Dwyer MS 121 Magnesense Differential Pressure Transmitter

About Dwyer MS 121 Magnesense Differential Pressure Transmitter

Dwyer Instruments MS-121-LCD

Differential Pressure Xmitter 0.5"H2O,Panel Mount,LCD

The Series MS Magnesense Differential Pressure Transmitter is an extremely versatile transmitter for monitoring pressure and air velocity. This compact package is loaded with features such as: field selectable English or metric ranges, field upgradeable LCD display, adjustable dampening of output signal (with optional display) and the ability to select a square root output for use with Pitot tubes and other similar flow sensors. Along with these features, the magnetic sensing technology provides exceptional long term performance and enables the Magnesense transmitter to be the solution for a myriad of pressure and flow applications. Field Upgradeable LCD. No need to order two separate transmitters. Simply stock a transmitter and display and you can satisfy any customer's requests. Simply remove cover and snap the LCD onto the board. Field Selectable Ranges in metric or English. Lowers stock and inventory requirements. You'll always have the right transmitter for every job. Digital Push Button Zero and Span. Reduces calibration time significantly over other transmitters that utilize potentiometers. Lowers maintenance time and costs. Adjustable Digital Dampening smooths out unstable pressure fluctuations common in air flow applications. Field Selectable Air Velocity Mode for fan and blower applications. Unit provides square root output that accurately tracks fpm or m/s flow rate. No need for a smart programmable indicator or PLC to convert pressure to air flow. Reduces components and installation time lowering overall costs

Product Highlights

• 4-20 mA output
• Selectable Range 0.1", 0.25"
• 0.5 in H2O. (25, 50, 100 Pa)
• panel mount
• with LCD

Compact and Robust Design

The MS 121 is engineered for industrial environments, featuring a durable polycarbonate enclosure graded to IP66 (NEMA 4X) standards for protection against dust and water ingress. This ensures longevity even in challenging conditions, making it suitable for both indoor and outdoor installations. Its light weight and streamlined form simplify wall mounting and integration into existing systems.


Flexible Output and Easy Adjustment

This transmitter offers selectable output signals (4-20 mA or 0-10 VDC), allowing users to match the transmitter to their system requirements. With push-button zero and span adjustments, field calibration is enabled without hassle. The screw terminal block ensures secure and straightforward electrical connections for both professionals and maintenance staff.


High Accuracy and Fast Response

With 1% of full scale accuracy at 21C and a response time under 500 ms, the MS 121 delivers reliable and swift pressure readings. This high precision ensures that processes dependent on accurate pressure measurement, such as air filter monitoring and cleanroom control, operate safely and efficiently.