Model 120 "Piston Type"

Differential Pressure Gauge & Switch

Model 120 – The Mid-West Instrument piston type gauge is our most versatile and customizable differential pressure gauge to fit your most demanding requirements. Available with multiple switch options including Hazardous location options. With a Full scale accuracy of ±3/2/3% combined with Differential pressure dial scales of 0-5 PSID to 0-110 PSID this rugged design is ready to do the job.

Product Features/Benefits

Simple Rugged Piston Type Design Sensing Element
Glass Reinforced Thermoplastic DIal Case (Panel Mountable) (Anodized Aluminum Dial Case Option available contact sales for more information)
Weather Resistant & Corrosion Resistant
Shatter Resistant Lens
Over-Range Protection, High over Low and Low over High
5 Year Warranty
For complete model details see BULLETIN_120
Installation and Operation Manual see IOM_120

Specifications

Dial Sizes available: 2-1/2", 3-1/2", 4-1/2", and 6" Diameters (Uni-Directional & Bi-Directional)
Differential Full Scale Ascending Accuracy ±3/2/3% (ASME B40.1 Grade B)
Dial Scale Ranges: 0-5 PSID to 0-110 PSID (0-0.35 to 0-7.0 bar)
Available in a Variety of Dial Scales: PSID, Bar, Mbar, kPa, Kg/Cm2, Dual Scale etc.
Working Pressures up to 6000 PSIG (400 Bar)
Operating Temp -40ºF to +200ºF (-40ºC to +93ºC)
Weather Protection NEMA 4X
Material of Construction of Body - Aluminum, 316/316L Stainless Steel, Alum/Bronze and Monel (Wetted Part)
Internal wetted parts-316 Stainless Steel, Ceramic Magnet, Alum/Bronze, Monel (Dependent on model chosen)
Elastomers (O-rings) Buna-N, Viton, Neoprene, Teflon, Ethylene Propylene (Perfluoroelastomer optional)

Common Applications

Filters and Strainer Monitoring
Compressed Air
Hydraulic
Refrigerant
Pump Performance Testing
Heat Exchanger Pressure Drop Monitoring
Valves, Chillers etc.. and for local flow indication and control.

Mid-West Instrument switches are mechanically adjustable allowing customer to set the switch within a defined adjustment span of range of the instrument. Mid-West can also pre-set switch set point(s) upon customer request.

SPDT 3W, 0.25 Amp, 125 VAC/VDC, ROHS Compliant
SPST 60W, 3.0 Amp, 240 VAC/VDC (Normally Open), ROHS Compliant
SPDT 60W, 3.0 Amp, 240 VAC/VDC (Normally Closed), ROHS Compliant
SPST 60W, 3.0 Amp, 240 VAC/VDC (1) Normally Open,(1) Normally Closed, ROHS Compliant

Electrical Enclosures Weather-Resistant, NEMA 4X or NEMA 7
CE Marked in Accordance With Low Voltage Directive
Hazardous Locations
- Class I Division I, Class II, Division I
- Class I Division II, Class II, Division II

Additional Options:

Pipe Mounting Kit - 2" U-Bolt
Wall Mounting Optional - Rear Mount
Rear Mounting Holes
Liquid Fill
Oxygen Cleaning
Maximum Follower Pointer
NACE Compliance
CRN - Canadian Registration Number Optional

Model No.	Differential Pressure Range	Accuracy	Working Pressure	Electrical Available
121	0-5 PSID to 0-110 PSID (0-0.35 to 0-7.0 bar)	±2%*	-40ºF to +200ºF (-40ºC to +93ºC)	Electrical Enclosures Weather-Resistant, NEMA 4X or NEMA 7
122	0-5 PSID to 0-110 PSID (0-0.35 to 0-7.0 bar)	±2%*	-40ºF to +200ºF (-40ºC to +93ºC)	Electrical Enclosures Weather-Resistant, NEMA 4X or NEMA 7
123	0-5 PSID to 0-110 PSID (0-0.35 to 0-7.0 bar)	±2%*	-40ºF to +200ºF (-40ºC to +93ºC)	Electrical Enclosures Weather-Resistant, NEMA 4X or NEMA 7
124	0-5 PSID to 0-110 PSID (0-0.35 to 0-7.0 bar)	±2%*	-40ºF to +200ºF (-40ºC to +93ºC)	Electrical Enclosures Weather-Resistant, NEMA 4X or NEMA 7
220	0-5 PSID to 0-110 PSID (0-0.35 to 0-7.0 bar)	±2%*	-40ºF to +200ºF (-40ºC to +93ºC)	Electrical Enclosures Weather-Resistant, NEMA 4X or NEMA 7

Model No.

Differential Pressure Range

Accuracy

Working Pressure

Electrical Available

Specifications

Installation/ Operator Manual

Drawing

121

0-5 PSID to 0-110 PSID (0-0.35 to 0-7.0 bar)

±2%*