Honeywell T775L Series User Manual

INSTALLATION INSTRUCTIONS
62-0257-11
E4436
T775L Series 2000 Electronic
Stand-Alone Staging Controller
PRODUCT DESCRIPTION
The T775 electronic stand-alone controllers are the next
generation of commercial and agricultural controls
capable of remote sensing of temperature and providing
switched and/or proportional outputs to various types of
loads. A built-in time clock is standard.
The T775L model can be used to stage multiple relays
from two independent heat or cool setpoints. The number
of stages for each setpoint can be freely chosen, limited
only by the number of relays available.
The T775L can be configured with up to two T775S
Expansion Modules for a maximum of up to 12 stages.
IMPORTANT
The T775L is an operating control, not a limit or
safety control. If used in applications requiring
safety or limit controls, a separate safety or limit
control device is required.
Table 1. T775L Controller Configuration.
Controller Model Description Output Reset
SPDT Relay
Outputs
Digital
Input
Sensor
Inputs
Number of
Sensors
Included
Stage
Control
Addable
T775S Enclosure
T775L2007
a
Stage Sequencer
with Reset
Yes
4
b
1
c
21YesYesNEMA 1
a
The T775L model can be used to stage multiple relays from two independent heat or cool setpoints. The number of stages for each setpoint can
be freely chosen, limited by the number of relays available (up to 12 stages using two T775S expansion modules).
In addition to the two staged loops, up to two additional relays can be available for independent on-off control.
b
The maximum number of non-sequenced relays is two (2) with each having its own setpoint and its own throttling range. These relays are
available if not being used by the staged relay loops.
c
The T775L includes a digital input for use with the disable or setback option.

Honeywell T775L Series Specifications

General

Model	T775L Series
Input Voltage	24 VAC
Display	LCD
Enclosure	Plastic
Certifications	UL, CE
Type	Electronic
Input	Thermistor
Output	Relay
Output Type	Relay
Control Mode	On/Off
Communication	Optional
Humidity Range	0% to 95% RH

Summary

Installation Instructions

Product Description

Pre-Installation Checks

Installation Safety and Procedures

Provides essential safety and procedural instructions for installing the T775L controller.

Installation and Setup Guide

Controller Mounting Instructions

Temperature Sensor Mounting and Placement

Controller Wiring Guide

Describes how to access and make wiring connections for the T775L controller and its components.

Temperature Sensor Wiring Details

Controller Wiring Procedures

Controller Wiring Method and Techniques

Controller Terminal Wiring Details

Checkout Procedure

Temperature Sensor Calibration for Accuracy

Explains how to calibrate temperature sensors to compensate for wire length resistance loss.

Controller Programming Overview

Control Loops and Setpoint Configuration

Explains control loops, setpoint, and differential settings for heating and cooling modes.

Understanding Staged Operation

Programming the T775L Controller

Controller Setup Configuration

Guides through changing factory defaults for sensors, outputs, reset, and scheduling.

Setting Up Temperature Sensors

Number of Sensors Configuration

Sensor A Configuration Details

Configures settings for Sensor A, including units, calibration, and labeling.

Sensor Units (°F or °C) Configuration

Sensor Calibration Procedure

Sensor B Configuration Details

Setting Up Controller Outputs

Number of Relays Configuration

Number of Control Loops Configuration

Output Options Configuration

Enable Scheduling Option (USE SCHED)

Digital Input (DI) Options Configuration

Setting Up Control Loops

Number of Relays per Loop Configuration

Loop Scheduling Enable/Disable

Loop Reset Configuration

Setting Up Additional Relays

Relay Scheduling Enable/Disable

Relay Reset Configuration

Exiting Setup Mode

Programming Outputs (No Reset)

Entering Program Mode for Outputs

Program Menu for Outputs (No Reset)

Setpoint Configuration for Loops/Relays

Sets the desired temperature setpoint for loops or relays, defining the target operating temperature.

Throttling Range or Differential Configuration

Sensor, Heat/Cool, and Setback Configuration

Sensor, Heat/Cool, and Setback Configuration

Programming Outputs (With Reset)

Setting Up Controller for Reset Function

Guides through enabling the Reset feature in Setup mode, starting with Loop 1.

Determining and Setting Reset Values

Entering Program Mode (With Reset)

Program Menus for Loops (With Reset)

Setpoint Maximum A1/Boiler Max Configuration

Sensor B Min Setpoint (RESET B1) Configuration

Setpoint Minimum A2/Boiler Min Configuration

Sensor B Max Setpoint (RESET B2) Configuration

Throttling Range Configuration (Reset)

Heat/Cool Mode Selection (Reset)

Loop 2 Programming (With Reset)

Loop 2 Programming (With Reset)

Configures Loop 2 parameters including setpoint offset, throttling range, and heat/cool mode.

Program Menus for Additional Relays (Reset)

Setpoint Offset for Relays (Reset)

Differential for Relays (Reset)

Sensor Selection for Relays (Reset)

Heat/Cool Mode for Relays (Reset)

Exiting Programming (With Reset)

Scheduling Configuration Guide

Creating a Schedule

Guides on how to create or change a schedule by enabling scheduling and setting options.

Entering Schedule Mode

Schedule Options Configuration

Set System Time for Schedule

Set System Date for Schedule

Setting Individual Schedules

Event 1 Schedule Configuration

Event 2 Schedule Configuration

Exiting Scheduling Mode

Troubleshooting Guide

Error and Diagnostic Messages

Explains error codes (EEPROM Failure) and diagnostic messages for sensor issues (Open/Shorted, Out of Range).

Product Specifications

Power, Temperature, and Relay Ratings

Details electrical power, operating temperature, and relay contact output specifications.