Programming; Setpoint And Differential; Heating Mode Setpoint And Differential; Cooling Mode Setpoint And Differential - Honeywell T775A/B/M 2000 Series Installation Instructions Manual

T775A/B/M SERIES 2000 ELECTRONIC STAND-ALONE CONTROLLERS

1.PROGRAMMING

The controller must be programmed before being placed
into service.
IMPORTANT
During programming, the controller is live at all
times. For example, the contacts may open and
close when adjusting the setpoint.
The Programming process uses a hierarchical menu
structure that is easy to use. You press the
arrow buttons to move forward and backward through the
menus.
NOTES:
1. The controller interface is intuitive. You may
find that you do not need the following
procedure instructions to program the
controller. You may want to use this
procedure simply as a reference to locate the
particular option or parameter of interest.
2. The menus can display only those relays that
are defined in Setup (See "2.3.2. NBR OF
RELAYS" on page 24). For example, if you
configure only two relays, then only two relays
display on the appropriate menus.
If you press the HOME button or there is no
3.
keypad activity for four minutes, you exit
Program mode and return to the home
screen.
4. If you press the MENU button, you exit
Program mode and return to the menu.

Setpoint and Differential

The following describes the relationship between setpoint
and differential for heating and cooling. These settings are
programmed for each output relay.

Heating Mode Setpoint and Differential

In heating mode, the differential is below the setpoint. The
relay de-energizes when the temperature rises to the
setpoint. As the temperature drops to the setpoint minus
the differential, the relay energizes.
MENU
PROGRAM MOD 1
MOD 2
RELAY 1
RELAY 2
RELAY 3
RELAY 4
EXIT
Fig. 28. Program Menu.
62-0254—13
and
MENU MENU
PROGRAM PROGRAM
OR
RELAY 1
RELAY 2
RELAY 3
RELAY 4
EXIT

Cooling Mode Setpoint and Differential

In cooling mode, the differential is above the setpoint. The
relay de-energizes when the temperature falls to the
setpoint. As the temperature rises to the setpoint plus the
differential, the relay energizes.
Setpoint High Limit
You can set a single irreversible setpoint high limit
maximum value, which is applied to all outputs.
Adjust the setpoint (at any output) to the desired
maximum setpoint. Then, simultaneously press the
home,
, and
buttons for five seconds to set the setpoint high limit
maximum to this value.
NOTE: You must press all three buttons at exactly
the same time for this action to occur.
IMPORTANT
1. This action sets the maximum setpoint value of
all outputs to the setpoint high limit maximum.
2. Setting the high limit setpoint maximum is
irreversible. If you perform the action
inadvertently gently and this setpoint adversely
affects the control of your system, you must
replace the controller.
Programming the T775A/B/M
Controller
To program the controller, perform the following
procedures in the order listed:
1. Enter Program mode — see "1.1. Entering Program
Mode"
2. Program the Outputs — see "1.2. Program Menu for
Outputs"
When programming is complete, you may continue with
"3. SCHEDULING" on page 30 or, for advanced options,
continue with "2. SETUP (ADVANCED OPTIONS)" on
page 17.
1.1. Entering Program Mode
Press the MENU button, then select PROGRAM and
press the button to view the Program menu.
Fig. 28 shows the Program menus for controllers with and
without Modulating Outputs.
NOTE: Modulating outputs are not available on the
T775A and T775B controller models.
M24492
14
buttons and continue to press all three