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7.4 Control signal
As described in the „Unit Control“ chapter,
section „Provider level submenue and its
parameters“, the unit control type is deter-
mined by parameter „1-2“, „control signal“. In
accordance with the control type selected,
terminal wiring of the connection terminal (s.
„Unit control“ chapter, section „Main PCB
connections“ is to be made.
7.4.1 1-step operation
Steam humidifier operation is controlled by
the contact across terminals 3 and 5 provided
by the customer. This contact needs only to
be low voltage proof.
7.4.2 Operation with an active humid-
ity sensor or external controller
When driving the steam humidifier by an
active r.h. sensor or external controller (e.g. a
PLC), control signals in the range of 0...10 V,
0...20 mA or 0...140 Ohm may be applied.
Each one of the signal types is connected to
a dedicated terminal (see „Unit control“
chapter, section „Main PCB connections“).
Reference is always to terminal 4, GND.
Active r.h. sensors need an external supply
voltage. For that purpose, terminal 3 has a
+20 VDC offering.
7.4.3 Wiring for control signal and
safety (interlock) system for
multiple units
In the case of multiple units, separate humidi-
fiers work together. The control signal and
the safety (interlock) system are connected
to the master unit as described above. In
addition, connecting cables are established
between the guiding unit and the successing
unit(s) (provided on-site). These provide the
successing unit with a control signal from the
guiding unit and the transmitted (potential
free) safety (interlock) system.
The wiring for the control signal and the
safety (interlock) system must be imple-
mented as follows for multiple units:
1)
„ST0x“ designates connector plugs on the mainboard
2)
„K21“ is the relay used for the connection of the suc-
cessing unit
3
45
6
7
20 VDC
Customer-provided contact
for 1-step operation
3
4
5
6
7
20 VDC
GND
0...10V
0...20mA
Terminals for
control signals
0...140 Ohm
Please note
3
45
6
7
+20 VDC
Humidity sensor
Terminal strip
GND
0...10V
Exemplary 0...10V humidity
sensor connection
1)
2)
12 13 11 14
5 4 1 2
ST07
K21
ST08
ST01
1)
1)
Guiding unit
Successing unit
