Buyer’s Guide to Finding Differential Pressure Gauges, Switches, and Transmitters in the Midwest

November 15, 2020

Mid-West Instrument offers a wide variety of gauges, switches, and transmitters, along with opportunities for customization. Serving Michigan business for more than 60 years, we are an instrument manufacturer serving the Midwest. We have a great deal of combined experience and expertise, and this buyer’s guide can help acquaint you with our many options.

Gauge Examples

Mid-West Instrument offers numerous differential gauges to satisfy a large number of applications. Some of our most popular gauges used by a variety of companies in the Midwest include:

Piston Type Gauge

Our piston type gauges come in either (+/-) 2% or (+/-) 5% Full-Scale Accuracy and are popular for liquid applications. These gauges are available with either 1 – 2 hermetically sealed reed switches or a 4-20mA transmitter, depending on the model. Moreover, a select number of piston type gauges are configurable for use in hazardous environments.

Diaphragm Type Gauge

Diaphragm type gauges feature high- and low-pressure ports that are completely isolated from each other. This negates any bypass and makes these gauges ideal for use with dissimilar air, gases, and liquids. Diaphragm type gauges also work for a broad range of sensitivity measurements, the result of our experience with designing these gauges in a variety of sizes.

Bellows Type Gauge

Available in (+/-) 1/2% or (+/-) 1 % Full-Scale Accuracy, the main components found in many bellows-type gauges are a torque tube assembly, a gauge front assembly, an over-pressure assembly, and a bellows sensing element, all housed in a two-piece body. These gauges can also be equipped with a micro-switch, which is triggered by the rotation of a cam that’s mechanically linked to the bellows.

Bourdon Tube DP Gauge

Bourdon tube differential gauges are available in (+/-) 1/2% or (+/-) 1 % Full-Scale Accuracy.  Similar to the traditional pressure gauge, a bourdon tube changes shape when pressure is applied.   Differential pressure bourdon tube gauges have a high pressure chamber that encapsulates the bourdon tube assembly.   The instrument measures the difference in pressure between the process fluid inside the tube to the pressure in the chamber.   The difference is accurately displayed on the dial.


The differential pressure switches and relays we furnish for customers in the Midwest are used to alert customers of process conditions, or control process equipment at pre-set values. SPST (single pole single throw) and SPDT (single pole double throw) outputs are available, as well as Normally open and Normally closed outputs.  Our hermetically sealed reed switches come with or without enclosures, and most models with enclosures carry a NEMA 4X environmental rating. Mid-West Instrument reed switches are field adjustable, and all are preset to 50% of full-scale range unless otherwise specified by the customer. Also, two switch units can be set independent of each other.


Our differential pressure gauge/transmitter provides a real-time, 4-20 ma signal of process conditions. And whether the transmitter is indicating or non-indicating, each one is designed as a 2-wire loop powered microprocessor-based 4-20 ma transmitter. An 11-point calibration linearization technique is used to individually calibrate each transmitter to its gauge – a method that delivers a <2% accuracy for the upper 80% of the range. Plus, an external zero pin is available for simple zeroing after installation.

Get High-Quality Instruments Today

Whether you need a bellows-type gauge, a hermetically sealed switch, or a differential pressure transmitter for your business in the Midwest, Mid-West Instrument in Sterling Heights has you covered. Contact us today and tell us what you need to take your business to a higher level of performance.