Power Supply; Configuration Of The Signal Terminals; Configuration Of The Dip Switches; Examples - Becker VARIAIR VAU 4/2 Instructions De Service

3.2 Power supply

It must be made sure that the supply for voltage and current is
dimensioned according to the information on the type plate. 4-wire
copper cable of class 1 for 60 °C / 75 °C are to be used. The
permissible cross-section is stated in the technical data.
The cable bushing for the power supply cable is shown in figure 2 .
The terminal screws have to tightened with a screwdriver observing
the maximum torque of 1.5 Nm.
As an additional protection a fault voltage circuit breaker or a protec-
tive grounding could be installed. Fault voltage circuit breakers are
not suitable for the use of VARIAIR converters due to possible DC
loads .VARIAIR converters cause an operational leakage current via
the protective conductor of more than 3.5 mA. That is why one of the
following conditions must be fulfilled:
· Cross-section of the protective conductor at least 2.5 mm²
· Monitoring of the protective conductor by a device which leads to an
automatic shutting off of the converter in case of an error.
· Laying of a second conductor parallel to the protective conductor
via separate terminals. This conductor must meet the requirements
according to DIN VDE 0100 part 540 for protective conductors inde-
pendently.
(Symbol) Control and power supply cables must be
guided and laid separately.

3.3 Configuration of the signal terminals

Functional characteristics of the control inputs and outputs
4-channel block of binding posts:
SSM - collective error message
This relay is set as break-contact and is activated if the converter is
in error mode.
SBM - collective operating message
This relay is set as make-contact and is activated if the converter is
in operating mode
9-channel block of binding posts:
1 - 24 V power supply
This output can be used for activating of the digital inputs or to supply
external sensors. The maximum admissible current is 50 mA.
2 - Release of the converter (Start / Stop)
This digital input no.1 releases the converter. The input has a Start /
Stop function. In normal operation 24 V are required here.
3 - Analogue output for 0 to 10 Volt
The voltage is proportional to the actual speed of the pump or the
fan.
4 - RS485 interface Data +
5 - RS485 interface Data -
6 - Analogue input 2 (-10 V +10 V)
This input can be used as an input for a sensor signal.
7 - Analogue input 1 (0...10 V or 0...20 mA)
This input can be switched to a control signal with a voltage of 2 to 10
Volt or a current of 0 to 20 mA.
The switching can be carried out by the Service department of
Gebrüder Becker.
8 - 10 V Reference voltage output
This output produces a voltage of 10 V in order to directly connect
an external potentiometer (no protective resistor is necessary).The
maximum admissible current is 10 mA.
9 - Signal grounding
The signal grounding is isolated from the power supply. All potentials
of the control signals are related to this grounding.
Figure 3 Terminal designation
480 V +/- 10%

3.4 Configuration of the DIP switches

1: OFF: speed adjusting operation
ON: controlled operation
The standard option of the frequency converter is the PID control. The
adjustment of the control to internal control is done by the Service
department of Gebrüder Becker
2: OFF: RS 485 - interface in BIKOM mode
ON: RS 485 - interface in SAS -listing mode
With the DIP switch 2 you can switch BIKOM and SAS listing mode
if you use the interface.
3: OFF: set-point source installed potentiometer
ON: set-point source analogue input 1
In the OFF position of the DIP switch 3 the control of the converter is
effected by an external control signal.
4: OFF: fan in pressure operation
ON: pump in vacuum operation
With the DIP switch 4 the operation mode of the fan or the pump
can be set.

3.5 Examples

3.5.1 Potentiometer connection

Figure 4 Potentiometer connection
Analogue input 1 in 0 ... 10 V mode
Ω
To use it the DIP switch 3 must be set to ON. This defines the
analogue input 1 as the set-point source at terminal 7.
Terminal 8 gives the 10 Volt power supply and terminal 9 the signal
grounding. Also compare Chapter 3.3 and Chapter 3.4.