DNS-24, DNT-T103 & DNT-T221 Application Guide
Page 24 of 43 Document Edition 4.2
3. VVT ā [Application (AV12) = 2]
Function: Control of a simple VVT box with a Tri-State damper on Outputs 1 and 2 (for DNT-T103) or
an analog damper on Output 1 (for DNT-T221), and various options on the remaining outputs (of which
some options are no longer available in Release 3 firmware).
DNT-T103 I/O (Outputs 1 to 3 are Triacs)
Tri-State
Damper - Cool
(Open)
Tri-State
Damper - Cool
(Close)
Tri-State
Damper - Cool
(Open)
Tri-State
Damper - Cool
(Close)
Tri-State
Damper - Cool
(Open)
Tri-State
Damper - Cool
(Close)
DNT-T221 I/O (Outputs 1 & 2 are Analog, and Output 3 is a Triac)
Analog Damper
(Cooling 1)
Analog Damper
(Cooling 1)
Analog Damper
(Cooling 1)
Analog Damper
(Cooling 1)
Analog Damper
(Cooling 1)
NOTE: For fan-powered boxes series fans should always be configured for continuous
operation ā never intermittent or the fan could run backwards on startup. And, in order for
a parallel fan to be properly sequenced it should generally be configured as the 1st stage of
heating (and wired to OP1), rather than as a fan.
Setup Parameters
Damper Runtime (Tri-state or Analog)
PWM minimum value or Binary On Delay
(or Binary Off Delay for a Fan)
Depends on OP3 configuration
PWM maximum value or Time Proportioned
Heating Controller Limit
Depends on OP3 configuration