Dwyer DA, DS Snap Action Switch Manual

Series DA/DS-7000 Bourdon Tube Pressure Switches

2-1/4

[22.23]

Specications - Installation and Operating Instructions

[57.15]

Bulletin IN-523

Series DA/DS-7000 Bourdon Tube Pressure Switches are SPDT snap-action
switches that combine extremely high sensitivity and repeatability with easily
adjustable set and reset points through non-interactive external adjustments. These
switches have visible calibrated dials for set points and on-off indicators to indicate
switch actuation. DA models are equipped with two external adjustments. One sets
the high pressure operating point; the other sets the reset point. Deadband or the
difference between set and reset points is adjustable over the full scale. DS models

have a xed deadband.

Note: The DS7300 has no status indicator.

INSTALLATION

The switch may be mounted in any position. Select a location recommended by
equipment manufacturer. Where excessive vibration occurs, mount the switch
remotely, using an appropriate remote connection and mounting bracket. See
accessories, below.

ACCESSORIES

Ø6-1/64

[152.8]

1/4 NPT

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.
Switch Type: See circuit chart.
Electrical Rating: See electrical ratings chart.
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 ranges 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 (2.7kg); Explosion-proof:

8 lb (3.5 kg).

Deadband: See Ranges and Differentials Chart.

7/8

1-5/8

[41.28]

ADJUSTMENT

SCREWS

1/2˝ CONDUIT HOLE

5/8

[15.88]

Mounting bracket

33-25

Pigtail siphon

42-52: 250 psig max

42-58: 2000 psig max

Remote connection

49-62: 6 ft copper - 300 psig max

49-62HP: 6 ft copper - 2500 psig max

49-210: 12 ft 316 SS - 3000 psig

DWYER INSTRUMENTS, INC.

P.O. BOX 373 • MICHIGAN CITY, INDIANA 46360, U.S.A.

CAUTION

passing through the switch is within specied rating.

When testing a boiler or system, never exceed maximum pressure rating on control or
it may be seriously damaged. Remove control if higher pressures are required.

Do not fail to use a siphon on steam where range is 35 lb (2413 mbar) or more.

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Fax: [phone]

Control movement must not be oiled. Do not overload. Note

electrical rating on name plate and be sure that total current

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GENERAL PURPOSE CONTROLS, TYPES DA, DL, DR, DS

T

HOLE

[38.10]

[3] Ø13/64 [5.159]

Ø6-1/2
[165.1]

[3] REAR FLANGE

HUB

2-7/8

1/4 NPT

7-3/4 [196.9]

3-1/2 [88.90]

[250.83]

5 [127]

Mount control in any position. Do not twist the case when installing. Use a wrench on

the square part of the control connection. On controls with operating Range No. 15S
(500 to 5000 psi (34.47 to 344.75 bar)) or Range No. 16S (800 to 8000 psi (55.16
to 551.6 bar)), be sure the special sealing nut (with PTFE insert) is turned to the
uppermost threaded section of the 1/2˝ pressure connection. Apply a at open-end
wrench to the at side of the bottom pressure connection when piping the control.

After properly connecting the control, tighten the sealing nut to assure a leak-proof
connection.

HOLES FOR
FLANGE
SCREWS

1/4 NPT

WATERTIGHT AND WEATHERPROOF
NEMA 2, 3, 4, 5, TYPES DAW, DRW, DSW

These switches are supplied with anged case, bottom connection, for surface

mounting only.

MOUNTING HOLES

Ø7 [177.80]

[71.63]

1-1/2

1/4 NPT

General purpose types DA, DS, DR, DL

FLANGED CASE CONTROLS

Mount by means of the three holes in the ange. Note: Series D7030 when used
for steam with operating ranges of 35 psi (2.413 bar) or higher, must be siphoned to

prevent live steam entering the Bourdon tube. With high-pressure steam exceeding

100 psi (6.895 bar), use a remote connection. (Note: accessories on Page 1.)
Series D-7020 incorporate an orice as standard in the pressure connection to

dampen surges or pulsations.

Flange for surface mounting

1-1/8

[28.58]

Ø6-1/64 [152.8]

1/2˝ CONDUI

ADJUSTMENTS

GASKETED COVER

Weather-proof types DAW, DSW, DRW

EXPLOSION-PROOF TYPES DAH, DRH, DSH

Mount with mounting lugs attached to control housing.

BREATHER
[OPTIONAL]

9-7/8

Explosion-proof types DAH, DRH, DSH

WIRING

Wire in accordance with the National Electrical Code and local regulations. For general

purpose controls, use a short piece of BX between the rigid conduit and the control
so the control will not be subjected to conduit expansion and contraction. Where the
control is directly connected into the load circuit, it should be connected into the hot
side of the line. Do not exceed electrical rating as stamped on the control nameplate.
DS-7300 controls are equipped with a terminal block. Field connection should be
made to terminal block pole in common with required pole of the control’s switch. The
color code is:

MOUNTING HOLES [OPTIONAL]

[2] STD. Ø13/32
[10.32] MOUNTING
HOLES

1/2 NPT

1/2˝
CONDUIT

3/4˝ CONDUIT
CONNECTION

Black - Common

Blue - ON Hi
Red - ON Lo

ADJUSTMENTS: HOW TO SET OPERATING POINT

SWITCH CARRIE
ST
WITH

PIVO
BEARINGS,
AND BOTT
BUSHED WITH

ACETAL PIN

R

Double Adjustment Types - Fully Automatic:

With double-adjustment switches (prexed DA, DAH or DAW), adjust the upper pointer
˝U˝ to set HIGH PRESSURE POINT for switch operation and adjust the lower pointer
˝L˝ to set LOW PRESSURE OPERATING POINT. The difference between the ˝U˝ and
˝L˝ pointers is the operating differential between ˝on-off˝ switch operation.

Switch indicator

orange indicates

on high

U - Upper pointer

L - Lower pointer

Double-adjustment types fully automatic

Semi-Automatic Control with Manual Reset:

Models prexed DR, DRH, DRW and with sufx L or U (example: DR-7021-153U)

have a single adjustment that sets the operating point for automatic operation. A push­button reset must be operated manually to restore the circuit to the original position

after automatic operation. Example: Type DR-7021-153L has a circuit that opens

automatically on a pressure rise to the pressure indicated by the pointer on the scale;
no matter how much the pressure drops, the circuit will not re-close until the reset

button is operated. Sufx L denotes control will operate automatically on an increase.
Sufx U denotes control will operate automatically on an decrease.

SINGLE ADJUSTMENT TYPES — FULLY AUTOMATIC:

Models prexed DS, DSH, DSW, N3DSW are equipped with a single adjustment.
Differential is xed (not adjustable). The single pointer on the scale sets the pressure

at which switch operation occurs. Differential is listed in chart indicates approximate

xed differential.

Switch operating
indicator

Single adjustment

Single adjustment types fully automatic

LOCKING DEVICE

When the control has been adjusted to desired range, the locking bar may be inserted
between the adjustment screws with the slot passing over the projecting lugs. By
placing a sealing wire between the locking bar and the hole in the lug protruding from
the adjustment assembly, adjustments cannot be tampered with.

For DRF, DAW, DRW, adjusting knob cover may be sealed in place with sealing wire

through cover bolt hole. For DAH, sealing wire may pass through locking bar and hole

in hub above adjusting knobs.

ACETAL BUSHED MOVEMENT ˝B˝

Acetal bushed movements prolong control life by alleviating wear of metal surfaces due
to excessive vibration and/or pulsation. They also prolong switch life in environments

where corrosion may be a factor. Models with Acetal movements are identied by the
letter ˝B after the sufx number. Examples: -153B, -153UB, etc.

Semi-automatic types with manual reset

Adjustment

Reset

CONTROL NUMBER

Part of the control number (the fourth number in the sequence) identies the type of

control case. Digit 1 of 7021, 7031, 7041, denotes a plain case with bottom connection.
Digit 2 of 7022, 7032, etc., denotes a plain case with back connection. Digit 3 of 7023,

7033, 7043, etc., denotes a anged case with bottom connection. Digit 4 of 7024,
7034, etc., denotes a anged case with back connection.

ACETAL PIN

BAR LINK
ACETAL BRUSHED

T POINT

TOP

OM,

ACETAL

R

OP POST SLEEVED

ACETAL

PIVOTAL END BEARING
AND CONNECTION BA
PIN OF ACETAL

Acetal bushed movement ˝B˝

CIRCUITS (SWITCH OPERATION)

Sufx number after control number denotes switch action:
Sufx -153 designates SPDT; one circuit closes as other circuit opens.
Sufx - 804 designates two SPDT switches; two close, two open.

TYPE DA Double

Ranges

Bourdon Tube Material Range Number
Brass

Bourdon Tube

403 SS

Bourdon Tube

316 SS

Bourdon Tube

316 SS

Bourdon Tube

Carbon Steel

Bottom Connection

Code 120 V 240 V 480 V 120 V 240 V 120 V 240 V
D

E

F
G

Circuit Sufx No. Switch Action on Pressure Increase

-153

-804

*Minimum differentials increase when using multiple circuits. Controls using #804 circuits in ranges over 35 psig have 30%
higher minimum differentials; ranges under 35 psig are not available in Code F.

2
3
1
3A
4
27

5

6
7
8
9

Range
Number

25S

26S

5S

6S
8S
9S
9AS
10S
11S
12S
13S

15S

16S

Range
Number

26E
23E
6E
24E
9E
21E
22E
11E
13E

Range
Number

23K
24K
9K

Electrical Ratings
Electrical Ratings
AC Capacity DC Capacity AC Horsepower

10A

15A

12A

5A @ 250 AC. Resistive and Inductive; 30V DC Resistive

SPDT: one OPENS as one CLOSES (2)
SPDT: two OPEN as two CLOSE

Adjustable Operating
Range (psig)

0 to 30 in Hg VAC

1.0 in Hg VAC-12
1/8 to 15

1/8 to 20

1 to 35
25 in Hg VAC-50

2 to 60

5 to 100
5 to 150

10 to 200
10 to 300

Adjustable Operating
Range (psig)

30 in Hg VAC-60
30 in Hg VAC-75

2 to 60

5 to 100

10 to 200
10 to 300

40 to 350
25 to 600
50 to 1000
100 to 1500
300 to 2500
500 to 5000

800 to 8000

Adjustable Operating
Range (psig)

30 in Hg VAC-75
5 to 75

10 to 100

10 to 150

10 to 300
30 to 400

75 to 800

100 to 100

200 to 2500

Adjustable Operating
Range (psig)

5 to 75
10 to 150

10 to 300

10A

NA

15A

15A

10A

5A

.5A
NA
.5A

Adjustment Minimum

Differential (psig)

SPDT

DA-7031-153
DAW-7033-153
DAH-7031-153

13.5 in Hg

6
6
6
7
12
9

13.5

24
24

37.5

SPDT

DA-7021-153
DAW-7023-153
DAH-7021-153

18

22.5

13.5

19.5

22.5

28.5

30

67.5

142.5
195

390

1350
2250

SPDT

DA-7041-153
DAW-7043-153
DAH-7041-153

15

12

15

16.5

42
78
180

285

600

SPDT

DA-7041-153
DAW-7043-153
DAH-7041-153

12

16.5

42
See Code F*

See Code D See Code E See Code D

.25A
NA.25A

Electrical Rating
D-7000 D-7200

D
F*

1/8
1/4
1/4

E

G

TYPE DS Single Adjustment
Fixed Differential (psig)

SPDT

DS-7231-153
DSW-7233-153
DSH-7231-153

3 in Hg

1.5

1.5

1.5

1.5

2.5

2

2.5

3.5

4.75

6

SPDT

DS-7221-153
DSW-7223-153
DSH-7221-153

3.5

3.5

3

3.5

4.75

7
7
12
22

35

60
200

500

SPDT

DS-7241-153
DSW-7243-153
DSH-7241-153

3.5

4

3.5

4.5

8
12

25
35
75

SPDT

DS-7241-153
DSW-7243-153
DSH-7241-153

4
4
8

1/4
1/2
1/2

(2) SPDT
DS-7231-804
DSW-7233-804
DSH-7231-804

2.5 in Hg

1.25 in

1.25

1.25

1.5

2

1.5

2

3.5

4
6

(2) SPDT
DS-7221-804
DSW-7223-804
DSH-7221-804

3
3

2.5

3
4
6
6
10
20
30

50

110
180

(2) SPDT
DS-7241-804
DSW-7243-804
DSH-7241-804

4

2.5

4
3
6
10
17
30

95

(2) SPDT
DS-7241-804
DSW-7243-804
DSH-7241-804

2.5

3
6

DWYER INSTRUMENTS, INC.

P.O. BOX 373 • MICHIGAN CITY, INDIANA 46360, U.S.A.

Printed in U.S.A. 3/22 FR# 441853-00 Rev. 4©Copyright 2022 Dwyer Instruments, Inc.

Phone: [phone]

Fax: [phone]

www.dwyer-inst.com

e-mail: [e-mail]