Series 1950G – Integral Explosion-Proof Pressure Switches
Specifications - Installation and Operating Instructions
Adjustment Screw
1/2˝ Female NPT
Electrical Conduit
Connection
Vent Drain
Plug
The MODEL 1950G Explosion-Proof Switch combines the best features of the popular
Series 1900 Pressure Switch with a compact explosion-proof housing.
This unit is UL, CSA, FM listed for use in Class I, Groups A*, B, C, D, Class II, Groups
E, F, & G and Class III atmospheres and Directive 2014/34/EU (ATEX) Compliant for
II 2G Ex d IIB + H2 T6 Gb. IECEx certified Ex d IIB + H2 T6 Gb (-40°C < Ta < +
60°C) units are available. It is also totally rain-tight for outdoor installations. Six models
allow set-points from 0.07 to 20 in w.c. (1.78 mm to 508.0 mm w.c.).
Easy access to the SPDT relay for electrical hook-up is provided by removing the top
plate of the aluminum housing. 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. The unit is very compact, about half the weight
and bulk of equivalent conventional explosion-proof switches.
Attention: Units with the "NA" suffix are not Directive 2014/34/EU (ATEX) compliant.
These units are not intended for use in potentially explosive atmospheres in the EU.
These units may be CE marked for other Directives of the EU.
*GR. A is
Only.
DWYER INSTRUMENTS, INC.
P.O. BOX 373 • MICHIGAN CITY, INDIANA 46360, U.S.A.
Set Point
External
Ground Screw
Captive
Screw
UL, CSA, FM Listed For
CL, I GR. A*, B, C, D - CL. II GR. E, F, G - CL. III
Directive 2014/34/EU (ATEX) Compliant For
0518
II 2G Ex d IIB + H
EC-Type Certificate Number: KEMA 03ATEX2402 X
ATEX Standards:
EN 60079-0:2012 + A11:2013
EN 60079-1:2007
IECEx Certified for:
Ex d IIB + H
T6 Gb (-40°C < Ta < +60°C)
2
IECEx Certificate of Conformity:
IECEx DEK 11.0092X
IECEx Standards:
IEC 60079-0:2011
IEC 60079-1:2007
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: IP54, NEMA 3, 7 and 9.
Switch Type: 1 Form C relay (SPDT).
Electrical Rating: 10A, 120/240 VAC, 28 VDC. Resistive 50mA, 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).
MODEL 1950G SWITCHES:
OPERATING RANGES AND DEADBANDS
Approximate Dead
Band
Operating
To order Specify
Range
At Min.
Model Number*
in w. c.
Set Point
1950G-00-B-__
0.07 to 0.15
0.04
1950G-0-B-__
0.15 to 0.5
0.06
1950G-1-B-__
0.4 to 1.6
0.11
1950G-5-B-__
1.4 to 5.5
0.4
1950G-10-B-__
3.0 to 11.0
0.9
1950G-20-B-__
4.0 to 20.0
1.2
*Specify either 24 for 24 VDC, 120 for 120 VAC or 240
for 240 VAC when ordering. Example: 1950G-00-B-120
*Add "NA" suffix for models with UL, CSA and FM
approvals only. Example: 1950G-00-B-120-NA
Phone: 219/879-8000
Fax: 219/872-9057
Bulletin E-57G
T6 Gb
2
At Max.
Set Point
0.06
0.11
0.29
0.9
1.8
3.0
www.dwyer-inst.com