RC 1.1, RC 1.2+
4.4 Signal outputs
The device provides different status signals. The maximum
switching load of the alarm outputs is limited to
250 V AC/150 V DC, 2 A, 50 VA each.
An alarm is triggered by the alarm contact/status output (S2)
if the temperature of the cooler is outside the specified limits.
It does not indicate if the alarm was triggered due to excess
temperature or insufficient temperature.
The front film has three LEDs:
Colour
Marking
Function
Red
S2
High/low temperature, device error
Yellow
S1
---
Green
OP
Normal operation
The LEDs OP and S2 indicate the device status similar to S2.
If the option "temperature signal" is built in, the unit has a
signal output via the analogue output to indicate the actual
cooler temperature.
When the moisture detector (optional) is installed, an alarm is
activated by the alarm contact/status output (S2) if the mois-
ture is still present in the prepared sample gas. Thereby, no
distinction is made between the alarm/cable break triggered
by moisture detector 1 or 2. This information is displayed by
an error message instead.
The temperature signal can be read via the panel plug (S3) us-
ing the M12x1 connector. This plug is located next to the mois-
ture detector connectors at the top of the cooler.
Description of signal outputs
Function/
Description
contact type
Re-
internal
the following
gar
changeover
device
d-
contact:
statuses can
ing
max.
be indicated
S2)
250 VAC/150
via two
VDC, 2 A,
switching
50 VA
outputs:
14
Bühler Technologies GmbH
Contact between 3 and 2
closed (alarm)
• No mains voltage and/or
actual temperature out-
side the alarm
thresholds
Contact between 3 and 1
closed (OK)
• Mains voltage attached
+ actual temperature
within the alarm
thresholds
With moisture detector op-
tion
Contact between 3 and 2
closed (alarm)
• The moisture detector
registers residual hu-
midity in the sample gas
or cable break: Error
message
Contact between 1 and 3
closed (OK)
Re-
4-20 mA
Signalling of
gar
analogue
actual tem-
d-
output
perature
ing
(R
<500 Ω
Load
S3)
)
Re-
Digital out-
Modbus RTU
gar
put
(RS-485)
d-
ing
S4)
5 Operation and control
NOTICE
The device must not be operated beyond its specifications.
After switching on the cooler the block temperature will be
displayed. The display will flash until the block temperature
has reached the preset target value (± adjustable alarm
range). The status contact is in the Alarm position.
Once the target temperature range has been reached, the
temperature will continuously be displayed and the status
contact switches over.
If the display flashes during operation or an error message ap-
pears, please refer to bullet "Troubleshooting".
Please refer to the data sheet for performance data and max-
imum ratings.
5.1 Description of functions
The cooler is controlled by a microprocessor. With the factory
preset the control already incorporates the various character-
istics of the built-in heat exchangers.
The programmable display shows the block temperature in
the selected display unit (°C / °F) (factory preset °C). Applica-
tion-specific settings can easily be configured guided by the
menu, using the 5 buttons. For one, this applies to the target
outlet dew point, which can be set from 3 to 20 °C (factory pre-
set 5 °C).
And then the warning thresholds can be adjusted for low and
excess temperature. These are set relative to the outlet dew
point τ
setting.
a
For the low temperature the range is τ
imum 1 °C cooling block temperature), for the excess temper-
ature the range is τ
+1 to +7 K. The factory presets for both val-
a
ues are 3 K.
The S2 LED and the status relays flashing indicates the condi-
tions are below or above the configured warning range (e.g.
after switching on).
• no residual moisture in
measuring gas/no cable
break
With temperature signal op-
tion
T
= -20 °C ≙ (-4 °F) ->
cooler
4 mA/ 2 V
T
= 5 °C ≙ (41 °F) -> 9 mA/
cooler
4.5 V
T
= 60 °C ≙ (140 °F) ->
cooler
20 mA/ 10 V
Interface default values
Baudrate – parity – stop bit:
19200 – Even – 1
Default ID: 10
The bus lines are not intern-
ally terminated.
-1 to - 3 K (at a min-
a
BX450028 ◦ 09/2021