
Pressure
Controller/Calibrator
Theory of Operation
11
Pneumatic Interfaces
All PMMs use the same pneumatic interface. See Figure 2.
1
3
2
4
6
7
5
PMM Pneumatic Interface
PCM Pneumatic Interface
hxn028.eps
Reference
port
Supply
port
Test
port
Guide bushing, threaded rods
Alignment
bushing
Test
port
Reference
port
Figure 2. Pneumatic Interface
Over Pressure Protection
Relief Valves
- The main chassis contains two relief valves:
•
A 3500 psi relief valve that protects the pressure supply input.
•
A 120 psi relief valve on the exhaust port that limits exhaust port blockage.
Each PMM contains an overpressure protection device (resettable pressure
release valve). These valves are set to protect the module’s internal sensor. For
PM600, the relief valves are typically set to 10 % to 15 % over the module FS.
The PM200 are set higher based on how the sensors are scaled.
The chassis design prevents hazardous conditions that result from improper
connection of supply and accidental pressure over-range.
The main firmware has a user-settable autovent function to vent the system if
pressure is greater than autovent level.
All solenoids in the chassis are normally closed. In a power-off condition, all
pressure is trapped in the system to avoid rapid pressure changes. Remove the
pressure supply to reduce pressure in the entire system. The pressure in the
system is reduced to approximately 150 psi as pressure decreases through the
reversed-biased solenoids.
Содержание 6270A
Страница 5: ...Contents continued iii Inspect and Replace the CPS valves 122 Replacement Parts 124 Screw Torque 136...
Страница 6: ...6270A Service Manual iv...
Страница 26: ...6270A Service Manual 20 2 1 3 hxn212 eps Figure 7 PMM and PCM Removal...
Страница 30: ...6270A Service Manual 24 1 2 3 hxn205 eps Figure 9 Manifold Installation...
Страница 32: ...6270A Service Manual 26 2 1 1 hxn202 eps Figure 10 Remove Feet and Tilt Stands...
Страница 37: ...Pressure Controller Calibrator Module Guide Rails 31 1 2 3 hxn209 eps Figure 13 Remove Module Guide Rails...
Страница 40: ...6270A Service Manual 34 hxn208 eps Figure 16 Remove the CPU...
Страница 43: ...Pressure Controller Calibrator Module Guide Rails 37 8 9 10 hxn219 eps Figure 18 Dock Assembly...
Страница 47: ...Pressure Controller Calibrator Module Guide Rails 41 2 3 1 4 6 7 5 8 hxn215 eps Figure 21 Remove B Series Valve...
Страница 53: ...Pressure Controller Calibrator Power Supply and Fan 47 3 1 2 4 hxn221 eps Figure 25 Remove Power Supply...
Страница 64: ...6270A Service Manual 58 1 2 3 4 5 7 6 hxn210 eps Figure 32 Remove Latch Assembly...
Страница 67: ...Pressure Controller Calibrator PCM Assembly 61 2 1 hxn401 eps Figure 34 Module Components...
Страница 138: ...6270A Service Manual 132 9 2 5 18 7 9 8 2x 9 5x 3 4x 4 3x 7 2x 11 12 13 6 10 hxn509 eps Figure 56 PMM CAL KIT 20M Parts...