Rev. 1 - 05/10/2021
OPERATING MANUAL
OPERATING MANUAL
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9.6.3.3 Enable Signal (for RDP 2.65kW - 5.5 kW 3-Ph only)
The ENABLE signal allows the installation of
the Start/Stop switch.
The fan runs when the ENABLE input is con-
nected to the +10V or +24V power supply.
The status of the ENABLE input does
not affect the Modbus Temporary
modes.
9.6.3.4 Pressure and flow meter (for RDP 2.65kW - 5.5 kW 3-Ph only)
To provide a constant airflow, it is possible to order the RDP fan
provided with the optional Volumeter pressure probes, which
are then connected to transducer K43198 by means of K409A2
piping. This transducer is connected to the PID regulator incor-
porated into the driver, which is installed on the fan.
The pressure transducer should be connected with volumeter
pressure probes on the RDP fan provided as a factory installed
option.
For a correct installation, follow the instructions supplied
with the single components.
If it is not necessary turning on/off the fan with an external switch, a jumper can be inserted between clamps
+24V and ENABLE. In case this jumper is not included, the fan will not start.
For further details, refer to par. 13.3.
The voltage provided on the “Enable” input is
constantly measured in all the driver operat-
ing modes, and the value can be read in the
Input Register 28.
The voltage provided on the Enable input
does not affect the four “Modbus - Temporary” modes, where the fan is intended to be completely controlled,
including its starting and stopping, via its serial interface.
This voltage is relevant in all the other operating modes: the modes relying on target values stored in fixed
registers (Modbus – Fixed values) and the modes where an Analogue Input signal is used, plus the Master/
Slave mode.
In those modes which are sensitive to the Enable input, the fan starts only if the voltage on the Enable channel
is above 5 V and stops when it’s brought to zero. An internal pull-down resistor brings the voltage to zero, if
no voltage source is connected to the Enable channel.
This function cannot be disabled by software, but the Enable channel can be permanently connected with a
jumper to either one of the internal voltage-sources: 10 V or 24 V.
When the Analogue Input signal is used, the driver needs both the digital input on the Enable channel and
a signal higher than 0.5 V on the Analogue-Input channel, to start. In these modes, the fan can be stopped
by removing the voltage on the Enable channel, by bringing the Analogue Input voltage below 0.5 V, or both.