Product Overview

55
Differential Pressure Switches
PRESSURE
DWYER INSTRUMENTS, INC. | dwyer-inst.com
EXPLOSION-PROOF DIFFERENTIAL PRESSURE SWITCH
Compact, Low Cost, Explosion-proof and Weatherproof
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.
CAUTION: For use only with air or compatible gases. Applications with hazardous
atmospheres and a single positive pressure may require special venting.
FEATURES/BENEFITS
• Explosion-proof and weatherproof housing provides device protection for outdoor
use or harsh environment operation
• Externalsetpointscrewprovideseasyaccessthatsimpliesmakingadjustments
without opening or disassembling enclosure
• Easilyaccessibleelectricalconnectionsimpliestheinstallation
APPLICATIONS
• HVAC applications • Process applications • All-weather applications
EXTERNAL
GROUND
[2] Ø17/64 [6.75] MOUNTING
HOLES EQUALL
Y SPACED ON
A 4-7/8 [123.83] B.C.
RANGE
ADJUSTMENT SCREW
5-7/16
[138.13]
1/2 FEMALE NPT
ELECTRICAL CONNECTION
VENT DRAIN
PLUG
CAPTIVE SCREW
1/8 FEMALE NPT
LOW PRESSURE CONNECTION
1-15/32 [37.30]
3/8 [9.53]
27/32 [21.43]
27/32
[21.43]
3-1/2 [88.90]
1-23/32 [43.64]
3/8 [9.53]
1/8 FEMALE NPT HIGH
PRESSURE CONNECTION
NOTE: 1950-02: 7-3/4˝ (196.9) DIA.
X 4-11/32˝ (110.3) DEPTH. FOR
COMPLETE DIMENSIONS REQUEST
DRAWING 28-700175-00 FROM
OUR CUSTOMER SERVICE
DEPARTMENT
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.
EXTERNAL
GROUND
[2] Ø17/64 [6.75] MOUNTING
HOLES EQUALL
Y SPACED ON
A 4-7/8 [123.83] B.C.
RANGE
ADJUSTMENT SCREW
5-7/16
[138.13]
1/2 FEMALE NPT
ELECTRICAL CONNECTION
VENT DRAIN
PLUG
CAPTIVE SCREW
1/8 FEMALE NPT
LOW PRESSURE CONNECTION
1-15/32 [37.30]
3/8 [9.53]
27/32 [21.43]
27/32
[21.43]
3-1/2 [88.90]
1-23/32 [43.64]
3/8 [9.53]
1/8 FEMALE NPT HIGH
PRESSURE CONNECTION
NOTE: 1950-02: 7-3/4˝ (196.9) DIA.
X 4-11/32˝ (110.3) DEPTH. FOR
COMPLETE DIMENSIONS REQUEST
DRAWING 28-700175-00 FROM
OUR CUSTOMER SERVICE
DEPARTMENT
SPECIFICATIONS
Service: Air and compatible combustible
gases.
Wetted Materials: Contact factory.
Temperature Limits: 0 to 140°F
(-17 to 60°C). Note: Set point drift
may occur with ambient temperature
changes.
Pressure Limits: 45 in w.c. (11.2 kPa)
continuous; 10 psig (68.95 kPa) surge.
Enclosure Rating: NEMA 3 (IP54),
NEMA 7 & 9.
Switch Type: 1 Form C relay (SPDT).
Electrical Rating: 10 A, 120/240 VAC,
28 VDC. Resistive 50 mA, 125 VDC.
Power Requirements: 24 VDC ±10%.
120 or 240 VAC ±10% optional.
Electrical Connections: Internal
terminal block.
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: 2 lb 15.7 oz (1.35 kg).
Agency Approvals: ATEX, CE, CSA,
FM, IECEx, UL.
Series 1950G Explosion-Proof Differential Pressure Switch combines the best
features of the popular Dwyer
®
Series1950PressureSwitchwiththebenetofnatural
gas compatibility. Units are rain-tight for outdoor installations, and are UL listed for use
in Class I, Groups A, B, C, & D; Class II, Groups E, F, & G and Class III atmospheres,
Directive 2014/34/EU (ATEX) Compliant for II 2G Exd IIB+H2 T6, CSA & FM
approved for Class I, Div. 1, Groups B, C, D; Class II, Div. 1, Groups E, F, G and Class
III atmospheres IECEx Ex d IIB+H2 T6 (-40°C < Ta < +60°C). The 1950G is very
compact, about half the weight and bulk of equivalent conventional explosion-proof
switches.
Easy access to the SPDT relay and power supply terminals is provided by removing
the top plate of the aluminum housing. A supply voltage of 24 VDC, 120 or 240 VAC
is required. A captive screw allows the cover to swing aside while remaining attached
to the unit. Adjustment to the set point of the switch can be made without disassembly
of the housing.
FEATURES/BENEFITS
• Compatible with natural gas making it suitable for use in those
applications
• Externalsetpointscrewprovideseasyaccessthatsimplies
making adjustments without opening or disassembling enclosure
• Easilyaccessibleelectricalconnectionsimpliestheinstallation
APPLICATIONS
• Natural gas applications
• Process applications
• All-weather applications
EXPLOSION-PROOF DIFFERENTIAL PRESSURE SWITCH
Explosion-proof, Weatherproof, Compatible with Natural Gases
SERIES 1950G
SERIES 1950
MODEL CHART
Model
Range,
psid
Approximate
Deadband
Model* Range*
Approximate
Deadband
Model
Range,
in w.c.
Approximate
Deadband
Min.
Set Point
Max.
Set Point
Min.
Set Point
Max.
Set Point
Min.
Set Point
Max.
Set Point
1950P-2-2F
1950P-8-2F
1950P-15-2F
1950P-25-2F
0.5 to 2
1.5 to 8
3 to 15
4 to 25
0.3
1.0
0.9
0.7
0.3
1.0
0.9
0.7
1950P-50-2F
1950-02-2S
1950-00-2F
1950-0-2F
15 to 50
.03 to .10
.07 to .15
.15 to .50
1.0
.025
.04
.10
1.5
.05
.05
.15
1950-1-2F
1950-5-2F
1950-10-2F
1950-20-2F
.4 to 1.6
1.4 to 5.5
3 to 11
4 to 20
.15
.30
.40
.40
.20
.40
.50
.60
*P=PSID range models. Other ranges in w.c.
Caution: For use only with air or compatible gases. Applications with hazardous atmospheres and a single positive pressure may require special venting.
MODEL CHART
UL, CSA, FM
Model
ATEX
Model
Range
in w.c.
Approximate Deadband
Min. Set Point Max. Set Point
1950G-00-B-24-NA
1950G-0-B-24-NA
1950G-1-B-24-NA
1950G-5-B-24-NA
1950G-10-B-24-NA
1950G-20-B-24-NA
1950G-00-B-24
1950G-0-B-24
1950G-1-B-24
1950G-5-B-24
1950G-10-B-24
1950G-20-B-24
.07 to .15
.15 to .50
.4 to 1.6
1.4 to 5.5
3 to 11
4 to 20
.04
.06
.11
.4
.9
1.2
.06
.11
.29
.9
1.8
3.0
240 VAC Models: 1950G-XX-B-240-NA; 120 VAC Models: 1950G-XX-B-120-NA
Pressure_2021.indb 55 7/15/20 8:18 AM