Series 1900 Compact Low Differential Pressure Switches
Set Points from 0.07" to 20" w.c., Repetitive Accuracy within 3%
Our most popular Series 1900 Compact Low Differential Pressure Switch combines advanced design and precision construction to make these switches able to perform many of the tasks of larger, costlier units. Designed for air conditioning service, they also serve many fluidics, refrigeration, oven and dryer applications. For air and non-combustible compatible gases, Series 1900 switches have set points from 0.07 to 20" w.c. (1.8 to 508 mm). Set point adjustment is easy with range screw located inside conduit enclosure. Internal location helps prevent tampering. UL, CE and CSA listed, and FM approved.
CAUTION: FOR USE ONLY WITH AIR OR COMPATIBLE GASES.
Please see Series AT-1900 for ATEX approved.
Product Applications
- Air conditioning refrigeration coil icing detection; defrost cycle intiation.
- Clogged filter detection.
- Variable air volume controller.
Models & Ordering
Specifications
- Service:
- Air and non-combustible, compatible gases.
- Wetted Materials:
- Consult factory.
- Temperature Limits:
- -30 to 180°F (-34 to 82.2°C).
- Pressure Limits:
- 45" w.c. (11.2 kPa) continuous, 10 psig (68.95 kPa) surge.
- Switch Type:
- Single-pole double-throw (SPDT).
- Repeatability:
- ±3%.
- Electrical Rating:
- 15 A @ 120-480 VAC, 60 Hz. Resistive 1/8 HP @ 125 VAC, 1/4 HP @ 250 VAC, 60 Hz. Derate to 10 A for operation at high cycle rates.
- Electrical Connections:
- 3 screw type, common, normally open and normally closed.
- Process Connections:
- 1/8" female NPT.
- Mounting Orientation:
- Diaphragm in vertical position. Consult factory for other position orientations.
- Set Point Adjustment:
- Screw type inside conduit enclosure.
- Weight:
- 1 lb 4.5 oz (581 g).
- Agency Approvals:
- CE, CSA, FM, UL. Optional EXPL Explosion-proof enclosure does not possess any agency approvals.
Features
- Compact size and repeatability, provides a high-value switch for many industrial and OEM applications
- Wide range of models from 0.07 in w.c. to 20 in w.c. can meet exacting OEM specifications for a low pressure switch
- Range screw protected inside enclosure provides simplifies making adjustments but prevents tampering
Options
- Weatherproof Housing - 16 ga. steel enclosure with gasketed cover (NEMA 4, IP66) for wet or oily conditions. Withstands 200 hour salt spray test. Wt. 5 lbs (2.3 kg). Switch must be factory installed. Change 1910 base number to 1911 and add –WP suffix. Example: 1911-1-WP.
- Explosion-proof Housing - Cast iron base with brass cover. Rated Class I, Group D; Class II, Groups E, F, G. (7 lbs). Switch must be factory installed. Change model number to 1911 and add –EXPL suffix. Example: 1911-1-EXPL.
- Manual Reset Model 1900-MR - includes special snap switch which latches on pressure increase above the setpoint. Switch must be manually reset after pressure drops below the setpoint. To order change base model to 1900 and add MR suffix after range number. Example: 1900-10-MR. Available on -1, -5, -10 or -20 ranges only. Option is not UL, CSA or FM listed. NOTE: Manual Reset (MR) option for use only in single positive pressure applications.
Accessories
Model Number | Description | Usually Ships* | Price | Order | |
---|---|---|---|---|---|
A-399 | Duct pressure monitor kit, for use with standard or manual reset model switches. | Less Than 1 Week | $58.50 | Order | |
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A-329 | 1/8" NPT close coupled street ell, brass. | 1-2 Weeks | $7.90 | Order |
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A-489 | 4" 303 SS straight static pressure tip with flange, 1/4" hose barb. | Next Day | $9.20 | Order |
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A-302F-A | 303 SS Static pressure tip with mounting flange, for 3/16" I.D. rubber or plastic tubing. 4" insertion depth, includes mounting screws | Next Day | $12.00 | Order |
Videos
Model Chart
EXAMPLE | 1910 | 00 | AT | Series 1910-00-AT Compact Low Differential Pressure Switch with Conduit, range 0.07-0.15" w.c., with aluminum tag. |
SERIES | 1900 1910 1911 1920 1921 |
Compact Low Differential Pressure Switch Compact Low Differential Pressure Switch with Conduit Compact Low Differential Pressure Switch without Conduit Compact Low Differential Pressure Switch with Conduit and HP Back Port Compact Low Differential Pressure Switch without Conduit, with HP Back Port |
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RANGE | 00 0 1 5 10 20 |
0.07-0.15" w.c. 0.15-0.55" w.c. 0.4-1.6" w.c. 1.4-5.5" w.c. 3.0-11.0" w.c. 4.0-20.0" w.c. |
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OPTIONS | AT B BGAP DPK EXPL G LC MIL MR P PRESET ST VIT WP |
Aluminum Tag Buna-N Diaphragm & O-rings B-Gap Micro Switch Duct Pressure Kit Cast Iron Explosion-proof Housing Gold Contact Switch Less Conduit MIL Switch Manual Reset L-Bracket Mounting Preset Stainless Steel Tag Fluoroelastomer Diaphragm & O-rings Weatherproof Housing |
Approvals
Drawings
Questions
- Question
- Will a Dwyer pressure switch be damaged if the pressure exceeding the maximum set-point is applied to the switch?
- Answer
- No. Not unless the maximum pressure rating of the switch is exceeded.
- Question
- How can a standard 1910 pressure switch be used to sense pressure in an oven operating at 200 degrees Celsius?
- Answer
- Use metal tubing for sensing lines long enough to safely dissipate the heat.
Photo Downloads
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