Install Instructions

Series 1630 Differential Pressure Switch
Specications - Installation and Operating Instructions
Bulletin E-52
Model 1638 pressure switch -
U.L. and C.S.A. listed F.M. approved
Our highest precision conventional large diaphragm pressure switch provides
maximum dependability. In addition it incorporates a visible set point indicator for
maximum convenience. U.L. and C.S.A. listed, F.M. approved for general service,
these switches are suitable for most applications in air conditioning and industrial
service. Electrical capability of 15 amps handles most small electrical loads.
Environmental (MIL) Construction. Unlisted Model 1635 can be furnished with special
snap switch and silicone rubber diaphragm for high humidity and/or for government
applications. Similar to standard Model 1638 except dead band is slightly greater.
Specify Model No. 1635 (range No.) MIL in ordering. Example: 1635-5-MIL.
HOUSINGS FOR USE WITH MODEL 1638 SWITCH
(also suitable for Models 1626, 1627 and 1640 switches)
MODEL 1638:
Operating Ranges, Dead Bands and Ratings.
U.L. and C.S.A. Listed, F.M. Approved.
SPECIFICATIONS
Temperature Limits: -30°F (-34.4°C) for dry air or gas to 110°F (43.3°C). (Consult
factory for higher temperature applications.)
Maximum Surge Pressure: 25 psig.
Rated Pressure: 10 psig.
Pressure Connections: 1/8″ NPT(F).
Electrical Rating: 15 amps, 120-480 volts, 60 Hz. A.C. Resistive 1/8 H.P. @ 125
volts, 1/4 H.P. @ 250 volts, 60 Hz. A.C.
Wiring Connections: 3 screw type, common, normally open and normally closed.
Set Point Adjustment: Screw type with enclosed scale.
Housing: 16 ga. steel, zinc plated, dichromate dipped for 200 hour salt spray test.
Diaphragm: Silicone rubber.
Calibration Spring: Stainless steel.
Weight: 3 lbs, 3 oz (1.50 kg).
Installation: Diaphragm vertical.
4
[101.60]
3
[76.20]
TYP
1/2
[12.70]
TYP
2
[50.80]
TYP
21/32 [16.66]
Ø9/32 [7.14]
MOUNTING HOLE
TYP
4 PLACES
6-1/2 [165.10]
Ø7-7/8
3-1/8
[79.37]
22.5Ø
1/8 FEMALE
NPT LOW
PRESSURE
CONNECTION
1/8 FEMALE NPT
HIGH PRESSURE
CONNECTION
3 [76.20]
1/2 CONDUIT
CONNECTION
MODEL CHART
Model
Number
Operating Range
Inches, W.C.
Approximate Dead Band
At Min.
Set Point
At Max.
Set Point
1638-0
1638-1
1638-2
1638-5
1638-10
0.05 to 0.25
0.20 to 1.0
1.0 to 3.0
2.0 to 6.0
3.0 to 12
0.04
0.04
0.06
0.07
0.11
0.05
0.06
0.08
0.25
0.30
®
DWYER INSTRUMENTS, INC.
P.O. BOX 373 • MICHIGAN CITY, INDIANA 46360, U.S.A.
Phone: [phone]
Fax: [phone]
www.dwyer-inst.com
e-mail: [e-mail]