Dwyer Instruments SERIES H3 Catalog Page

COVER

CONNECTION

[101.6]

SERIES H3 | W. E. ANDERSON™ BY DWYER

EXPLOSION-PROOF DIFFERENTIAL PRESSURE SWITCH

Set points from 10 in w.c. to 200 psid, Rated 1500 psig, Weatherproof

PRESSURE

Internal terminal blocks for conductors up to 18 gage are optional

Optional NEMA 3 (lP54) enclosure includes explosion-proof drain; Standard NEMA 4X (IP56) version is without drain

External ground connection standard

Shown without

enclosure and cover

(internal ground connection also standard, use either one)

SET SCREW

3/4 NPT

CONDUIT

5-3/8

[136.53]

OPTIONAL DRAIN

[24.61]

PROCESS

CONNECTION

CENTERLINE

31/32

2-13/32

[61.12]

3-9/16 [90.49]

COVER

Ø11/64 [Ø4.37] MOUNTING HOLES IN MTG BRACKET

1-25/32

[45.24]

LOW PRESSURE

CONNECTION

17/32 [13.5]

HIGH PRESSURE

CONNECTION

1/8 NPT

[762]

1-3/4

[44.45]

The Series H3 Explosion-Proof Differential Pressure Switch is a heavy duty, industrial unit with a unique new design which provides sensitivity to differential pressures as low as 10 inches of water (254 mm w.c.), yet handles total pressure of 1500 psi (103 bar). Unlike common differential pressure switches that use a pistontype motion transfer, the Series H3 utilizes a rotary motion transfer shaft that prevents a change in total pressure from causing a set point shift. Unit yields deadbands approximately 5% of range, with zero set point shift due to variation in working pressures. Friction is minimized and repeatability increased by allowing range spring to act directly on diaphragm plate. Rolling diaphragm design maintains constant effective area to further reduce friction. Diaphragm is allowed to “seat”, allowing application of full rated pressure, up to 1500 psi (103 bar), on either high or low pressure port, without damage. Special over-travel feature prevents overtightening of range adjust

screw. Choose optional 316 SS chamber for water and water-based uids or harsher

applications.

FEATURES/BENEFITS

• Rotary motion design prevents set point shifts

• Explosion-proof housing for use in applications where protection of process and personnel is needed

• Option for use with water and water-based solution makes this a versatile switch

APPLICATIONS

• Water ow proving with an orice plate

• Differential pressure across chiller

• Liquid lter status

Differential Pressure Switches

MODEL CHART Example H3 S -2 S C -MV H3S-2SC-MV Series H3 Explosion-proof differential pressure switch Pressure Chamber and

Diaphragm Material (Wetted)AS Adjustable Operating Range 1

Circuit (Switch) Options S

Electrical Connection L

Options Drain

HAZARDOUS LOCATION RATINGS Model UL CSA Directive 2014/34/EU ATEX Compliant H3 _ – _ _ C

H3 _ – _ _ L

H3 _ – _ _ T

H3 _ – _ _ C-DRAIN

H3 _ – _ _ L-DRAIN

DWYER INSTRUMENTS, INC. 56

CI. I, Gr.B, C & D CI. II, Gr.E, F & G CI. I, Gr.B, C & D CI. II, Gr.E, F & G

CI. I, Gr.B, C & D CI. II, Gr.E, F & G

2 3 4

T C

VIT

CI. I, Gr.B, C & D CI. II, Gr.E, F & G CI. I, Gr.B, C & D CI. II, Gr.E, F & G

SPECIFICATIONS Wetted Materials: See pressure chamber and diaphragm material in model chart.

Temperature Limit: -4 to 220°F (-20 to 104°C), ATEX: -20 to 90°C (-4 to 194°F). Pressure Limit: 1500 psig (103 bar). Enclosure Rating:

(IP54). For hazardous use see the hazardous location ratings chart.

Switch Type: SPDT or DPDT snap switch. Electrical Rating: 5 A @ 125/250 VAC, 30 VDC. Electrical Connections: See model chart. Conduit Connection: 3/4˝ female NPT. Process Connection: 1/8˝ female NPT. Mounting Orientation: Vertical. Set Point Adjustment: Internal screw. Weight: 4 lb 2 oz (2 kg). Deadband: Approximately 5% of range. Agency Approvals: ATEX, CE, CSA, UL see ratings chart.

Aluminum chamber with nitrile diaphragm

316 SS chamber with uoroelastomer diaphragm

10-180 in. w.c. (2.48-44.78 kPa)

0.5-15 psid (0.03-1 bar) 5-70 psid (.34-4.8 bar) 10-200 psid (.7-13.8 bar)

SPDT snap action switch rated 5 A @ 125/250 VAC, 30 VDC DPDT snap action switch rated 5 A @ 125/250 VAC, 30 VDC

18 AWG x 18 inch lead wires UL, CSA approved internal terminal block ATEX approved internal terminal block

Enclosure with drain - allows condensate to be drained from inside (meets NEMA 3 instead of 4X) Gold contacts on snap switch for dry circuits rated 1 A @ 125 VAC, 1A resistive or 0.5 A inductive @ 30 VDC Fluoroelastomer diaphragm option where not standard

2813 II 2 G Ex d IIC T5 or T6 EC-Type

Certicate No. KEMA 03ATEX 2584

2813 II 2 G Ex d IIC T5 or T6 EC-Type

Certicate No. KEMA 03ATEX 2584

Standard meets NEMA 4X (IP56), drain option meets NEMA 3

ACCESSORIES Model Description A-610 Pipe mounting kit for 1-1/4 to 2˝ pipe