Series DA/DS Bourdon Tube Pressure Switches
Pressure Ranges to 8000 psi (551.6 bar)
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, choose between the snap action switch or hermetically sealed snap action switch. Hermetically sealed mercury switch also available.
Product Applications
- Compressors
- Mechanical HVAC or process equipment
- Pump control
Models & Ordering
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.
- Agency Approvals:
- 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.
Accessories
Model Number | Description | Usually Ships* | Price | Order | |
---|---|---|---|---|---|
![]() |
33-25 | Mounting bracket. | 1-2 Weeks | $68.00 | Order |
![]() |
42-52 | Pigtail siphon, 250 psig max. | 1-2 Weeks | $124.00 | Order |
![]() |
49-62HP | Remote connection, 6 ft. copper, 2500 psig max. | 1-2 Weeks | $173.00 | Order |
![]() |
49-210 | Remote connection, 12 ft. 316SS, 3000 psig max. | 1-2 Weeks | $425.00 | Order |
Videos
Model Chart
EXAMPLE | _ _DA_ _ | _ _31 | _153_ _ | _4 | Standard DA Bourdon Tube Control, dual setpoint, automatic reset, SPDT mercury switch, 1-35 psig | |
RESET OPTIONS |
R | U | Manual reset, single adjustment, operates on decrease automatically | G E N E R A L |
||
R | L | Manual reset, single adjustment, operates on increase automatically | ||||
S(3) | Automatic reset, single adjustment, DS only | |||||
HOUSING & APPROVAL OPTIONS |
W | Weatherproof enclosure, NEMA 3S, 4 and 4X, flanged back standard | ||||
N3 W | Weather resistance, includes drain, flanged back standard, available as special order only | |||||
H | Explosion-proof enclosure, control integral, available only on DA, DR, DS | |||||
E | Explosion-proof enclosure, control removable, available on DA, DR, DS | |||||
F | Factory Mutual approval, DAW is FM approved as standard | |||||
CIRCUIT SWITCHING OPTIONS |
___2 | SPST opens on pressure increase, elect. code A, mercury switch | ||||
___3 | SPST closes on pressure increase, elect. code A, mercury switch | |||||
_153 | SPDT, elect. code B, mercury switch | |||||
_156 | 2 each SPST, one opens as the other one closes, elect. code A, mercury switch | |||||
_804 | 2 each SPDT, elect. code B, mercury switch, 18" leads, elect. code G, snap switch, screw terminals | |||||
_(___) | Other circuits available, consult factory | |||||
_2 | ___2_ | SPST opens on increase, elect. code I, DS only, mercury switch | ||||
_2 | ___3_ | SPST closes on increase, elect. code I, DS only, mercury switch | ||||
_4(2)(8) | 4122_ | Two stage, includes 2 each SPST, mercury switch | ||||
_4(2)(8) | 4129_ | Two stage, includes 2 each SPST, mercury switch | ||||
_4(2)(8) | 4132_ | Two stage, includes 2 each SPST, mercury switch | ||||
_4(2)(8) | 4123_ | Two stage, includes 2 each SPST, mercury switch | ||||
_5 | ___2 | SPST mercury switch, elect. code H, opens on increase | ||||
_5 | ___3 | SPST mercury switch, elect. code H, closes on increase | ||||
70 | 153 | Snap switch, SPDT, elect. code D, 15A @ 120 VAC | ||||
70(12) | 804 | 2 each SPDT, elect. code F, for ranges above 35 psi only, add 30% to minimum deadbands, 702, 703, 704 only | ||||
72 | 153_ | DS only, snap switch, SPDT, elect. code E | ||||
72 | 804_ | 2 each SPDT, snap switches, elect. code G, DS only | ||||
74 | _____ | Two stage, includes 2 each, SPDT snap switches, elect. code G | ||||
B | Delrin Bushed Movement, for all controls | |||||
RANGES & BOURDON TUBE MATERIALS |
2 | 25S | range 30" Hg vac - 60 psig, type 403SS Bourdon tube | |||
2 | 26S | range 30" Hg vac - 75 psig, type 403SS Bourdon tube | ||||
2 | 5S | range 2-60 psig, type 403SS Bourdon tube | ||||
2 | 6S | range 5-100 psig, type 403SS Bourdon tube | ||||
2 | 8S | range 10-200 psig, type 403SS Bourdon tube | ||||
2 | 9S | range 10-300 psig, type 403SS Bourdon tube | ||||
2 | 9AS | range 40-350 psig, type 403SS Bourdon tube | ||||
2 | 10S | range 25-600 psig, type 403SS Bourdon tube | ||||
2 | 11S | range 50-1000 psig, type 403SS Bourdon tube | ||||
2 | 12S | range 100-1500 psig, type 403SS Bourdon tube | ||||
2 | 13S | range 300-2500 psig, type 403SS Bourdon tube | ||||
2 | 15S | range 500-5000 psig, type 403SS Bourdon tube, not avail. with housing E or back conn. | ||||
2 | 16S | range 800-8000 psig, type 403SS Bourdon tube, not avail. with housing E or back conn. | ||||
3 | 2 | range 30-0" Hg vac, brass Bourdon tube | ||||
3 | 3 | range 10" Hg vac - 12 psig, brass Bourdon tube | ||||
3 | 1 | range 1/8-15 psig, brass Bourdon tube | ||||
3 | 3A | range 1/8-20 psig, brass Bourdon tube | ||||
3 | 4 | range 1-35 psig, brass Bourdon tube | ||||
3 | 27 | range 25" Hg vac - 50 psig, brass Bourdon tube | ||||
3 | 5 | range 2-60 psig, brass Bourdon tube | ||||
3 | 6 | range 5-100 psig, brass Bourdon tube | ||||
3 | 7 | range 5-150 psig, brass Bourdon tube | ||||
3 | 8 | range 10-200 psig, brass Bourdon tube | ||||
3 | 9 | range 10-300 psig, brass Bourdon tube | ||||
4 | 26E | range 30" Hg vac - 75 psig, 316SS Bourdon tube | ||||
4 | 23E | range 5-75 psig, 316SS Bourdon tube | ||||
4 | 6E | range 10-100 psig, 316SS Bourdon tube | ||||
4 | 24E | range 10-150 psig, 316SS Bourdon tube | ||||
4 | 9E | range 10-300 psig, 316SS Bourdon tube | ||||
4 | 21E | range 30-400 psig, 316SS Bourdon tube | ||||
4 | 22E | range 75-800 psig, 316SS Bourdon tube | ||||
4 | 11E | range 100-1000 psig, 316SS Bourdon tube | ||||
4 | 13E | range 200-2500 psig, 316SS Bourdon tube | ||||
8(6) | 23K | range 5-75 psig, 316SS Bourdon tube, carbon steel bottom, F housing standard | ||||
8(6) | 24K | range 10-150 psig, 316SS Bourdon tube, carbon steel bottom, F housing standard | ||||
8(6) | 9K | range 10-300 psig, 316SS Bourdon tube, carbon steel bottom, F housing standard | ||||
CONNECTION & MOUNTING OPTIONS |
1 | Standard housing | ||||
2 | Back connection, not available on D-900 series, not available on ranges 15S, 16S | |||||
3 | Flanged back - standard on "W" models | |||||
4 | Back connection and flanged back, not available for ranges 15S, 16S, or on D-900, 9200, 9500 series | |||||
RANGES | 35(4)(5) | 1N | -60 to 30°F, 150°F max., 304 SS bulb and copper capillary std.; SS special order | T E M P E R A T U R E |
||
35(4)(5) | 3N | range 0 to 100°F, 240°F max., 304 SS bulb and copper capillary std.; SS special order | ||||
35(4)(5) | 4N | range 50 to 150°F, 250°F max., 304 SS bulb and copper capillary std.; SS special order | ||||
35(4)(5) | 5N | range 100 to 200°F, 300°F max., 304 SS bulb and copper capillary std.; SS special order | ||||
35(4)(5) | 7N | range 140 to 300°F, 500°F max., 304 SS bulb and copper capillary std.; SS special order | ||||
35(4)(5) | 8N | range 250 to 415°F, 550°F max., 304 SS bulb and capillary std. | ||||
35(4)(5) | 9N | range 350 to 550°F, 600°F max., 304 SS bulb and capillary std. | ||||
35(4)(5) | 10N | range 100 to 300°F, 500°F max., 304 SS bulb and copper capillary std.; SS special order | ||||
35(4)(5) | 11N | range 100 to 500°F, 600°F max., 304 SS bulb and capillary std. | ||||
36(4)(5)(10) | 5NS | range 100 to 200°F, 300°F max., 304 SS bulb std. | ||||
36(4)(5)(10) | 6NS | range 140 to 250°F, 380°F max., 304 SS bulb std. | ||||
CONNECTION & MOUNTING OPTIONS |
37(4)(5)(11) | Same as 36 except back connection, 304 SS bulb std. | ||||
38(4)(5) | Same as 36 except has flanged back | |||||
39(4)(5)(9) | Same as 35 except has flanged back and back connection |
(1) Not available on D_ _-_5, 74 or 95.
(2) Available on DA only.
(3) Not available on D_ _ _-70_ _.
(4) & (5) Not available with 9, 92, 95 Diaph. Seals.
(6) Available also as _ _ 28, 58, 708 and 728. Not available with E or H housing or 70-804 circuit.
(7) F available only as DAF, DSF, DRF, DAHF, DRHF, DSHF, not all ranges or circuits.
(8) Switch rating for D-400: AC, 120V @ .3A, 240V @ .15A, 24V @ .8A, DC, 120V @ .15A, 240A @ .07A. Not available for 440V service.
(9) Available only as _ _39, 539, 239, 7039, 7239, 439 and 7439.
(10) Available only as _ _36, 7036 and 7236.
(11) Available only as _ _37, 7037 and 7237.
(12) Available only on 702, 703 and 704.
ELECTRICAL RATING CODES
For Mercury Switch Contacts | ||||||||
CODE | CIRCUIT SUFFIX NO. |
AC CAPACITY | DC RESISTIVE | HORSEPOWER | ||||
120V | 240V | 440V | 120V | 240V | AC | DC | ||
A | -2, -3 | 10A | 5A | 3A | 10A | 5A | 3/4 | 1/3 |
B | -153, -804 | 4A | 2A | (1) | 4A | 2A | 1/8 | NA |
C | -2, -3 | (6) | (6) | (6) | 10A | 5A | 3/4 | 1/3 |
H | -2, -3 | 5A | 2A | NA | 2-1/2A | 1A | 1/8 | 1/10 |
I(2) | -2, -3 | 0.3A | 0.15A | NA | 0.15A | 0.07A | NA | NA |
For Snap-Action Contacts | ||||||||
CODE | CIRCUIT SUFFIX NO. |
AC CAPACITY | DC RESISTIVE | HORSEPOWER | ||||
120V | 240V | 440V | 120V | 240V | AC | DC | ||
D | -153 | 15A | 15A | 15A@480V | 1/2A | 1/4A | 1/8 | NA |
E | -153 | 15A | 15A | NA | (4) | (4) | (3) | NA |
F | -804 | 12A | 10A | 5A | 1/2A | 1/4A | (3) | NA |
G | -804 | 5A | 5A | NA | (5) | (5) | NA | NA |
NOTES:
(1) -153 circuit available 1A 440V AC on special order.
(2) Also rated 0.9A at 24V AC.
(3) 1/4 HP at 120V AC, 1/2 HP at 240V AC.
(4) DC rated controls (up to 10A.
(5) 5A, 30V DC resistive.
(6) 17A non-inductive at 120/240/440V AC.
Product Literature
Manuals
Catalog Pages
SDS
Approvals
- CSA - Comfort Conditioning Equipment
- CSA - Ind'l Control Equip/Misc Apparatus
- CSA - Temp Indicating & Reg Equipment
- FM-Fire Pump (DA)
- FM-Supervisory Sw Fuel Oil (DAF, DSF, DRF, DRW)
- FM-Supervisory Switch
- UL-Controllers, Refrigeration-US (DA/DR)
- UL-Controls, Limit-US
- UL-Motor Controllers-Canada
- UL-Motor Controllers-Hazardous Locations-US
- UL-Motor Controllers-US
- UL-Switches-US
Drawings
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.
- 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.
Photo Downloads
You must be logged in to view this content.Click here to login to your account.