Dwyer Instruments SERIES 1950 Data Sheet

SERIES 1950 | EXPLOSION-PROOF DIFFERENTIAL PRESSURE SWITCH

FEATURES/BENEFITS

• Explosion-proof and weatherproof housing provides device protection for outdoor use or harsh environment operation

• External set point screw provides easy access without opening or disassembling enclosure

•Easilyaccessibleelectricalconnectionsimpliestheinstallation

DESCRIPTIONAPPLICATIONS

• HVAC applications

• Process applications

• All-weather applications

The Series 1950 Explosion-Proof Differential Pressure Switch combines the best features of the popular Dwyer® Series 1900 Pressure Switch with an integral explosion-proof and weatherproof housing, making it an exceptional value for either application. It is CE, UL and CSA listed, FM approved for use in Class I, Div 1, Groups C and D, Class II Groups E, F, and G and Class III hazardous atmospheres NEMA 7 & 9. Rain tight NEMA 3 (IP54), weatherproof features include a drain plug and O-ring seal in cover. Electrical connections are easily made by removing front cover. For convenience the set point adjustment screw is located on the outside of the housing. Twelve models offer set points from .03 to 20 in w.c. (0.0075 to 5 kPa) and from .5 to 60 psi (0.035 to 3.5 bar). The unit is very light and compact - about half the weight and bulk of other explosion-proof or weatherproof switches with separate enclosures.

SPECIFICATIONS

Service Air and non-combustible, compatible gases.

Wetted Materials Consult factory.

Temperature Limits -40 to 140°F (-40 to 60°C); 0 to 140°F (-17.8 to 60°C) for 1950P-8, 15, 25, and 50. -30 to 130°F (-34.4 to 54.4°C)

for 1950-02.

Pressure Limits (Continuous) 1950’s - 45 in w.c. (0.11 bar); 1950P’s - 35 psi (2.41 bar); 1950P-50 only - 70 psi (4.83 bar). Surge: 1950’s - 10 psi

(0.69 bar), 1950P’s - 50 psi (3.45 bar), 1950P-50 only - 90 psi (6.21 bar).

Enclosure Rating NEMA 3 (IP54), NEMA 7 & 9.

Switch Type Single-pole double-throw (SPDT).

Electrical Rating 15 A @, 125, 250, 480 VAC, 60 Hz. Resistive 1/8 HP @ 125 VAC, 1/4 HP @ 250 VAC, 60 Hz.

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 on top of housing.

Weight 3.25 Ib (1.5 kg); 1950-02 model, 4.4 lb (2 kg).

Agency Approvals CE, CSA, FM, UL.

DIMENSIONS

HOLES EQUALL

1/8 FEMALE NPT

1-15/32 [37.30]

3-1/2 [88.90]

NOTE: 1950-02: 7-3/4˝ (196.9) DIA.

[2] Ø17/64 [6.75] MOUNTING

RANGE ADJUSTMENT SCREW

WIRING DIAGRAM

HOW TO ORDER

EXTERNAL

GROUND

Y SPACED ON

A 4-7/8 [123.83] B.C.

LOW PRESSURE CONNECTION

VENT DRAIN PLUG

5-7/16

[138.13]

CAPTIVE SCREW

1-23/32 [43.64]

3/8 [9.53]

27/32 [21.43]

27/32

[21.43]

3/8 [9.53]

X 4-11/32˝ (110.3) DEPTH. FOR COMPLETE DIMENSIONS REQUEST DRAWING 28-700175-00 FROM OUR CUSTOMER SERVICE DEPARTMENT

1/8 FEMALE NPT HIGH PRESSURE CONNECTION

1/2 FEMALE NPT ELECTRICAL CONNECTION

Use the bold characters from the chart below to construct a product code.

1950 -02 -2 S - AT

SWITCH TYPE

1950: Pressure switch - inches w.c. 1950P: Pressure switch - PSID

RANGE

-02: 0.03 - 0.10 in w.c.

-00: 0.07 - 0.15 in w.c.

-0: 0.15 - 0.5 in w.c.

-1: 0.4 - 1.6 in w.c.

-5: 1.4 - 5.5 in w.c.

-10: 3.0 - 11.0 in w.c.

-20: 4.0 - 20.0 in w.c.

-2: 0.5 - 2.0 psid

-8: 1.5 - 8.0 psid

-15: 3.0 - 15.0 psid

MICRO SWITCH TYPE

-2: 10G mica silver contact*

-6: 10G phenolic gold contact

-M: 10C phenolic silver contact

-25: 4.0 - 25.0 psid

-50: 15.0 - 50.0 psid

*The 2F is standard

OPTIONS

-AT: Aluminum tag

-PRESET: Preset

-ST: Stainless steel tag

DIAPHRAGM MATERIAL

B: Buna-N F: Flurosilicone* N: Neoprene S: Silicone V: Fluroelastomer

DWYER INSTRUMENTS, INC.

Important Notice: Dwyer Instruments, Inc. reserves the right to make changes to or discontinue any product or service identied in this publication without notice. Dwyer advises its customers to obtain the

latest version of the relevant information to verify, before placing any orders, that the information being relied upon is current.