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This completes the programming procedure for
controllers that do not use Reset.
3. PROGRAMMING OUTPUT
(LOOPS AND ADDITIONAL
RELAYS) WITH RESET
The T775L can be programmed for Reset or No Reset for
each output. From the factory, the T775L is programmed
for No Reset. This section describes the steps necessary
to program the controller for Reset.
SETUP
OUTPUTS
LOOP 1
RESET
Fig. 59. Reset Setup.
Determining and Setting the Reset
Values
NOTE: When using the Reset feature, Sensor A must
be sensing the controlled temperature (e.g.
Boiler), Sensor B must be sensing the resetting
temperature (e.g. outdoor temp).
To program an output (loop or relay) for Reset, refer to the
values as shown in the examples below and in Fig. 60.
Choose your own appropriate values for Sensor A
maximum and minimum and Sensor B maximum and
minimum.
Reset Example:
• Sensor A is the boiler sensor and Sensor B is the
outdoor sensor.
• Maximum boiler temperature desired is 210°F when
the outdoor temperature is 20°F.
T775L SERIES 2000 ELECTRONIC STAND-ALONE STAGING CONTROLLER
SETUP
OUTPUTS
LOOP 1
RESET
YES-BOILER
YES-OTHER
NO
USE
RESET
FOR
LOOP 1
(see Fig. 60)
To use the Reset feature, Loop 1 must be set to
Reset=YES in Setup mode (see "3.1. Setting Up the
Controller for Reset"). The reset curve established when
programming Loop 1 is then used for the second Loop
and the additional relays.
The reset curve established when programming the first
Loop is then used for all subsequent Loops and any
additional relays that are configured for Reset, and each
of those outputs will be offset from this curve.
For all outputs that will follow a reset curve, be sure to
configure for Reset=YES in the setup mode. Choose
Reset YES or NO for all other outputs you wish to reset,
then press the HOME button to record your selection.
3.1. Setting Up the Controller for Reset
1. Press and hold MENU for five seconds to enter
Setup mode.
2. Then choose:
OUTPUTS
LOOP 1
RESET
then select YES-BOILER or YES-OTHER (Fig. 59).
You can now press the HOME button to exit Setup mode
and continue with "Determining and Setting the Reset
M24402
Values".
• Minimum boiler temperature desired is 160°F when the
outdoor temperature is 70°F.
• With the above settings example, when the outdoor
temperature is 50°F, the effective setpoint is 180°F.
Setback (optional) Example:
• Setback of -10°F is used to drop the temperature at
night by 10°F.
• With the above settings example, when the outdoor
temperature is 50°F, the effective setback setpoint is
170°F (180°F setpoint minus the 10°F setback).
NOTE: A single reset curve is programmed for the first
output and is used by all outputs and loops setup
with RESET=YES.
NOTE: For subsequent outputs (Loop 2 and Relay), a
setpoint offset is used if that output is also being
Reset. See "3.4.1. SETPOINT OFFSET (Loop 2
only)" on page 29.
When Reset is programmed, the home screen (Fig. 15 on
25
(see Fig. 60)
62-0257—11
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