Signal Outputs - Bühler Technologies Rc 1.1 Kurzanleitung

RC 1.1, RC 1.2+
Plug numbering
Status output S2 *
*
Digital output S4
1 - not used
2 - RS485 A
3 - GND/Common
4 - RS485 B
5 - Shielding
Fig. 1: Cooler connection
* When using the status output with a voltage ≥ 33 V AC or ≥
70 V DC, the protective earth (PE) must be connected.
The clamping range has a diameter of 8–10 mm (0.31–0.39
inch).

4.4 Signal outputs

The device has various standard and optional signal outputs.
Signalling via the display and the status output are always in-
cluded in the scope of delivery. An analogue or digital output
is optional.
4.4.1 Signalling via the display
The front foil contains three LEDs:
Colour Marking Function
Red S2 High/low temperature, device error
Yellow S1 ---
Green OP Normal operation
The OP and S2 LEDs indicate the device status in the same way
as status output S2.
4.4.2 Status output (terminal S2)
The maximum switching capacity of the status outputs is
250 V AC / 150 V DC, 2 A, 50 VA each.
The status output (S2) indicates when the cooler block tem-
perature is outside the specified limits. No distinction is made
as to whether the alarm was triggered by excess temperature
or insufficient temperature.
If the "humidity sensor" option is installed, status output S2
will also signal if moisture is still present in the conditioned
sample gas or if a cable break is detected. The signalling does
not distinguish between humidity sensor 1 or 2.
16 Bühler Technologies GmbH
Electric supply S1
Analogue output S3
1 - N/C
2 - N/C
3 - GND
4 - 4-20 mA out
5 - shield
Function / Description
contact type
internal the following
changeover device statuses
contact: max. can be indicated
250 V AC / via two switching
150 V DC, 2 A, outputs:
50 VA
4.4.3 Analogue output (connection S3)
If the 'analogue output' option (see type code) is integrated,
the actual value of the cooler block temperature is output via
the analogue output as a 4...20 mA signal.
The device menu offers the option to reconfigure the interface
from current output to voltage output. The analogue value is
then represented as a 2...10 V signal.
The temperature signal can be tapped via the built-in con-
nector (S3) with M12x1 connection. This connector is located
next to the connections for the humidity sensors on the top of
the cooler.
Function / contact Description
type
4-20 mA analog Signalling of the
output cooler block tem-
(R <500 Ω) perature
load
Contact between 3 and 2
closed (alarm)
• No mains voltage and/or
actual temperature
value outside the set
alarm thresholds.
• Device in fault condi-
tion / pump deactivated.
Contact between 3 and 1
closed (ok)
• Mains voltage applied +
actual temperature
value within the set
alarm thresholds.
with humidity sensor option
Contact between 3 and 2
closed (alarm)
• Humidity sensor detects
residual moisture in the
sample gas or cable
break: Error message.
Contact between 1 and 3
closed (ok)
• No residual moisture in
the sample gas / no
cable break.
T = -20 °C ≙ (-4 °F) ->
cooler
4 mA/2 V
T = 5 °C ≙ (41 °F) ->
cooler
9 mA/4.5 V
T = 60 °C ≙ (140 °F) ->
cooler
20 mA/10 V
BX450039 ◦ 08/2025