricted breathing test "nR" for zone 2 installations
(gas). See section 2.6.
Follow the inspection and maintenance requirements from standard EN 60079-17.
Finding out the adequate period between inspections depend on the type of installation, the factors that affect the
deterioration of the equipment, the zone classification and the previous inspections. The maximum period between
periodic inspections shall not exceed three years.
In the inspection the good condition of the front overlay and the closing of the rear cover shall be verified, taking
special care on the seal and nylon washers.
2.8.1

FUSE REPLACEMENT

If on turning on the indicator the display does not light up, the likely cause may be that the fuse is not working
properly.
WARNING
Fuse replacement shall only be performed with power supply unplugged and without the
presence of a gas or dust explosive atmosphere.
WARNING
As it is necessary to open the enclosure to replace the fuse it is mandatory to perform
again the restricted breathing test "nR" for zone 2 installations (gas). See section 2.6.
(minimum)
SMART ATEX – INSTALLATION AND MAINTENANCE MANUAL
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