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STP SERIES Install, Operation, and Maintenance Manual
SECTION 3: OPERATION AND CONTROLS
Rev-1
Diversified Heat Transfer, Inc.
•
439 Main Road, Route 202
•
Towaco, New Jersey 07082
Page
53
of
97
STP Manual
PHONE: 800-221-1522
•
WEBSITE: www.dhtnet.com
09/11/2019
3.14 DRY CONTACTS
The following two types of contacts are available for remote monitoring of unit:
3.14.1 Contact closure input (enable/disable)
Dry Contacts C and LA are available on the PID temperature controller to remotely start/stop the
unit if required.
This input is supplied with the current transformer. Contact closure on the remote switch disable
(stop) the unit.
3.14.2 Fault Relay Contacts
Fault relay R1 terminals 11 and 14 shown below (also shown in Section 6.4) available on the
terminal block inside the control panel box for remote alarm indication purposes. This relay is a
Double Pole Double Throw (DPDT) type which energizes when fault condition occurs. Fault can
be cleared by pressing the Alarm Silence button.
It has one set of normally open contacts (between contacts 11 and 14 and 21 and 24) and
normally closed contacts (between contacts 11 and 12 and 21 and 22). Normally open (NO)
contacts are rated for 8 amps and maximum switching voltage is 400 VAC.