Compact, Low Cost Switch/Gage

Weatherproof and Explosion-Proof in One Economical Enclosure

The Series MP Mini-Photohelic® differential pressure switch/gage combines the time proven Minihelic® II differential pressure gage with two SPDT switching set points. The Mini-Photohelic® switch/gage is designed to measure and control positive, negative, or differential pressures consisting of non-combustible and non-corrosive gases. Gage reading is independent of switch operation. Switching status is visible by LED indicators located on the front and rear of the gage. Set points are adjusted with push buttons on back of unit. This extremely compact switch/gage is ideal for fume hoods, dust collection, pneumatic conveying and clean room applications.

3-in-1 Indicating Gage, Lo-limit and Hi-limit Control

Photohelic® Switch/Gages function as versatile, highly repeatable pressure switches combined with a precise pressure gage employing the time-proven Magnehelic® gage design. The Photohelic® switch/gage measures and controls positive, negative or differential pressures of air and compatible gases. Standard models are rated to 25 psig (1.7 bar) with options to 35 (2.4) or 80 (5.5 bar) psig. Single pressure 36000S models measure to 6000 psig (413 bar) with a 9000 psig (620 bar) rating. Two phototransistor actuated, DPDT relays are included for low/high limit control. Easy to adjust set point indicators are controlled by knobs located on the gage face. Individual set point deadband is one pointer width – less than 1% of full scale. Set points can be interlocked to provide variable deadband – ideal for control of fans, dampers, etc.

Combines Differential Pressure Gage with Low/High Set-points

Using solid state technology, the Series 3000MR and 3000MRS Photohelic® switch/gages combine the functions of a precise, highly repeatable differential pressure switch with a large easy-to-read analog pressure gage employing the durable, time-proven Magnehelic® gage design. Switch setting is easy to adjust with large external knobs on the gage face. Gage reading is unaffected by switch operation – will indicate accurately even if power is interrupted. Solid state design now results in greatly reduced size and weight. Units can be flush mounted in 4-13/16″ (122 mm) hole or surface mounted with hardware supplied. 3000MR models employ versatile electromechanical relays with gold over silver contacts – ideal for dry circuits. For applications requiring high cycle rates, choose 3000MRS models with SPST (N.O.) solid state relays. All models provide both low and high limit control and include 18-inch (45 cm) cable assemblies for electrical connections.

Differential Pressure Transmitter

NEMA 4X Enclosure, 0.25% FS Accuracy

Positive, negative and differential pressures can be measured within a full span accuracy of ±0.25 with the Series 616W Differential Pressure Transmitter. Units are enclosed in a polycarbonate case, rated NEMA 4X (IP66) and operate by sensing the pressure of air and compatible gases then sending a standard 4-20 mA output signal.

Design enables operation in 2-wire current loops. A wide range of models are available factory calibrated to specific ranges. The span and zero controls are for use when checking calibration. They are not intended for re-ranging to a significantly different span. The LCD (as shown to the left) allows local indication of pressure.

1211 Handy Roll-Up Manometer with Laboratory Accuracy
Dwyer® Slack Tube® Manometers are as accurate as the finest laboratory “U” gages – yet they are made to roll up compactly for easy carrying and to withstand rough usage.

Simply unroll the Dwyer® Slack Tube® Manometer and set up to read static pressure, vacuum, or differential pressure. Magnetic clips hold it firmly to any steel surface or hang it on a nail. Turn connectors one revolution to open. When the pressure is imposed, add the number of inches one column travels up to the number of inches the other column travels down. When reading is completed turn connectors to seal columns, roll up manometer into compact coil and tuck it away in its plastic case or a tool box. No fluid lost. No loose caps or inserts to lose.

Perfect for your living room, den, workshop or office. Instruments are accurate, low-cost and practical. Standard model indicates wind speed directly on liquid filled scale reading in both Miles per Hour (0-80) and Beaufort scale (1-12). Also available is metric model, same as above but reading 0-130 kilometers per hour. To order, specify Mk II Wind Speed Indicator, MPH or Mk II Wind Speed Indicator, KPH.

Molded white plastic instrument has gold tone scale, 7-3/8″W X 5-5/8″H X 1-1/8″D. Includes ABS plastic vane, 50′ tubing, mounting hardware and gage fluid.

The Dwyer® Series 475 Mark III Handheld Digital Manometer is ideal for field calibration, monitoring or trouble shooting HVAC systems, clean rooms or a wide range of other low pressure pneumatic systems. This handy instrument measures positive, negative or differential pressures of air and natural gases in ranges from 1″ w.c. (0.249 kPa) to 150 psid (10.34 bar). The Series 475-FM is approved and is intrinsically safe for hazardous locations, Class 1, Div.1, Group A, B,C, D, T4. Its simple operation and easy to read digital display make it an indispensable test instrument for the plant engineer, industrial hygienist and HVAC technician. When used with a Dwyer® Pitot tube, the Series 475 Mark III can also be used as an air velocity gage.

Single & Dual Pressure Measurement, Electronic Zeroing, ±1.5% Accuracy

Ideal for field or laboratory use, the Model 476A-0 Single Pressure Digital Manometer measures low pressures from -20 to 20″ w.c. with ±1.5% full scale accuracy. Designed especially for the HVAC contractor, the Model 476A-0 can be used to set gas supply pressures, verify pressure switch operation, adjust regulators, check pneumatic systems and computer peripherals. The rugged, handheld unit is constructed with an extruded aluminum case for exceptional durability.

The Series 478A manometer can be used to measure positive, negative, or differential pressures. The unit features selectable units, auto zero, hold and a Min/Max function. Press the Hold key to freeze the current pressure measurement on the display. The 478A manometer includes a zeroing button to null out any minor pressure differences.

Selectable Pressure Units, ±0.5% Accuracy, FM Approved Intrinsically Safe for Hazardous Locations, Class 1, Div. 1, Group A, B, C, D, T4

Series 477 Handheld Digital Manometers are packed with features you need to make low pressure measurement and recording faster, easier and more accurate than ever. First, you can instantly select from up to nine of the most widely used pressure units without having to waste time and risk mistakes with tedious conversions. Next, a non-volatile memory function enables storage of up to 40 readings – perfect for HVAC technicians making Pitot tube traverses of airflow readings across a duct. The Series 477 is FM approved intrinsically safe for hazardous locations, Class 1, Div. 1, Group A, B, C, D, T4.

Precise Air Pressure Measurement, ±0.1% F.S. Accuracy

The Popular Series 477 is now available with 0.1% full scale accuracy in the new Series 477A. The 477A contains a highly accurate differential pressure sensor that offers a 0.1% full scale accuracy on air ranges from 20″ w.c. to 100 psid. Series 477A Handheld Digital Manometers are packed with features needed to make pressure measurements and recording faster, easier and more accurate than ever. Instantly select from up to nine of the most widely used pressure units without having to waste time and risk mistakes with tedious conversions. A non-volatile memory function enables storage of up to 40 readings – perfect for HVAC technicians making Pitot tube traverses of air flow readings across a duct. The 477A is also ideal for maintenance personnel or technicians that require a highly accurate standard to check their instrumentation or equipment to ensure proper performance.