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MDE-4334C Atlas Start-up and Service Manual · April 2008
Hydraulic/Mechanical Components
Measuring Pressure and Vacuum
Pressure Measuring Locations on Unit
For Dispensers
Install the pressure gauge at any one of the following locations. Refer to
on
.
To Check
Insert the Pressure Gauge in the
Inlet pressure (pressure available to dispenser)
Shear valve test port (location A)
Filter cap port pressure (pressure available at filter)
Special filter cap port fitting (location B)
Discharge pressure (pressure available to hanging
hardware)
Special discharge fitting (location C)
Figure 7-7: Typical Pressure Gauge Installations
20
30
0
60
10
50
40
20
30
0
60
10
50
40
20
30
0
60
10
50
40
Test Point
Location A: Pressure Gauge
in Shear Valve
(Dispenser only)
Location B: Pressure
Gauge in Filter Cap Port
Special Discharge
T-fitting
Location C: Pressure Gauge in
Discharge Fitting
Measuring STP Pressure for Dispensers
To measure STP pressure for dispensers, proceed as follows:
1
Shut off power to the STP.
2
Verify if the dispenser and STP have been deactivated.
3
Always use eye protection. Install the gauge at the shear valve test port. Refer to
,
Location A.
4
Activate the nozzle. Do not pump fuel.
5
Read the psi reading on the gauge. The operating pressure depends on the STP horsepower.
Consult the manufacturer for the exact performance values.
Note: The pressure at the dispenser inlet will reduce when the dispenser is dispensing fuel.
Pressure drop of more than a few psi may indicate an inadequately sized STP,
underground restrictions, inadequately sized plumbing, or a defective STP.