S&P VFTM Series, Manual

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ENGLISH
4.3 PI CONTROL IN CONSTANT PRESSURE / AIRVOLUME SYSTEMS WITH AN EXTERNAL ANALOGUE
SENSOR AND 0-10V SENSOR
4.3.1 Features
Constant Air Volume (CAV)
The inverter is used to guarantee a specific air volume in a duct system, regardless of filters clossing.
Constant Pressure (COP)
The inverter is used in variable airvolume systems to guarantee specific air pressure in the duct system,
regardless of whether the dampers are open or closed.
In both cases, the pressure must be constant in the duct system. The value of this pressure must be determined
by experimenting during the system start-up process.
A TDP-D differential pressure sensor with display is necessary to start up this system.
The first attempt at making the adjustment will be by changing the sensor range. The established pressure values
are:
Value entered
“rPI”
Pressure to be maintained
in duct system (Pa)
0-100 50
0-150
75
0-300 150
0-500 250
0-1000 500
If none of the values in the table above is suitable for the installation, you must establish the exact pressure
setting by re-configuring the frequency inverter. (see point 7.3.)
4.3.2 Installation diagram
Constant Pressure Installation Diagram
+ -
SONDA DE
PRESION TDP
VENTILADOR
VARIADOR
DE
FRECUENCIA
FILTRO
FILTER FAN
TDP PRESSURE
SENSOR
FREQUENCY
INVERTER