Dwyer 1831 - Manual

DWYER INSTRUMENTS, INC.
Phone: 219/879-8000 www.dwyer-inst.com
P.O. BOX 373 • MICHIGAN CITY, INDIANA 46360, U.S.A. Fax: 219/872-9057 e-mail: [email protected]
One of our most popular differential pressure switches is now available
with a DPDT switch. The 1831 combines small size with 4% set point
repeatability. Absolutely no power is required to operate the DPDT
switch. Set point adjustment on the switch is easily accessible for
modifying the set point. A mounting bracket is included for simplified
installation.
MANUAL RESET OPERATION - ACTIVATE ON INCREASE
Models with “manual reset” are DPDT configuration and operate as
follows: If differential pressure increases above the set-point, the snap
switch is actuated or latched so N.O. contacts are closed and N.C.
contacts are open. They will remain in that condition even if differential
pressure decreases below the set-point until manually deactuated by
reset lever.
SET POINT THRESHOLD CHECk:
The reset lever can act as a test feature during system installation or
maintenance, even if set point threshold is not exceeded. A periodic
lever override is recommended to ensure proper switch performance.
Pushing the lever to the right (when viewed from the cover side of the
switch with the ports pointed down) will cause the switch to change state,
simulating a condition in which the set point threshold has been
exceeded. The lever then must be manually reset, pushing the lever to
the left to deactuate the switches to complete the override procedure.
CAUTION: If the switch set point threshold has been
exceeded and the lever is in the tripped position on the right,
the lever can be moved to the left position and manually held
by the user, overriding the alarm condition as long as the
user holds it there. If the switch set point threshold is still
exceeded and the operator releases the reset lever, it will
pull back to the tripped position on the right and remain in
that location until the set point has dropped below the set
point threshold and the user resets the lever normally.
SPECIFICATIONS
Service: Air and non-combustible, compatible gases.
Environment: Intended for indoor use.
Wetted Materials: Consult factory.
Temperature Limits: -30 to 180°F (-34.4 to 82.2°C).
Pressure Limits: 10 psig (68.95 kPa) continuous; 25 psig (172.4 kPa)
surge.
Humidity Limits: 80% RH (non-condensing).
Altitude Limits: 6560 ft (2000 m) max.
Switch Type: 2 SPDT.
Actuation Time Difference: 1 millisecond maximum actuation delay
between contacts.
Repeatability: ±4% max of setpoint.
Electrical Rating: 4A resistive @ 125/250 VAC (~); 50/60 Hz. 3A
inductive 30 VDC ( ); 5A resistive 30 VDC ( ).
Electrical Connections: Screw type terminal block.
Installation Category: II (transient over-voltage).
Process Connections: 1/8˝ female NPT.
Mounting Orientation: Diaphragm in vertical position. Consult factory
for other position orientations. Mounting bracket included.
Set Point Adjustment: Screw type inside mounting spud.
Weight: 1 lb 2 oz (522 g).
Series 1831 Low Differential Pressure Switches
Specifications - Installation and Operating Instructions
Bulletin P-1831
Series 1831 pressure switch.
4-3/8
[111.13]
2X 3-1/16
[77.79]
1-5/8
[41.28]
4-1/16
[103.19]
2X Ø7/8
CONDUIT OPENING
2-5/32
[54.76]
CLEARANCE FOR
COVER REMOVAL
3-11/16
[93.65]
RESET
LEVER
3-5/8 [92.08]
1-3/32 [27.76]
1-7/64 [28.17]
1/2 MALE NPT
MOUNTING STUD
1/8 FEMALE NPT
LOW PRESSURE
CONNECTION 1/8 FEMALE NPT
HIGH PRESSURE
OPENING
ø.875 [22.23]
2X ø9/64 [3.57]
2
2-3/4
[69.86]
3-1/4
[82.55]
3/4
[19.05]
3-3/16 [80.98]
3X 2
[50.80]
2-5/16
[58.74]
A-389 MOUNTING BRACKET
Description
Direct current
Alternating current
Protective conductor terminal
On (supply)
Off (supply) Symbol
Explanation of Symbols:
~
Publication
IEC 50417 - 5031
IEC 50417 - 5032
IEC 50417 - 5019
IEC 50417 - 5007
IEC 50417 - 5008