Compact Low Differential Pressure Switches- Series 1900
Our smallest, lowest cost precision switches. Six standard ranges Set points from 0.07" to 20" W.C. Repetitive accuracy within 3%
One of our most popular 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 in. W.C. Set point adjustment is easy with range screw located inside conduit enclosure. Internal location helps prevent tampering.
A-389 Mounting bracket (optional) is 16 ga. steel, zinc plated, dichromate dipped for corrosion resistance. Provides rugged, permanent mounting and speeds installation.
Environmental (MIL) Construction. Unlisted Model 1820 can be furnished with a special snap switch sealed against the environment for high humidity, exposure to fungus, and/or for military applications. Similar to Model 1823 except dead band is slightly greater and some lower set points may not be available. Specify Model 1820--(Range No.)--"MIL" and required set point in ordering
Weatherproof housing 16-ga. steel enclosure for unusually wet or oily conditions. Withstands 200 hour salt spray test. Gasketed cover. Wt. 51/2 Ibs. Switch must be in- stalled at factory. Specify "WP" after model number. Rated NEMA4.
Explosion-proof Housing Cast iron base with aluminum cover. Wt. 71/2 Ibs. Switch must be installed at factory. Specify suffix EXPL after model number. Rated NEMA 7&9; CI I, GrD, CI II,GroupsE,F8G,CI III.
1900-5-MR DUCT PRESSURE KIT includes special 1.4-5.5" W.C. range 1900 pressure switch with manual reset snap switch. Prevents-duct blowout by shutting down blower when excess pressure occurs. Won't allow start-up again until condition is corrected and switch is manually reset. Includes switch, duct pressure sensor tubing & adapters.
MANUAL RESET MODEL 1900 MR includes special snap switch which latches on pressure increase above set point. Must be manually reset after pressure drops below set point. To order, change model to 1900 and add MR suffix after range number. Example 1900-10-MR. Available on -1, -5, -10 or -20 ranges only. Not U.L., C.S.A. or F.M. Iisted.
P/N A-329 ALUMINUM STREET ELL simplifies installations requiring right angle connections. Two required for differential pressures.
Weatherproof Enclosure
16-ga. steel enclosure for unusually wet or oily conditions. Withstands 200 hour salt spray test. Gasketed cover. Wt. 5 Ibs. Switch must be installed at factory. Specify suffix WP after modelnumber. Rated NEMA 4.
Explosion-Proof Housing
Cast iron base with aluminum cover. Wt. 7 Ibs.Specify EXPL after model number.
Rated NEMA 7 & 9; Cl l, Gr D, Cl ll,Groups E, F & G, Cl lll.
| Temperature limits: | -30°F for dry air or gas to 180°F. |
|---|---|
| Maximum surface pressure: | 10 psig. |
| Rated pressure: | 45" H20 |
| Pressure connections: | 1/8" NPT. |
| Electrical rating: | 15 amps, 120-480 volts, 60 Hz. A.C. Resistive 1/8 H.P. @ 125 volts, 1/4 H.P. @ 250 volts, 60 Hz. A.C. Derate to 10 amps for operation at high cycle rates. |
| Wiring connections: | 3 screw type, common, normally open and normally closed. |
| Set point adjustment: | Screw type inside conduit enclosure. |
| Housing: | Aluminum die casting with chemical conversion coating for corrosion protection; zinc plated steel stamping. |
| Diaphragm: | Molded Silicone rubber. Aluminum diaphragm plate. |
| Calibration spring: | Stainless steel. |
| Weight: | 1 lb. |
| Installation: | Diaphragm vertical. |
CAUTION: FOR USE ONLY WITH AIR OR COMPATIBLE GASES.
| Model Number |
Operating Range Inches, W.C. |
Approximate Dead Band |
|
|---|---|---|---|
| At Min. Set Point |
At Max. Set Point |
||
| 1910-00 1910-0 1910-1 1910-5 1910-10 1910-20 |
0.07 to 0.15 0.15 to 0.55 0.4 to 1.75 1.4 to 55 3.0 to 11.75 4.0 to 20.0 |
.04 0.10 0.15 0.3 0.4 0.4 |
.04 0.10 0.16 0.30 0.40 0.50 |
SUGGESTED SPECIFICATIONS
Differential pressure switches shall be diaphragm operated with 3 1/2" diaphragm to actuate a single pole double throw snap switch. Motion of the diaphragm shall be restrained by a calibrated spring that can be adjusted to set the exact pressure differential at which the electrical switch will be actuated. Motion of the diaphragm shall be transmitted to the switch button by means of a direct mechanical linkage. Switches shall be Dwyer Instruments, Inc. Catalog No. 1910- for the required operating ranges.