Dwyer-Photohelic Switches/ Gauges

General:

Using solid state technology, the Series 3000MR and 3000MRS Photohelic® switch/gauges combine the functions of a precise, highly repeatable differential pressure switch with a large easy-to-read analog pressure gauge employing the durable, time-proven Magnehelic® design. Switch setting is easy to adjust with large external knobs on the gauge face. Gauge 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 413⁄16" (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.

Gauge accuracy is ±2% of full scale and switch repeatability is ±1%.

Switch deadband is one pointer width — less than 1% of full scale.

Compatible with air and other non-combustible, non-corrosive gases, they can be used in systems with pressures to 25 psig (1.725 bar). Optional construction is available for use to either 35 psig (2.42 bar) or 80 psig (5.51 bar).

Specifications:

Service

Air and non-combustible, compatible gases.

Accuracy

±2% of full scale (3000-0 ±3% of full scale). (3000-00 +4% of full scale).

Pressure Limit

20˝ Hg. to 25 psig (-0.677 bar to 1.72 bar). MP option;35 psig (2.41 bar), HP option; 80 psig (5.52 bar).

Temperature Limits

20 to 120°F. (-6.67 to 48.9°C).

Process Connections

1/8-27 female NPT (duplicated side and back).

Size

4˝ (101.6 mm) dial face, 5˝ (127 mm) O.D. x 3-1/8˝ (79.38 mm).

Weight

1.8 Ib (816 g).

Switch Specifications 3000MR

Switch Type

Each setpoint has a 1 Form C relay (SPDT).

Relay Contacts

(resistive load) 1 Form C rated 1.0A @ 30 VDC, 0.3A @110 VDC or 0.5A @ 125 VAC. Gold over clad silver - suitable for dry circuits.

Electrical Connections

18˝ (46 cm) cable assembly with 8 conductors.

Optional lengths to 100´ (30.5 m).

Power Requirements

24 VDC, regulated ±10%.

Mounting Orientation

Diaphragm in vertical position. Consult factory for

other position orientations.

Set Point Adjustment

Adjustable knobs on face

Switch Specifications 3000MRS

Switch Type

Each setpoint has a solid state relay.

Switching Voltage

20-280 VAC (47 - 63 Hz).

Switching Current:

1.0 amp (AC) max., 0.01 mA (AC) min., (2) SPST N.O.

Electrical Connections:

18˝ (46 cm) cable assembly with 6 conductors, Optional lengths to 100´ (30.5 m).

Power Requirements:

24 VDC, regulated ±10%.

Mounting Orientation:

Diaphragm in vertical position. Consult factory for other position orientations.

Set Point Adjustment:

Adjustable knobs on face.