DNS-24, DNT-T103 & DNT-T221 Application Guide
Page 34 of 43
Document Edition 4.2
When the application is set to HPU on a DNT-T103 and the fan type is
Intermittent
, the fan will start
when the compressor starts. When the compressor stops and the
Output 3 Binary Delay
(AV28) has
timed out, the fan output will be turned off. [Only exists in Release 2 Firmware and higher.]
N
OTE
:
For fan-powered boxes series fans should always be configured for continuous
operation – 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.
6.
A
NALOG
(DNT-T221
O
NLY
)
Only the DNT-221 supports two analog outputs, which provide a 0 to 10v signal. Selecting Outputs 1
&2 as analog are not even options in the Configuration Menu for the DNT-T103.
For VAV and VVT, Output 1 is configured as an analog damper (flow for VAV and cooling for VVT).
The other analog output may be configured as a modulating output for auxiliary heating or cooling. Due
to the internal controller logic, an analog flow damper also requires that an appropriate runtime be set
for the actuator (via Setup variable AV24), which is set to control the speed with which the damper will
move and needs to be equal to or greater than the actual run time of the analog actuator. Analog outputs
for auxiliary heating or cooling do not have an associated runtime setting.
If the application is something other than VAV or VVT, then both analog outputs may be configured
for either heating or cooling. Analog outputs for heating or cooling may be either direct or reverse
acting.
For the HPU application, 2-position control is provided for the compressor and reversing valve, 0 or 10v
(typically requiring an appropriate interface relay), rather than modulating the two analog outputs.
OWS Functions
1.
D
EVICE
C
ONFIGURATION
The BACstat can be configured and commissioned using the keypad buttons, via the Configuration
Menu, without additional software. It can also be configured using the ORCAview OWS if the BACstat
is connected to an MS/TP network.
However, to do this requires a minimum configuration for each device to ensure they are all configured
the same and are communicating properly on the designated network. These essential configuration
items include:
N
ETWORK
C
ONNECTION
: LINKnet O
FF
(MS/TP).
DNA: O
N
or O
FF
D
EVICE
A
DDRESS
: 1-99 for MS/TP
B
AUD
R
ATE
: Set the speed to match the network it will be
connected
to (76,800
bps is the default)
Configuration Settings
When the ORCAview OWS is able to access the BACstat and its objects, you may then configure the
following BACstat settings at the OWS (which are usually configured once and rarely ever changed
thereafter). However, these
must
be configured in the sequence provided (which is the same as the
Configuration Menu). Any change to these settings from an OWS requires the BACstat to be reset
(locally or via user command).
A
PPLICATION
:
AV12 (refer to page 13)
O
UTPUT
C
ONFIGURATION
1: AV21 (refer to page 30, and associated Application
information)
