Honeywell T775A User Manual

1 63-2489
T775A,B,C,D
Remote Temperature Controller
The T775 family of Electronic Remote Tem-
perature Controllers provide on-off temperature
control for ducts, tanks, chillers, heating and re-
frigeration units, and other applications where
electronic accuracy in addition to remote sensing
is desired.
In addition, certain models of the T775 family
of controllers provide on-off temperature control
of heating, cooling, and ventilating systems in agri-
cultural confinement buildings, storage areas and
heavy industrial applications.
T775A,B
T775C,D
■ T775A models provide staged on-off control with
one temperature input and one to four relay output
stages.
■ T775B models provide staged on-off control with
two temperature inputs and two to four relay output
stages.
■ T775C models provide staged on-off control with
one temperature input and four relay output stages.
■ T775D models provide staged on-off control with
two temperature inputs and four relay output stages.
■ T775C,D models meet National Electrical Code
(Article 547) requirements for animal confinement
buildings.
■ Setpoint temperature range is -40° to +220° F (-40°
to +104°C).
■ Ambient temperature range is -30° to +140°F for
one and two stage models and -30° to +125°F for
three and four stage models.
■ Linear platinum temperature sensor with T775A,B.
■ Water-tight linear platinum temperature sensor with
T775C,D.
■ Adjustable temperature range and differential.
■ LCD indication for mode and output status.
■ Keypad provides ease of programming and operation.
■ Accuracy is within +/- 1°F (at nominal operating
ambient temperature of 77°F and voltage input).
■ Stage(s) independently programmed for heating or
cooling.
■ 24/120/240 Vac input voltage.
■ Spdt relay outputs.
IMPORTANT: The T775 is an operating control, not a
limit or safety control. If used in applications requir-
ing safety or limit controls, a separate safety or limit
control device should be used in conjunction with the
T775.
G.R. • 12-94 • ©Honeywell Inc. 1994
63-2489
CONTENTS
Specifications ................................................. 2
Ordering Information ..................................... 2
Installation ..................................................... 5
Description/Operation ................................... 8
Checkout....................................................... 11

Honeywell T775A Specifications

General

Brand	Honeywell
Model	T775A
Category	Temperature Controller
Language	English

Summary

Specifications Overview

T775A,B and T775C,D Model Details

Details on T775A,B and T775C,D models, their applications, and electrical ratings.

Contact Ratings and Sensor Specifications

Electrical contact ratings, sensor type, accuracy, display resolution, and environmental limits.

Operational and Approval Details

Information on setpoint range, operating temperatures, humidity, and product approvals.

Physical and Mounting Specifications

Details on controller dimensions and mounting instructions.

Product Installation Guide

Pre-Installation Steps and Warnings

Essential instructions and safety warnings before beginning the installation process.

Controller Location and Mounting

Guidance on selecting an appropriate location and mounting the controller unit.

Temperature Sensor Installation

Instructions for locating and mounting the remote temperature sensor.

Controller Description and Operation

Programming Stage Control Values

Procedure for setting stage setpoints and differentials for the controller.

Control Algorithm and Modes

Explanation of heating and cooling modes, including setpoint and differential behavior.

Keypad, Display, and Configuration Settings

Using the keypad, display, °F/°C selection, and DIP switches for operation.

Error Messages and Calibration

Troubleshooting common error codes and details on setpoint calibration.

Post-Installation Checkout

Checkout Procedure and Verification

Steps to verify controller installation, settings, and output operation.

Interpreting Checkout Results

Using the checkout table and example to confirm load status and operating parameters.