PIETRO FIORENTINI REVAL 182, Use And Maintenance Instructions

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45
REV
AL 182
Use, maintenance and warning instructions
MEDIUM PRESSURE REGULATOR | DESCRIPTION AND OPERATION | REV. 00
EN
4.5.2.2 - V/25 AND M/A ACCELERATING VALVES
NOTICE!
To use the monitor as a safety accessory according to Directive 2014/68/EU 'PED', installing V/25 or M/A
accelerating valves is recommended.
In the event of malfunctions of the main regulator (2), to speed up tripping of built-in monitor PM/182 (1), accelerating
valves will be installed
• V/25 (3, fig. 4.9), in the case of downstream pressure (Pd) up to 0.6 bar;
• M/A (3, fig. 4.10), in the case of downstream pressure (Pd) from 0.55 bar.
The accelerating valve, based on a downstream pressure signal (Pd), discharges the gas contained in the loading cham-
ber of the monitor into the atmosphere, thus enabling more rapid tripping.
The setting of the accelerating valves must be higher than the monitor's cut-off pressure (1) with reference to the specific
cut-off pressure value (refer to the identification plates in par. 2.8).
Calibration is performed by turning:
• the adjustment ring nut (4, fig. 4.9) for valve V/25
• the adjusting screw (4, fig. 4.10) for the M/A valve
clockwise or anticlockwise to increase or decrease its value.
Accelerating valve Set Operating range (bar)
V/25 max 0.015 - 0.6
M/A max > 0.55
Tab. 4.21.
2
1
3
4
SFIATO
U
pstream press
. D
ownstream press
. p
re
-
regULator pressUre
m
onitor LoaDing press
.
Fig. 4.9. V/25 accelerating valve