S122-30-60-PSI-VM is a Brooks Instrument 122 Series mechanical pressure gauge for local pressure indication in high-purity gas systems. Its configured code identifies a 2-inch, stem-mounted stainless-steel gauge with a compound range from 30 inHg vacuum through zero to 60 psi and a face-seal male process connection
Configurations vary. Verify the exact unit before choosing a replacement.
Application classSemiconductor/high-purity gas delivery
CategorySensors and Gauges
Specifications
Identification
Manufacturer
Brooks Instrument
Series and model
122 Series, model S122
Configuration
Gauge type
Mechanical indicating compound pressure gauge
Socket orientation
Stem mounted
Dial size
2 in
Pressure range
30 inHg vacuum through zero to 60 psi
Connection
VM face-seal male
Performance
Accuracy
1% of full scale
Helium leak check
4 × 10^-9 inboard std. cc/sec
Proof pressure
110%
Burst pressure
400%
Temperature
Operating ambient range
0 to 160 °F (-18 to 71 °C)
Compensating range
20 to 135 °F (-7 to 57 °C)
Storage range
-20 to 135 °F (-29 to 79 °C)
Construction
Case
Electropolished 300 Series stainless steel
Bezel and lens
One-piece screw-on polycarbonate
Socket
316L stainless steel
Movement
300 Series stainless steel
Bourdon tube
316L stainless steel
Cleanliness and safety
Cleaning
Cleaned for oxygen service to ANSI B40.1 Level IV specifications
Standard finish
32 Ra
Safety relief
Unrestricted rear blow-out plug
Display
Dial markings
White dial with black markings and red “Use No Oil” text
Physical
Approximate shipping weight
0.5 lb (0.23 kg)
What Does S122-30-60-PSI-VM Mean?
The identifier follows the documented 122 Series configuration-code structure.
Segment
Field
Interpretation
S
Socket orientation
Stem mounted
122
Model/series
2-inch stainless-steel gauge
30-60
Pressure range
Compound range corresponding to the documented 30-0-60 range: 30 inHg vacuum through zero to 60 psi
PSI
Engineering units
Positive pressure is indicated in pounds per square inch; the compound vacuum portion is indicated in inches of mercury
VM
Process connection
Face-seal male
Legacy Status and Replacement
Brooks lists models C122 and S122 as legacy pressure gauges and directs users to the current PG Mechanical Pressure Gauges. The family-level replacement link does not establish drop-in interchangeability for this configured unit; dial size, stem orientation, compound span, connection dimensions, and installation clearance must be matched before substitution.
