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Series 1950 Explosion-proof Differential Pressure Switch

Series 1950G Explosion-Proof Differential Pressure Switch

Series DA/DS Bourdon Tube Pressure Switches

Pressure Ranges to 2500 psi (172.4 bar)

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Customers tell us that the Series DA/DS Bourdon Tube Pressure Switches are the best pressure switches made. The Mercoid DA/DS Series is one of the world’s broadest lines of pressure switches. The DA/DS Series has extremely high sensitivity and great repeatability. The DA Models are equipped with two external adjustments, one for setting high pressure operating point, the other for setting low pressure operating point. Deadband, the difference between high and low setpoints, is adjustable over the full-scale. The DS Models are equipped with a single external adjustment for setting operating point only. For mercury-free switches we offer the snap action switch. Hermetically sealed mercury switch also available.

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Product Applications

Compressors
Mechanical HVAC or process equipment
Pump control

Ordering

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SPDT Mercury Switch 4A @ 120V, 2A @ 240V, Adjust. Deadband

SPDT Snap Switch, Adjust. Deadband

SPDT Snap Switch, Fixed Deadband

SPST NC Mercury Switch 10A @ 120V, 5A @ 240V, Adjust. Deadband

Grouped product items
Model	Description	Availability*	Price
DA-21-153-11S	Pressure switch, 403SS Bourdon tube, range 50-1000 psig, 60 psig min. deadband.	1-2 Weeks*	$1,844.95
DA-21-153-12S	Pressure switch, 403SS Bourdon tube, range 100-1500 psig, 90 psig min. deadband.	1-2 Weeks*	$1,976.00
DA-21-153-13S	Pressure switch, 403SS Bourdon tube, range 300-2500 psig, 150 psig min. deadband.	1-2 Weeks*	$1,976.00
DA-21-153-15S	Pressure switch, 403SS Bourdon tube, range 500-5000 psig, 450 psig min. deadband.	1-2 Weeks*	$1,997.85
DA-21-153-25S	Pressure switch, 403SS Bourdon tube, range 30" Hg Vac-60 psig, 6 psig min. deadband.	Call for Details*	$1,306.25
DA-21-153-26S	Pressure switch, 403SS Bourdon tube, range 30" Hg Vac-75 psig, 8 psig min. deadband.	1-2 Weeks*	$1,306.25
DA-21-153-5S	Pressure switch, 403SS Bourdon tube, range 2-60 psig, 4 psig min. deadband.	1-2 Weeks*	$1,306.25
DA-21-153-6S	Pressure switch, 403SS Bourdon tube, range 5-100 psig, 6 psig min. deadband.	Call for Details*	$1,306.25
DA-21-153-8S	Pressure switch, 403SS Bourdon tube, range 10-200 psig, 8 psig min. deadband.	1-2 Weeks*	$1,306.25
DA-21-153-9AS	Pressure switch, 403SS Bourdon tube, range 40-350 psig, 14 psig min. deadband.	1-3 days*	$1,470.55
DA-21-153-9S	Pressure switch, 403SS Bourdon tube, range 10-300 psig, 14 psig min. deadband.	1-2 Weeks*	$1,395.70
DA-31-153-1	Pressure switch, brass Bourdon tube, range 1/8-15 psig, 1 psig min. deadband.	1-2 Weeks*	$979.70
DA-31-153-2	Pressure switch, brass Bourdon tube, range 30-0" Hg Vac, 2" Hg min. deadband.	1-2 Weeks*	$979.70
DA-31-153-27	Pressure switch, brass Bourdon tube, range 25" Hg Vac-50 psig, 3.5 psig min. deadband.	1-2 Weeks*	$979.70
DA-31-153-3	Pressure switch, brass Bourdon tube, range 10" Hg Vac-12 psig, 1 psig min. deadband.	1-2 Weeks*	$979.70
DA-31-153-3A	Pressure switch, brass Bourdon tube, range 1/8-20 psig, 1 psig min. deadband.	1-2 Weeks*	$979.70
DA-31-153-4	Pressure switch, brass Bourdon tube, range 1-35 psig, 1.75 psig min. deadband.	1-2 Weeks*	$979.70
DA-31-153-5	Pressure switch, brass Bourdon tube, range 2-60 psig, 3 psig min. deadband.	1-2 Weeks*	$979.70
DA-31-153-6	Pressure switch, brass Bourdon tube, range 5-100 psig, 3.75 psig min. deadband.	1-3 days*	$979.70
DA-31-153-7	Pressure switch, brass Bourdon tube, range 5-150 psig, 6 psig min. deadband.	1-3 days*	$979.70
DA-31-153-8	Pressure switch, brass Bourdon tube, range 10-200 psig, 8 psig min. deadband.	1-3 days*	$1,082.65
DA-31-153-9	Pressure switch, brass Bourdon tube, range 10-300 psig, 12 psig min. deadband.	1-3 days*	$1,082.65
DA-41-153-11E	Pressure switch, 316SS Bourdon tube, range 100-1000 psig, 100 psig min. deadband.	1-2 Weeks*	$1,976.00
DA-41-153-13E	Pressure switch, 316SS Bourdon tube, range 200-2500 psig, 210 psig min. deadband.	1-2 Weeks*	$1,976.00
DA-41-153-21E	Pressure switch, 316SS Bourdon tube, range 30-400 psig, 30 psig min. deadband.	1-2 Weeks*	$1,521.50
DA-41-153-22E	Pressure switch, 316SS Bourdon tube, range 75-800 psig, 75 psig min. deadband.	1-2 Weeks*	$1,725.35
DA-41-153-23E	Pressure switch, 316SS Bourdon tube, range 5-75 psig, 3 psig min. deadband.	1-2 Weeks*	$1,395.70
DA-41-153-24E	Pressure switch, 316SS Bourdon tube, range 10-150 psig, 6 psig min. deadband.	1-2 Weeks*	$1,395.70
DA-41-153-26E	Pressure switch, 316SS Bourdon tube, range 30" Hg Vac-75 psig, 7 psig min. deadband.	1-2 Weeks*	$1,395.70
DA-41-153-6E	Pressure switch, 316SS Bourdon tube, range 10-100 psig, 7 psig min. deadband.	1-2 Weeks*	$1,395.70
DA-41-153-9E	Pressure switch, 316SS Bourdon tube, range 10-300 psig, 18 psig min. deadband.	1-2 Weeks*	$1,449.75
DA-41-2-11E	Pressure switch, 316SS Bourdon tube, range 100-1000 psig, 100 psig min. deadband.	1-2 Weeks*	$1,976.00
DA-41-2-13E	Pressure switch, 316SS Bourdon tube, range 200-2500 psig, 210 psig min. deadband.	1-2 Weeks*	$1,976.00
DA-41-2-21E	Pressure switch, 316SS Bourdon tube, range 30-400 psig, 30 psig min. deadband.	1-2 Weeks*	$1,521.50
DA-41-2-23E	Pressure switch, 316SS Bourdon tube, range 5-75 psig, 3 psig min. deadband.	1-2 Weeks*	$1,395.70
DA-41-2-24E	Pressure switch, 316SS Bourdon tube, range 10-150 psig, 6 psig min. deadband.	1-2 Weeks*	$1,395.70
DA-41-2-26E	Pressure switch, 316SS Bourdon tube, range 30" Hg Vac-75 psig, 7 psig min. deadband.	1-2 Weeks*	$1,395.70
DA-41-2-6E	Pressure switch, 316SS Bourdon tube, range 10-100 psig, 7 psig min. deadband.	1-2 Weeks*	$1,395.70
DA-41-2-9E	Pressure switch, 316SS Bourdon tube, range 10-300 psig, 18 psig min. deadband.	1-2 Weeks*	$1,449.75
DA-7021-153-10S	Pressure switch, 403SS Bourdon tube, range 25-600 psig, 67.5 psig min. deadband.	1-2 Weeks*	$1,381.10
DA-7021-153-11S	Pressure switch, 403SS Bourdon tube, range 50-1000 psig, 142.5 psig min. deadband.	1-2 Weeks*	$1,734.70
DA-7021-153-12S	Pressure switch, 403SS Bourdon tube, range 100-1500 psig, 195 psig min. deadband.	1-2 Weeks*	$1,839.75
DA-7021-153-13S	Pressure switch, 403SS Bourdon tube, range 300-2500 psig, 390 psig min. deadband.	1-2 Weeks*	$1,839.75
DA-7021-153-15S	Pressure switch, 403SS Bourdon tube, range 500-5000 psig, 1350 psig min. deadband.	1-2 Weeks*	$1,874.10
DA-7021-153-25S	Pressure switch, 403SS Bourdon tube, range 30" Hg Vac-60 psig, 18 psig min. deadband.	Call for Details*	$1,210.55
DA-7021-153-26S	Pressure switch, 403SS Bourdon tube, range 30" Hg Vac-75 psig, 22.5 psig min. deadband.	1-2 Weeks*	$1,210.55
DA-7021-153-5S	Pressure switch, 403SS Bourdon tube, range 2-60 psig, 13.5 psig min. deadband.	1-2 Weeks*	$1,210.55
DA-7021-153-6S	Pressure switch, 403SS Bourdon tube, range 5-100 psig, 19.5 psig min. deadband.	Call for Details*	$1,210.55
DA-7021-153-8S	Pressure switch, 403SS Bourdon tube, range 10-200 psig, 22.5 psig min. deadband.	1-2 Weeks*	$1,210.55
DA-7021-153-9AS	Pressure switch, 403SS Bourdon tube, range 40-350 psig, 30 psig min. deadband.	1-2 Weeks*	$1,381.10
DA-7021-153-9S	Pressure switch, 403SS Bourdon tube, range 10-300 psig, 28.5 psig min. deadband.	1-2 Weeks*	$1,381.10
DA-7031-153-1	Pressure switch, brass Bourdon tube, range 1/8-15 psig, 6 psig min. deadband.	1-2 Weeks*	$903.75
DA-7031-153-2	Pressure switch, brass Bourdon tube, range 30-0" Hg Vac, 13.5" Hg min. deadband.	1-2 Weeks*	$903.75
DA-7031-153-27	Pressure switch, brass Bourdon tube, range 25" Hg Vac-50 psig, 12 psig min. deadband.	1-2 Weeks*	$903.75
DA-7031-153-3	Pressure switch, brass Bourdon tube, range 10" Hg Vac-12 psig, 6 psig min. deadband.	1-2 Weeks*	$903.75
DA-7031-153-3A	Pressure switch, brass Bourdon tube, range 1/8-20 psig, 6 psig min. deadband.	1-2 Weeks*	$903.75
DA-7031-153-4	Pressure switch, brass Bourdon tube, range 1-35 psig, 7.5 psig min. deadband.	1-2 Weeks*	$903.75
DA-7031-153-5	Pressure switch, brass Bourdon tube, range 2-60 psig, 9 psig min. deadband.	1-3 days*	$903.75
DA-7031-153-6	Pressure switch, brass Bourdon tube, range 5-100 psig, 13.5 psig min. deadband.	1-2 Weeks*	$903.75
DA-7031-153-7	Pressure switch, brass Bourdon tube, range 5-150 psig, 24 psig min. deadband.	1-3 days*	$903.75
DA-7031-153-8	Pressure switch, brass Bourdon tube, range 10-200 psig, 24 psig min. deadband.	1-3 days*	$995.30
DA-7031-153-9	Pressure switch, brass Bourdon tube, range 10-300 psig, 37.5 psig min. deadband.	1-3 days*	$995.30
DA-7041-153-13E	Pressure switch, 316SS Bourdon tube, range 200-2500 psig, 600 psig min. deadband.	1-2 Weeks*	$1,837.70
DA-7041-153-21E	Pressure switch, 316SS Bourdon tube, range 30-400 psig, 78 psig min. deadband.	1-2 Weeks*	$1,440.40
DA-7041-153-22E	Pressure switch, 316SS Bourdon tube, range 75-800 psig, 180 psig min. deadband.	1-2 Weeks*	$1,620.30
DA-7041-153-23E	Pressure switch, 316SS Bourdon tube, range 5-75 psig, 12 psig min. deadband.	1-2 Weeks*	$1,313.50
DA-7041-153-24E	Pressure switch, 316SS Bourdon tube, range 10-150 psig, 16.5 psig min. deadband.	1-2 Weeks*	$1,313.50
DA-7041-153-26E	Pressure switch, 316SS Bourdon tube, range 30" Hg Vac-75 psig, 15 psig min. deadband.	1-2 Weeks*	$1,313.50
DA-7041-153-6E	Pressure switch, 316SS Bourdon tube, range 10-100 psig, 15 psig min. deadband.	1-2 Weeks*	$1,313.50
DA-7041-153-9E	Pressure switch, 316SS Bourdon tube, range 10-300 psig, 42 psig min. deadband.	1-2 Weeks*	$1,313.50
DS-7231-153-1	Pressure switch, brass Bourdon tube, range 1/8-15 psig, 1.5 psig fixed deadband.	1-2 Weeks*	$903.75
DS-7231-153-2	Pressure switch, brass Bourdon tube, range 30-0" Hg Vac, 3" Hg fixed deadband.	1-2 Weeks*	$903.75
DS-7231-153-3	Pressure switch, brass Bourdon tube, range 10" Hg Vac-12 psig, 1.5 psig fixed deadband.	1-2 Weeks*	$903.75
DS-7231-153-3A	Pressure switch, brass Bourdon tube, range 1/8-20 psig, 1.5 psig fixed deadband.	1-2 Weeks*	$903.75
DS-7231-153-4	Pressure switch, brass Bourdon tube, range 1-35 psig, 1.5 psig fixed deadband.	1-2 Weeks*	$903.75
DS-7231-153-5	Pressure switch, brass Bourdon tube, range 2-60 psig, 2 psig fixed deadband.	1-2 Weeks*	$903.75
DS-7231-153-6	Pressure switch, brass Bourdon tube, range 5-100 psig, 2.5 psig fixed deadband.	1-2 Weeks*	$903.75
DS-7231-153-7	Pressure switch, brass Bourdon tube, range 5-150 psig, 3 psig fixed deadband.	1-2 Weeks*	$903.75
DS-7231-153-8	Pressure switch, brass Bourdon tube, range 10-200 psig, 4 psig fixed deadband.	1-2 Weeks*	$995.30
DA-21-153-10S	Pressure switch, 403SS Bourdon tube, range 25-600 psig, 25 psig min. deadband.	1-2 Weeks*	$1,470.55
DS-7231-153-9	Pressure switch, brass Bourdon tube, range 10-300 psig, 5 psig fixed deadband.	1-2 Weeks*	$995.30

Specifications

Wetted Materials:: Brass, 403 SS, or 316 SS.
Temperature Limit:: 180°F (82°C).
Pressure Limit:: Maximum pressure of the operating range.
Enclosure Rating:: General purpose, weatherproof or explosion-proof.
Repeatability:: ±1% of full operating range, ±1.5% on DS-7300 models.
Switch Type:: SPST mercury switch, SPDT mercury switch, SPDT snap switch.
Electrical Rating:: See Catalog page.
Electrical Connections:: Screw terminal.
Conduit Connection:: General purpose: 1/2" hole for conduit hub. Weatherproof: 1/2" conduit hub. Explosion-proof: 3/4" female NPT.
Process Connection:: General purpose and weatherproof: 1/4" male NPT; 1/2" male NPT on range 15S and 16S. Explosion-proof: 1/2" male NPT and 1/4" female NPT.
Mounting Orientation:: Vertical.
Set Point Adjustment:: Thumbscrew.
Weight:: General purpose: 4 lb (1.8 kg). Weatherproof: 6 lb (2.7 kg). Explosion-proof: 8 lb (3.5 kg).
Deadband:: See Catalog page.
Compliance:: CSA, FM, UL. (Consult factory for FM approval models.)

Features

Visible calibrated dial provides an easy and fast check without having to open device causing dangerous conditions to operators
On/off indication (except hermetically sealed snap switch models) gives operator clear indication of state of switched equipment that could be located in another location
Adjustable or fixed deadband supports control applications by reducing equipment wear-out by unnecessary recycling
External switch setpoint adjustments reduces set-up time
Pressure ranges of full vacuum to 8000 psig gives application designers the ability to specify standard equipment, simplifying install and training, and reducing servicing costs
UL listed, CSA approved many models FM approved to support rigorous process applications and regulations
General purpose, weatherproof or explosion-proof enclosures for a variety of indoor or outdoor environments meeting the needs of multiple applications and uses

Options

Explosion-proof Enclosure (Series DAH): Suitable for Class I, Groups C and D; NEMA 7; Class II, Groups E, F, G; Class III NEMA 9 and 9A, Division 1. Add "H" to model number after DA or DS. Example: DAH-31-153-7.
FM Approved: For general purpose and explosion-proof models see Agency Approvals on Specification page. Add "F" to model number after DA, DS, DAH or DSH. Examples: DAF-31-153-7 or DAHF-31-153-7.
Other Options (consult factory): DPDT switches or other switch types, fixed deadband mercury switch units for low deadband applications, manual reset operation, two-stage operation, acetal bushed movement for applications with high amounts of vibration and/or pulsation, fungus proofing, siphon, diaphragm seals, mounting flange and remote connection.
Weatherproof Enclosure (Series DAW): Add "W" to model number after DA or DS and change 1 to 3. Example: DAW-33-153-7.

Support Library

Product Literature

Manuals

Catalog Pages

Series DA/DS Catalog Page

SDS

Mercury Switch

Approvals

Drawings

Videos

FAQ

Questions

Question

I am trying to buy a replacement part for a mercoid pressure switch. The part number given on the device is DA-31-153 RG 9. What does the "RG" stand for? Is buying the DA-31-153-9 an equivalent part? Thank you in advance.

Answer

RG stands for Range. In this case, RG 9 means Range 9. You full model number is DA-31-153-9.

Related

Series DA/DS

Question

Could you please submit to us if the pressure switch model #DA-21-2-9S still produces? and if it became obsolete what is the direct replacement or equivalent pressure switch type?

Answer

Yes, we still offer the DA-21-2-9S pressure gage.

Related

Series DA/DS

Reviews

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Accessories

Model	Description	Availability*	Price
49-62HP	Remote connection, 6 ft. copper, 2500 psig max.	1-2 Weeks*	$199.70
49-210	Remote connection, 12 ft. 316SS, 3000 psig max.	1-2 Weeks*	$488.80
42-52	Pigtail siphon, 250 psig max.	1-2 Weeks*	$143.50
33-25	Mounting bracket.	1-2 Weeks*	$78.50