6.13 1 analog ADC input (ADC)
This is another analog ADC input similar to the T1 and T2 input for the temperature sensors. In case a
set limit value (in mV) is exceeded or undercut, the module may automatically return an SMS, a FAX or
am e-mail with the entered message text. This input is able to measure a voltage of between 0 V to 2V.
If the limit value is to be set to e.g. 1.2 V, you must enter 1200 at limit value.
This is intended e.g. for an analog fill level indicator; the module can issue a warning message before the
storage container runs empty or flows over. For limit value definition, you can fill the container to the
desired level, read off the value in status and enter this as limit value in the software.
No output can be switched.
6.14 2 temperature inputs (T1-T2) /
4 temperature outputs (TMP1-TMP4)
Two temperature sensors (Conrad order no. 198896) can be connected to the two temperature inputs T1
and T2. The positive pole is connected to the left screw clamp, the signal in the middle and the ground is
connected on the right screw clamp. The temperature range of the sensor ranges from -40? to +125°C.
The input T1 must be selected if only one temperature sensor is used. 0°C is output if no sensor is con-
nected. The outputs TMP1 to TMP4 are logically linked with the temperature control. You can directly
connect a relay to these outputs (CONRAD order no. 502892).
There are two different types of operation: range measurement and difference measurement.
RANGE MEASURING: You can set a MAX, MIN and a TARGET temperature value for both temperature
sensors. The TARGET value is the defined temperature. If the MAX value is exceeded, output TMP1 or
TMP3 is activated automatically (e.g. for a ventilator) until the temperature undercuts the TARGET value
again. If the MIN value is undercut, the output TMP2 or TMP4 is activated (e.g. for a heater) until the
TARGET value is exceeded again. This generates a hysteresis that prevents the outputs from switching
on and off in turn all the time.
Example: If you set the MIN to 20°C, the TARGET to 25°C and the MAX value to 30°C), the output
TMP1 is switched on when exceeding the MAX value (31°C) and switched off when reaching the TAR-
GET value (25°C). The output TMP2 is switched when the temperature drops below the MIN value
(19°C).
DIFFERENCE MEASURING: In this case, only the temperature difference is controlled (e.g.
forward/backward flow of a heater), meaning there is no TARGET temperature. As soon as the differ-
ence (T2-T1) exceeds the MAX value, the output TMP1 switches; if the difference (T2-T1) undercuts the
MIN value, the output TMP2 switches. TMP1 and TMP 2 are switched off as soon as the temperature dif-
ference is again within the MIN and MAX range. TMP3 and TMP4 are not switched here.
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