Application Integration
PTU 025 is designed for central air handling units with 1 or more filters in the inlet/outlet part and with fan control based on the
airflow or pressure level in the ventilation system. Separate frequency converters with separate pressure transmitter units control
the inlet and outlet. PTU 025 has 4 pressure inputs. See the pressure ranges in
Table 1.4
. Sensors 3 and 4 can be configured for
either filter monitoring or PID control of the airflow or the pressure level.
Illustration 1.10 Application Integration Example
#
Range
Typical function
1
0–500 Pa
Filter monitoring
2
0–500 Pa
Filter monitoring
3
0–1000 Pa
Filter monitoring or PID control of the airflow or the pressure level
4
0–2500 Pa
Filter monitoring or PID control of the airflow or the pressure level
Table 1.4 PTU 025 Sensors and their Functions
Integrating pressure signals into a system solution
The pressure values can be read as analog values on the
analog output or as pulses on digital outputs. Use
parameter 5-30 Terminal 27 Digital Output
,
parameter 5-31 Terminal 29 Digital Output
, and
parameter 5-40 Function Relay
to send the sensor status to the
relay or digital outputs. For more information about using the
pressure values in applications and in the smart logic control,
see the
programming guide
.
PID closed-loop control based on the airflow or pressure
level
Use parameters in
parameter group 20-0* Feedback
to use the
pressure values for the frequency converter’s closed-loop PID
controller.
Use parameters in
parameter group 22-** Application Functions
to configure the monitoring of HVAC applications based on
airflow. For more information, see the
operating guide
and the
programming guide
.
Installation Instructions
Pressure Transmitter Unit PTU 025
VLT
®
HVAC Drive FC 102
MI08A102
Danfoss A/S © 12/2017 All rights reserved.
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