Siemens Maxum II PD PA AP User Manual

Valve Reinstallation
1. Reinstall the valve in the oven and connect all tubing.
Note
Best practice is to seat the fittings in a Valco fitting and not in the Model 50 Valve ports.
This will help increase the life of the valve and reduce the chances of causing the center
plate to bulge from over tightening the fittings. See the AUTOHOTSPOT section for
instructions.
2. Power up and check for leaks. Verify valve operation by running chromatograms.
4.3.5 Model 50 Valve Specifications
Table 4-8 Configuration
Valve Type Double-acting, pneumatically operated
Number of Ports 10
Flow Paths On state: flow between ports 1 & 10, 2 & 3, 4 & 5, 8 & 9
Off state: flow between ports 1 & 2, 3 & 4, 5 & 6, 7 & 8, 9 & 10
Note: flow between ports 6 & 7 is always blocked
Table 4-9 Performance and Requirements
Sample Types Vapor samples only, free of particulates
Actuation Gas Inert gas, particulate free
Switching Time 20 ms (Typical in Maxum gas chromatographs.) In other uses, actual switching time
is dependent on the type of solenoids used to deliver the pneumatic signal to the valve
and the size of the pneumatic tubing to the valve.
Sample Filtration 5 micron
Maximum Actuation Pressure 690 kPa (100 psig)
Minimum Actuation Pressure 140-175 kPa (20-25 psig) higher than maximum carrier gas or sample gas pressure
Maximum Port Pressure
(Carrier or Sample)
515 kPa (75 psig); contact factory for higher pressure options
Minimum Port Pressure
(Carrier or Sample)
35 kPa (5 psi)
Pressure Drop < 35 kPa (5 psi) for 200 scc/min (air) Pressure drop was measured in air at room
temperature with flow from port to port. Actual pressure drop will vary with temperature
and gas type. Pressure drop through the sample loop is dependent on the inside di‐
ameter and length of the sample loop.
Maximum Temperature 120°C (248°F); contact factory for higher temperature options
Carrier Gas Flow 0.3 ml/min to 40 ml/min; contact factory for higher flow options
Mean Time Between Failures >10
7
cycles at 60°C (140°F); >4×10
6
cycles at 150°C (300°F). Valve failure is typically
caused by particulates preventing the diaphragms from sealing against the center plate
or long term wear resulting in deformation of the diaphragms.
Valves
4.3 Model 50 Valve
Maxum II Valves and Oven Components
Service Manual, 10/2018, A5E42019844001 53

Siemens Maxum II PD PA AP Specifications

General

Brand	Siemens
Model	Maxum II PD PA AP
Category	Control Unit
Language	English