TC-Standard (+)
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 appears, please refer to bullet “Troubleshooting”.
Please refer to the data sheet for performance data and maximum ratings.
5.1 Description of functions
The cooler is controlled by a microprocessor. With the factory preset the control already incorporates the various characteristics
of the built-in heat exchangers.
The programmable display shows the block temperature in the selected display unit (°C / °F) (factory preset °C). Application-spe-
cific 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 2 to 20 °C (36 °F to 68 °F) (factory preset 5 °C/41 °F).
And then the warning thresholds can be adjusted for low and excess temperature. These are set relative to the outlet dew point
τ
a
setting.
For the low temperature the range is
τ
a
-1 to - 3 K (at a minimum 1 °C/ 34 °F cooling block temperature), for the excess temperat-
ure the range is
τ
a
+1 to +7 K. The factory presets for both values are 3 K.
The flashing display and the status relays indicate the conditions are below or above the configured warning range (e.g. after
switching on).
The status output can e.g. be used to control the sample gas pump to allow for the gas flow to only be switched on once the per-
missible cooling range has been reached or shut off the pump in the event of a moisture detector alarm.
The separated condensate can be drained via connected peristaltic pumps or add-on automatic condensate drains.
Fine mesh filters can also be used, which in turn can be installed in optional moisture detectors.
The glass dome allows the dirt level of the filter element to easily be determined.
The moisture detector is easy to remove. This may be required if a condensate enters the cooler due to a malfunction and the
peristaltic pump or the automatic condensate drain is unable to remove it.
5.2 Delta T control option
Not all applications require an outlet dew point of 5 °C (41 °F). In some applications a higher dew point is sufficient. In other ap-
plications a stable outlet dew point doesn’t matter, it’s enough for the gas to be dry, so if the outlet dew point has an adequate
difference in temperature below the ambient temperature.
Here the electronics measure the ambient temperature and regulate the outlet dew point to an adjustable value below it. This
extends the potential cooling capacity to the limits of the heat exchanger. Here it’s important to note the outlet dew point fluc-
tuates along with the ambient temperature and a stable dew point cannot be a prerequisite for the measurement.
The target temperature range is defined by the ambient temperature, the adjustable temperature difference and the alarm lim-
its. If the block temperature is not within the target range with active Delta T-control, the status message "
dt
" will flash in the
display.
Example:
At a difference of 30 °C (30 K/54 °F), at a set outlet dew point of 5 °C (41 °F) this means the dew point remains stable up
to an ambient temperature of approx. 35 °C (95 °F), and the safe drop is only preferred over the ambient temperature with ambi-
ent temperature peaks over 35 °C (95 °F). The cooling capacity specified in the cooling capacity graphs at 35 °C (95 °F) is then
available at above 35 °C (95 °F).
15
Bühler Technologies GmbH
BE440026 ◦ 12/2020