Table 3-4
Gas supply
Instrument air
● At least 350 kPa (50 psig) for units with Model 11 or Valco valves
● At least 825 kPa (120 psig) for units with Model 50 valves
● At least 175 kPa (25 psig) for airbath ovens; 85 l/min per oven
● Instrument air quality requirement: ISO-8573-1:2010 [3:2:3]
[ 3 : - : - ] Dust filtering down to 1 micron
[ - : 2 : - ] Dew point of -40°C
[ - : - : 3 ] Total hydrocarbon below 1 mg per cubic meter (appr. 0.8 ppmw)
Carrier gas
● Hydrogen, Nitrogen, Helium, Argon, or Synthetic Air in compressed gas cylinder,
purity 99.999%, or hydrogen with a purity of 99.999% (depending on application).
● Typical consumption quantity: 5 to 100 l/month per detector module
Corrosion protection
● Purging with dry air to protect the electronics
● Airbath oven with stainless steel lining
● Airless oven made of aluminum
● Steel lining painted on outside (epoxy powder coating)
These are general parameters that vary depending on the individual application and
configuration.
Table 3-5
Typical Gas Requirements
Type
Quality
Pressure
Typical Consumption
Carrier gas
Hydrogen
Nitrogen
Helium
Argon
Synthetic Air
5.0 (≥ 99,999%)
500 to 1000 kPa (72.5 to
145 psig)
50 to 150 ml/min/train
Combustion gas Hydrogen
5.0 (≥ 99,999%)
500 to 1000 kPa (72.5 to
145 psig)
30 to 50 ml/min/FID
Approx. 100 ml/min/FPD
Combustion air
Synthetic air
Hydrocarbon free
500 to 1000 kPa (72.5 to
145 psig)
Approx. 400 ml/min/FID
Approx. 100 ml/min/FPD
Actuation air
Instrument air
Purge air
(py purge)
Instrument air
or Nitrogen
Instrument air
400 to 1655 kPa (58 to 240
psig)
Initial purge: Approx. 65l/min
Operating purge: Approx. 3.5 l/min
Purge air
(px purge)
Instrument air
or Nitrogen
Instrument air
400 to 600 kPa (58 to 87
psig)
Initial purge: 60 to 80 l/min
Operating purge: 12 to 18 l/min
Valve gas
(for Model 50)
Instrument air
500 to 1000 kPa (72.5 to
145 psig)
Oven heating
(for Airbath
oven)
Instrument air
400 to 600 kPa (58 to 87
psig)
85 l/min/oven
Vortex cooler
Instrument air
300 to 600 kPa (43.5 to 87
psig)
130 to 170 l/min
PTGC
Instrument air
400 to 600 kPa (58 to 87
psig)
210 l/min
Specifications
Maxum II Reference Manual
94
Manual, 7/2017, 2000596-001
