Dwyer Instruments 1900-20MR Pressure Switch
The Dwyer Instruments 1900-20MR Pressure Switch is a purpose-built low differential pressure switch engineered for critical monitoring in industrial HVAC/R and automation environments. This compact pressure switch operates within an adjustable range of 4.0" to 20.0" w.c., specifically designed for use with clean air and non-combustible gases. Unlike standard auto-reset models, the 1900-20MR features a manual reset mechanism, providing an essential safety layer for fan status monitoring, refrigeration coil icing detection, and clogged filter sensing by requiring a technician to intervene once a setpoint is triggered. Built with a vertical diaphragm and a specialized range screw housed within the conduit enclosure to prevent tampering, this unit ensures high repeatability of ±3%. It utilizes a single SPDT output with 1/8" NPT female process connections, making it a drop-in replacement for contractors managing commercial ovens, dryers, and industrial ventilation systems. The 15A electrical rating at 120-480 VAC ensures compatibility with most heavy-duty control circuits.
Key Benefits- Manual Reset Safety: Prevents system re-starts after an alarm condition until a manual inspection is performed by a technician.
- Repeatable Accuracy: Maintains ±3% repeatability across its 4-20" w.c. range for dependable pressure regulation.
- Tamper-Resistant Design: The internal adjustment screw is protected from unauthorized field modifications.
- Versatile Media Compatibility: Safely handles non-combustible gases, including nitrogen, helium, and standard HVAC air.
- High Electrical Capacity: SPDT switch rated for 15A allows direct control of larger loads or signaling systems.
Can the Dwyer 1900-20MR be mounted horizontally?
The standard diaphragm of the 1900 series is calibrated for vertical mounting. Installing it in other orientations may shift the setpoint and impact accuracy.
What is the maximum pressure limit for this switch?
This differential pressure switch is rated for a continuous pressure limit of 45" w.c. and can withstand a surge up to 10 psig without failure.
How do I reset the switch after it trips?
Once the pressure returns to a normal state below the setpoint, the manual reset button located on the exterior of the housing must be depressed to restore the electrical circuit.
Disclaimer: While we strive for 100% accuracy, product data and specifications are subject to change. Please contact our team to confirm compatibility or technical details before purchasing.
Original: $148.68
-65%$148.68
$52.04Dwyer Instruments 1900-20MR Pressure Switch
The Dwyer Instruments 1900-20MR Pressure Switch is a purpose-built low differential pressure switch engineered for critical monitoring in industrial HVAC/R and automation environments. This compact pressure switch operates within an adjustable range of 4.0" to 20.0" w.c., specifically designed for use with clean air and non-combustible gases. Unlike standard auto-reset models, the 1900-20MR features a manual reset mechanism, providing an essential safety layer for fan status monitoring, refrigeration coil icing detection, and clogged filter sensing by requiring a technician to intervene once a setpoint is triggered. Built with a vertical diaphragm and a specialized range screw housed within the conduit enclosure to prevent tampering, this unit ensures high repeatability of ±3%. It utilizes a single SPDT output with 1/8" NPT female process connections, making it a drop-in replacement for contractors managing commercial ovens, dryers, and industrial ventilation systems. The 15A electrical rating at 120-480 VAC ensures compatibility with most heavy-duty control circuits.
Key Benefits- Manual Reset Safety: Prevents system re-starts after an alarm condition until a manual inspection is performed by a technician.
- Repeatable Accuracy: Maintains ±3% repeatability across its 4-20" w.c. range for dependable pressure regulation.
- Tamper-Resistant Design: The internal adjustment screw is protected from unauthorized field modifications.
- Versatile Media Compatibility: Safely handles non-combustible gases, including nitrogen, helium, and standard HVAC air.
- High Electrical Capacity: SPDT switch rated for 15A allows direct control of larger loads or signaling systems.
Can the Dwyer 1900-20MR be mounted horizontally?
The standard diaphragm of the 1900 series is calibrated for vertical mounting. Installing it in other orientations may shift the setpoint and impact accuracy.
What is the maximum pressure limit for this switch?
This differential pressure switch is rated for a continuous pressure limit of 45" w.c. and can withstand a surge up to 10 psig without failure.
How do I reset the switch after it trips?
Once the pressure returns to a normal state below the setpoint, the manual reset button located on the exterior of the housing must be depressed to restore the electrical circuit.
Disclaimer: While we strive for 100% accuracy, product data and specifications are subject to change. Please contact our team to confirm compatibility or technical details before purchasing.
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Description
The Dwyer Instruments 1900-20MR Pressure Switch is a purpose-built low differential pressure switch engineered for critical monitoring in industrial HVAC/R and automation environments. This compact pressure switch operates within an adjustable range of 4.0" to 20.0" w.c., specifically designed for use with clean air and non-combustible gases. Unlike standard auto-reset models, the 1900-20MR features a manual reset mechanism, providing an essential safety layer for fan status monitoring, refrigeration coil icing detection, and clogged filter sensing by requiring a technician to intervene once a setpoint is triggered. Built with a vertical diaphragm and a specialized range screw housed within the conduit enclosure to prevent tampering, this unit ensures high repeatability of ±3%. It utilizes a single SPDT output with 1/8" NPT female process connections, making it a drop-in replacement for contractors managing commercial ovens, dryers, and industrial ventilation systems. The 15A electrical rating at 120-480 VAC ensures compatibility with most heavy-duty control circuits.
Key Benefits- Manual Reset Safety: Prevents system re-starts after an alarm condition until a manual inspection is performed by a technician.
- Repeatable Accuracy: Maintains ±3% repeatability across its 4-20" w.c. range for dependable pressure regulation.
- Tamper-Resistant Design: The internal adjustment screw is protected from unauthorized field modifications.
- Versatile Media Compatibility: Safely handles non-combustible gases, including nitrogen, helium, and standard HVAC air.
- High Electrical Capacity: SPDT switch rated for 15A allows direct control of larger loads or signaling systems.
Can the Dwyer 1900-20MR be mounted horizontally?
The standard diaphragm of the 1900 series is calibrated for vertical mounting. Installing it in other orientations may shift the setpoint and impact accuracy.
What is the maximum pressure limit for this switch?
This differential pressure switch is rated for a continuous pressure limit of 45" w.c. and can withstand a surge up to 10 psig without failure.
How do I reset the switch after it trips?
Once the pressure returns to a normal state below the setpoint, the manual reset button located on the exterior of the housing must be depressed to restore the electrical circuit.
Disclaimer: While we strive for 100% accuracy, product data and specifications are subject to change. Please contact our team to confirm compatibility or technical details before purchasing.
