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Series 1800 Low Differential Pressure Switch for General Industrial Service

Series 1800 Low Differential Pressure Switch for General Industrial Service

Series 1950 Explosion-proof Differential Pressure Switch

Series 1950 Explosion-proof Differential Pressure Switch

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.

California Residents:  Click Here for Proposition 65 WARNING.

Product Applications

    • Air conditioning refrigeration coil icing detection; defrost cycle intiation.
    • Clogged filter detection.
    • Variable air volume controller.
 
 
Starting at $70.00
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Grouped product items
Model Description Availability* Qty Price
1900-5-MR Differential pressure switch, range 1.40-5.5" w.c., approx. deadband @ min. set point 0.30, approx. deadband @ max. set point 0.30, with manual reset option. 1-3 days*
$111.25
1900-10-MR Differential pressure switch, range 3.0-11.75" w.c., approx. deadband @ min. set point 0.40, approx. deadband @ max. set point 0.40, with manual reset option. 1-3 days*
$111.25
1910-00 Differential pressure switch, range 0.07-0.15" w.c., approx. deadband @ min. set point 0.04, approx. deadband @ max. set point 0.04. 1-3 days*
$75.00
1910-0 Differential pressure switch, range 0.15-0.5" w.c., approx. deadband @ min. set point 0.10, approx. deadband @ max. set point 0.10. 1-3 days*
$70.00
1910-1 Differential pressure switch, range 0.40-1.6" w.c., approx. deadband @ min. set point 0.15, approx. deadband @ max. set point 0.16. 1-3 days*
$70.00
1910-5 Differential pressure switch, range 1.40-5.5" w.c., approx. deadband @ min. set point 0.30, approx. deadband @ max. set point 0.30. 1-3 days*
$70.00
1910-10 Differential pressure switch, range 3.0-11.75" w.c., approx. deadband @ min. set point 0.40, approx. deadband @ max. set point 0.40. 1-3 days*
$70.00
1910-20 Differential pressure switch, range 4.0-20.0" w.c., approx. deadband @ min. set point 0.40, approx. deadband @ max. set point 0.50. 1-3 days*
$70.00
1911-00 Differential pressure switch, SPDT, range .07 - .15" w.c. less conduit enclosure. 1-2 Weeks*
$77.50
1911-0 Differential pressure switch, SPDT, range .15 - .5" w.c. less conduit enclosure. 1-2 Weeks*
$72.50
1911-1 Differential pressure switch, SPDT, range .4 - 1.6" w.c. less conduit enclosure. 1-2 Weeks*
$72.50
1911-5 Differential pressure switch, SPDT, range 1.4 - 5.5" w.c. less conduit enclosure. 1-2 Weeks*
$72.50
1911-10 Differential pressure switch, SPDT, range 3 - 11" w.c. less conduit enclosure. 1-2 Weeks*
$72.50
1911-20 Differential pressure switch, SPDT, range 4 - 20" w.c. less conduit enclosure. 1-2 Weeks*
$72.50
1920-00 Differential pressure switch, SPDT, range .07 - .15" w.c. with threaded back connections. 1-2 Weeks*
$99.00
1920-0 Differential pressure switch, SPDT, range .15-.5" w.c. with threaded back connections. 1-2 Weeks*
$97.00
1920-1 Differential pressure switch, SPDT, range .4 - 1.6" w.c. with threaded back connections. 1-2 Weeks*
$97.00
1920-20 Differential pressure switch, SPDT, range 4 - 20" w.c. with threaded back connections. 1-2 Weeks*
$97.00
1920-10 Differential pressure switch, SPDT, range 3 - 11" w.c. with threaded back connections. 1-2 Weeks*
$97.00
1921-0 Differential pressure switch, SPDT, range .15 - .5" w.c. with threaded back connections, less conduit enclosure. 1-2 Weeks*
$97.00
1921-00 Differential pressure switch, SPDT, range .07-.15" w.c. with threaded back connections, less conduit enclosure. 1-2 Weeks*
$99.00
1921-1 Differential pressure switch, SPDT, range .4-1.6" w.c. with threaded back connections, less conduit enclosure. 1-2 Weeks*
$97.00
1920-5 Differential pressure switch, SPDT, range 1.4 - 5.5" w.c. with threaded back connections. 1-2 Weeks*
$97.00
1921-5 Differential pressure switch, SPDT, range 1.4-5.5" w.c. with threaded back connections, less conduit enclosure. 1-2 Weeks*
$97.00
1921-10 Differential pressure switch, SPDT, range 3-11" w.c. with threaded back connections, less conduit enclosure. 1-2 Weeks*
$97.00
1921-20 Differential pressure switch, SPDT, range 4-20" w.c. with threaded back connections, less conduit enclosure. 1-2 Weeks*
$97.00

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).
Compliance:
CE, CSA, FM, UL. Optional EXPL Explosion-proof enclosure does not possess any agency approvals.
  • 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
  • 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.

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
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.
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
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.
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Model Description Availability* Price
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 1-3 days*
$11.75
A-329 1/8" NPT close coupled street ell, brass. 1-3 days*
$7.50
A-399 Duct pressure monitor kit, for use with standard or manual reset model switches. Less Than 1 Week*
$55.50
A-489 4" 303 SS straight static pressure tip with flange, 1/4" hose barb. 1-3 days*
$9.00