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ML435 | v23
Expo Technologies UK
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Section 7: Commissioning
Commissioning the System
Note: The steps 11 and 15 to 21 represent detailed commissioning tests
The following equipment is needed for this process:
• Continuity meter
• Gauge manometer (0 to 200 mbarg)
• Differential manometer
If, after commissioning, the system does not perform as expected, refer to the
Fault Finding
Section.
Follow the steps as outlined:
1. Check all connections and that the Relief Valve Unit is fitted correctly with an unobstructed path to the purge
exhaust.
2. Close the Purge Flow Restrictor Valve.
3. Fully open external supply shut-off valve where fitted.
4. Check that the internal logic pressure gauge reads 2.3 barg / 33 psi / 230 kPag.
5. Check that the pressure gauge on main air supply reads 5 barg / 73 psi / 500 kPag.
6. Check that the Pressure Relief Valve is correctly set by disconnecting the minimum pressure sensing pipe at
the bulkhead fitting on the input to the MiniPurge
®
. This will disable all of the pressure sensors.
• Using a 4 mm nylon tube, connect a manometer to the bulkhead fitting from which the minimum pressure
sensing pipe was removed.
• Open the Purge Flow Restrictor Valve very slowly, until the Pressure Relief Valve opens
• Check the opening pressure is within calibration limits.
• This test can be carried out several times to ensure repeatability and compliance.
Refer to the
Maintenance of the System
section if the Relief Valve needs recalibrating.
7. Close the Purge Flow Restrictor Valve.
8. Remove the manometer and reconnect the minimum pressure sensing pipe to the bulkhead fitting.
9. Remove red plug from the top of the Minimum Pressure Sensor and connect a gauge manometer.
10.Connect a differential manometer to the test points on the flow sensor.
11.To check sensor calibration
• The internal pressure in the pressurized enclosure must be below Relief Valve lift off pressure and above
the CLAPS pressure
• At this time the pressurized indicator should be
green
.
• gradually open Purge Flow Restrictor Valve until purging indicator
flashes
yellow
.
Note: For large volumes it may take a long time for the purge flow to start.
• very slowly close Purge Flow Restrictor Valve until the purging indicator stops
flashing yellow.
• Take a reading from pressure gauge.
12.To set the purge flow rate:
• Turn on the compressed air to the MiniPurge
®
.
• Gradually open the Purge Flow Restrictor Valve until the
black / yellow
indicator changes to
yellow
(flashing)
.
• The flashing yellow indicator confirms the correct flow rate.
• The differential pressure should be greater than 6.4 mbarg.
