Dwyer 1800 User Manual [en, es]

3-39/64

[91.68]

Ø7/8 [22.23]

CONDUIT

CONNECTION

3-1/8

[79.38]

Ø4

[101.60]

1-27/32

[46.83]

1-1/8

[28.57]

1/8 FEMALE NPT
HIGH PRESSURE

CONNECTION

1/2 MALE NPT

MOUNTING SPUD

1/8 FEMALE NPT
LOW PRESSURE

CONNECTION

3-27/32

[97.63]

2-3/32

[53.18]

2-1/8

[53.98]

CLEARANCE FOR

COVER REMOVAL

3/4

[19.05]

Series

1800

Low Differential Pressure Switches
for General Industrial Service

Specifications — Installation and Operating Instructions

Bulletin E-53

Model 1823 pressure switch. UL
and CSA Listed, FM and
CENELEC approved.

One of our most popular pressure switches. Combines small

size and low price with 2% repeatability for enough accuracy for
all but the most demanding applications. Set point adjustment
inside the mounting switch on one side of a wall or panel with
adjustment easily accessible on the opposite side.

Series 1823 pressure switch.
Conduit enclosure removed to
show electric switch.

Construction and dimensions. Series 1823 pressure switches.

SPECIFICATIONS
Service: Air and non-combustible, compatible gases.
Wetted Materials: Consult Factory.
Temperature Limits: -30 to 180°F (-34 to 82.2°C). 1823-00,

-20 to 180°F (-28.9 to 82.2°C).

*Model 1823 shown; (1823 replaces 1820, 1821 and 1822
which are similar).

Environmental (MIL) Switch

Unlisted Model 1820 can be furnished with special snap switch
sealed against the environment for high humidity and/or for
government applications. Similar to standard Model 1823
except dead band is slightly greater. Specify Model 1820
(Range No.) "MIL" in ordering.

Pressure Limits: 10 psig (68.95 kPa) continuous, 25 psig
(172.4 kPa) surge.

Switch Type: Single-pole double-throw (SPDT).
Repeatability: ±2%.
Electrical Rating: 15 A @ 120-480 VAC, 60 Hz. Resistive 1/8

HP @125 VAC, 1/4 HP @ 250 VAC, 60 Hz. De-rate to 10 A for
operation at high cycle rates.
Electrical Connections: 3 screw type, common, normally
open and normally closed.

Process Connections: 1/8˝ female NPT.

SERIES 1823 SWITCHES —
OPERATING RANGES & DEADBANDS

At Min.

0.05

0.06

0.08

0.10

0.14

0.18

0.35

0.56

1.30

Approximate

Dead Band

Operating

Model

Number

1823-00
1823-0
1823-1
1823-2
1823-5
1823-10
1823-20
1823-40
1823-80

DWYER INSTRUMENTS, INC.

Range,

Inches W.C.

0.07 to 0.22

0.15 to 0.5

0.3 to 1.0

0.5 to 2.0

1.5 to 5.0

2.0 to10
3 to 22
5 to 44
9 to 85

Set Point

At Max.

Set Point

0.05

0.06

0.08

0.12

0.28

0.45

0.70

1.10

3.0

Mounting Orientation: Diaphragm in vertical position. Consult
factory for other position orientations.

Set Point Adjustment: Screw type inside mounting spud.
Weight: 1 lb, 5 oz (595 g).
Agency Approvals: CE, UL, CSA, FM.

Phone: [phone] www.dwyer-inst.com

P.O. BOX 373 • MICHIGAN CITY, INDIANA 46361, U.S.A. Fax: [phone] e-mail: [e-mail]

INSTALLATION

COM.
N.C.

N.O.

1. Select a location free form excessive vibration and where oil
or water will not drip upon the switch. See special housings for
unusual conditions.

2. While not required, positioning the pressure connections
down is recommended. Mount the switch with the diaphragm
in a vertical plane. Switch with the diaphragm in a vertical
plane. Switch must be recalibrated for each change in
operating position.

3. Connect switch to source of pressure differential. Metal tubing
with 1/4" O.D. is recommended but any tubing system which
will not restrict the air flow is satisfactory. Note that the low
pressure connection may be made to the 1/2" spud at the
back of the switch if desired. If so connected, drill 1/16"
diameter holes in the Spring Retainer flange and the head of
Adjustment Screw to provide opening to the switch interior
and plug the other low pressure connection.

4. Electrical connections to the standard single pole, double
throw snap switch are provided by means of screw terminals
marked "common", "norm open", and "norm closed". The
normally open contacts close and the normally closed contact
open when pressure increases beyond the set point.

5. Switch loads should not exceed the maximum specified
current rating of 15 amps resistive. Switch capabilities
decrease with high load inductance or rapid cycle rates.
whenever and application involves one or more of these
factors, the user may find it desirable to limit the switched
current to 10 amps or less in the interest of prolonged switch
life.

ADJUSTMENT

1. If the switch has been factory preset, check the set-point
before placing in service to assure it has not shifted in transit.

2. If switching has not been preset or it is desired to change the
point, observe the following procedure:
a. To adjust the set point turn the slotted Adjustment Screw

clockwise to increase the set point and counterclockwise to
decrease the set point.

b. The following is a recommended procedure for calibrating

or checking calibration: Use a "T" assembly with three
rubber tubing leads, all as short as possible and the entire
assembly offering minimum flow restriction. Run one lead
to the pressure switch, another to a manometer of known
accuracy and appropriate range, and apply pressure
through the third tube. Make final approach to the set point
slowly. Note the manometer and pressure switch will have
different response characteristics due to different internal
volumes, lengths of tubing, oil drainage, etc. Be certain
switch is checked in position it will assume in use, i.e.
vertical, horizontal, etc.

4-1/6

[103.19]

1-1/2 [38.10]

1-1/4 [31.75]

3/32 [2.38]

1-1/2 [38.10] TYP

1/8 FEMALE NPT HIGH

PRESSURE CONNECTION

1-7/16

[36.53]

6 [15.40]

SQ

1/2 FEMALE NPT

CONDUIT

CONNECTION

4 [101.60]

TYP

[76.20]

6-3/4

[171.45] TYP

7-1/2

[190.50]

3

1/8 FEMALE NPT
LOW PRESSURE

CONNECTION

Ø5/16 [7.94]

MOUNTING

HOLES

TYP 4 PLACES

3/4 [19.05]
CLEARANCE FOR
COVER REMOVAL

Weatherproof Enclosure

16 ga. steel enclosure for unusually wet or oily conditions.
Withstands 200 hour salt spray test. Gasketed cover. Weight 5­1/2 lb (2.5 kg). Switch must be installed at factory. Specify
"WP" in addition to switch catalog number.

6-1/2 [165.10]

CLEARANCE FOR

4X Ø.281

[7.14]

1/8 FEMALE NPT

HIGH PRESSURE

CONNECTION

2X 4-1/4
[107.95]

2X 6-1/8
[155.58]

1/8 FEMALE NPT
LOW PRESSURE CONNECTION

COVER REMOVAL

6-5/8 [168.28]

3 [76.20]

1/2 NPT PROCESS
CONNECTION

3X 1-1/16 [26.99]

Explosion-Proof Housing

Cast iron base and aluminum dome cover. Approximate weight
7-1/2 lb (3.4 kg). Specify "EXPL" in addition to switch catalog
number. Rated Class I, Groups C & D, Div. 1. Class II, Groups
E, F, & G, Div. 1.

DWYER INSTRUMENTS, INC.

Phone: [phone] www.dwyer-inst.com

P.O. BOX 373 • MICHIGAN CITY, INDIANA 46361, U.S.A. Fax: [phone] e-mail: [e-mail]