Dwyer instruments, inc – Dwyer DFS User Manual

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Figure A: Install Capillary in Horizontal Pattern Only

Set Point Adjustment
The set point shown on the scale of the Series DFS is the temperature at which the
switch contacts 11-14 and 21-24 will OPEN on a fall in sensed temperature.

To adjust the set point, use a screwdriver or wrench to turn the range adjustment screw
located at the top of the spring housing above the scale. Clockwise rotations decrease
the set point. Counter-clockwise rotations increase the set point.

Figure B: Switch Action On Decrease In Temperature

Figure C: Internal View of Series DFS

Wiring
The conduit opening located on the bottom of the Series DFS is designed for installing
a 1/2˝ NPT connector. For best results, wiring should be completed with 14 AWG solid
copper wire.

1. Use a screwdriver to loosen terminal screws.
2. Strip the insulated wire ends 3/8˝ and insert under cup washers on the switch block.
3. Securely tighten the terminal screws.
4. Manually test the operation of the DPDT switch by depressing the test lever located

below and to the left of the controller spring.

Resetting Manual Reset Models
On a temperature fall below set point, switch contacts 11-14 and 21-24 open and
contacts 11-12 and 21-22 close. The switch will remain locked in the switched position
until the controller is manually reset by depressing the reset button located on the top
of the controller case.

MAINTENANCE/REPAIR
Upon final installation of the Series DFS, no routine maintenance is required. The
Series DFS is not field serviceable and should be returned if repair is needed (field
repair should not be attempted and may void warranty).

WARRANTY/RETURN
Refer to “Terms and Conditions of Sales” in our catalog and on our website. Contact
customer service to receive a Return Goods Authorization number before shipping the
product back for repair. Be sure to include a brief description of the problem plus any
additional application notes.

Printed in U.S.A. 11/11

FR# R6-443898-00

The controller can not be reset until after the sensed temperature
rises 5°F (3°C) above the set point.

NOTICE

DWYER INSTRUMENTS, INC.

Phone: 219/879-8000

www.dwyer-inst.com

P.O. BOX 373 • MICHIGAN CITY, INDIANA 46361, U.S.A.

Fax: 219/872-9057

e-mail: [email protected]