About Dwyer 3020MRS Photohelic Switch/Gauge 0 to 20 inch
Dwyer 3020MRS Photohelic Switch/Gauge 0 to 20 inch
Series 3000MR/3000MRS Photohelic® Switch/Gage
Combines Differential Pressure Gage with Low/High Set-Points,Compact Size
| Model | Description |
| 3020MRS-20 inch | Pressure Switch/Gage,Range 0-20 inch, .50 minor divisions. |
Includes
- mounting ring, snap ring
- 18" cable assembly
- (2) 3/16" tubing to 1/8" NPT adapters
- (2) 1/8" NPT pipe plugs
- (4) 6-32 x 1-1/4" RH machine screws (panel mounting)
- (3) 6-32 x 5/16" RH machine screws (surface mounting)
he Series 3000MR Photohelic® Switch/Gage 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" hole or surface mounted with hardware supplied. 3000MR models employ versatile electromechanical relays with gold over silver contacts - ideal for dry circuits.
Gage 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.
Applications
- Fan Control
- Damper Control
- Environmental Pollution Control
Approvals
- CE Approval
- GOST-R Certificate
Specification
| Service | Air and non-combustible, compatible gases |
| Accuracy | ±2% of FS at 70°F |
| Pressure Limits | -20" Hg to 25 psig |
| Temperature Limits | 20 to 120°F |
| Process Connections | 1/8 female NPT (duplicated side and back) |
| Size | 4" dial face, 5" O.D. x 3-1/8" |
| Weight | 1.8 lb |
| Switch Specifications | |
| Switch Type | Each setpoint has 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" cable assembly with 8 conductors |
| Power Requirements | 24 VDC, regulated ±10% |
| Mounting Orientation | Diaphragm in vertical position |
| Set Point Adjustment | Adjustable knobs on face |
| Agency Approvals | CE
|
Versatile Pressure Measurement and ControlThe 3020MRS model from Dwyer combines both measurement and switching functionality for differential pressure in a single compact unit. Its dual DPDT relays, instantaneous response, and external setpoint adjustments make it suitable for automation sequences or HVAC system management, providing precise switching at critical pressure points with ease.
Rugged, Industrial-Grade ConstructionManufactured with a die-cast aluminum housing and sealed with silicone rubber, the Dwyer 3020MRS is built to withstand challenging industrial settings. The IP54 front-panel rating ensures resistance to dust and splashes, while the internal components, made from stainless steel and bronze, provide extended operational reliability and accuracy over time.
Simple and Efficient InstallationDesigned for vertical mounting, the 3020MRS offers flexible installation optionspanel or surface mountfitting seamlessly into existing setups. Threaded 1/8 NPT female pressure ports and included accessories, such as a mounting bracket and terminal screws, ensure a straightforward, quick installation process.
FAQs of Dwyer 3020MRS Photohelic Switch/Gauge 0 to 20 inch:
Q: How do I correctly install the Dwyer 3020MRS Photohelic Switch/Gauge?
A: For optimal performance, the 3020MRS should be mounted in a vertical orientation, using the supplied mounting bracket and terminal screws. The unit can be installed onto a panel or surface, and the 1/8 NPT female ports should be connected to the high and low pressure sources. Ensure all electrical wiring complies with its 120/240 VAC, 10A ratings.
Q: What applications are best suited for the 3020MRS Photohelic Switch/Gauge?
A: This instrument excels in industrial environments where monitoring and controlling differential air or gas pressure is critical. It is ideal for HVAC systems, duct static pressure monitoring, filter status indication, and process automation requiring reliable pressure switching and indication.
Q: When should I adjust the set points on the 3020MRS, and how is it done?
A: Set point adjustments are necessary whenever your process parameters change or maintenance is performed. You can alter the switch points easily from the front panel using the external adjustment knobs without dismantling the unit, ensuring minimal downtime.
Q: Where is the best place to mount the 3020MRS in my system?
A: Vertical mounting is recommended, near the point where you need to monitor or control differential pressure. Ensure accessibility to the front panel for adjustments, and proximity to both high and low pressure lines to simplify piping.
Q: What is the installation process for integrating the 3020MRS with my equipment?
A: Begin by securing the gauge to the panel or designated surface using the mounting bracket. Connect the pressure ports to your systems high and low pressure sides with compatible tubing. Next, wire the relays according to your switching requirements, referencing the instruction manual, and power the unit with the correct voltage.
Q: How does using the 3020MRS benefit my process control?
A: The integrated gauge and adjustable relay switches offer real-time pressure indication and automatic switching, improving system reliability and response. Quick set-point changes and instantaneous relay actuation streamline process adjustments and enhance safety by promptly reacting to abnormal pressure conditions.