16
ES
FR
EN
IT
FRG/2MBC(Z-F-R-M) - FRG/2MB(Z-F-R-M)
Madas Technical Manual
- 5|5.1b - REV. 0 of 15
th
Feb 2019
6.2 - Adjusting the minimum pressure shut off (UPSO)
• Unscrew the cap (
10
);
• Use the supplied key (
28
) to loosen the adjustment ring nut of the minimum shut off (
17
) to the minimum;
• Start the system and reset the shut off device as described in 4.0;
• Reduce the downstream pressure to the desired trigger value;
• Use the supplied key (
28
) to tighten the adjustment ring nut (
17
) until the minimum pressure shut off is triggered.
• Reset the system by following the correct procedure and verify that the trigger value is that desired by repeating the release
step 2-3 times;
• If necessary, adjust the trigger value by turning the ring nut (
17
) with the specific key (
28
);
6.3 - Adjusting the relief valve (differential DfRv)
NOTE:
The relief (if present) in these regulators is differential, therefore the value of the range (DfRv) indicated must be added
to the value of the output pressure range (Pa).
Example: Pa=20
÷
30 mbar - DfRv=10
÷
60 mbar.
It means that the relief can be set from: (Pa min + DfRv min) = 20+10=30 mbar to: (Pa max + DfRv max) = 30+60=90 mbar
So the relief range (in this case) is 30
÷
90 mbar.
• Start the system and set the shut off as described in point 4.0;
• Slowly close the valve downstream of the regulator;
• Loosen and remove the cap (
27
);
• Use the 8 mm socket spanner (see fig. 1a and 2a) to fully tighten the nut (
26
);
• Use the 8 mm socket spanner to press the adjustment nut (
26
) and increase the pressure Pa, reading it on the pressure
gauge, up to the desired set value;
• Without pressing further, slowly loosen the adjustment nut (
26
) until the pressure Pa begins to decrease, shown on the
pressure gauge;
• In this case, the relief valve is set to the desired value;
• Remove the socket spanner and close the cap (
27
).
6.4 - Adjusting the outlet pressure (Pa)
The outlet pressure Pa (unless specifically requested) is factory-set with the regulator installed as indicated in 3.4 and with
the adjustment screw (
1
) set approximately at the minimum setting value. The safety shut offs/relief valve are set accordingly;
If the regulator is installed in different positions, check and reset the outlet pressure Pa, and consequently the devices
incorporated in the regulator;
Adjust the outlet pressure as follows:
• Unscrew the cap (
27
);
• Unscrew the adjustment screw (
1
) and set it to the minimum setting allowed (threaded end of the top cover (
20
));
• Start the system or make sure there is a minimum flow downstream of the regulator;
• To increase the pressure setting downstream of the regulator, tighten the adjustment screw (
1
) to the desired value. Perform
the reading with a calibrated pressure gauge, installed downstream of the regulator to at least 5 DN (see example in 3.4);
• Screw the cap (
27
) back on and if necessary, seal it in that position using the appropriate seal holes (if any);
• Use pressure outlets (
23
) on the device only for zero flow or very low flow measurements.
7.0 - RECOMMENDED PERIODIC CHECKS
• Use a suitable calibrated tool to ensure that the bolts are tightened as indicated in 3.2;
• Check the tightness of the flanged/threaded connections on the system;
• Check the tightness and operation of the regulator/shut off/relief valve;
The final user or installer is responsible for defining the frequency of these checks based on the severity of the service conditions.
