how to connect a vm140 input from/to a K2649
tks
Terminal block J2 is the output of the K2649.
Connect terminal “C” to “GND” of the VM140.
Connect terminal “NO” to the digital input of the VM140.
super merci
may i ask again ?
how ( where to do the correct connexions ?) to connect a k2649 to an analogique input of a VM140 in order to also monitor the historic temperature graph on a PC ?
tks a lot for your usal powerfull help.
I think there at the output of the operational amplifier A1 is voltage proportional to the temperature.
In the circuit diagram this point is the common point where the resistors R17, R20 and the A1 output are connected.
If you connect this point to the analog input of the VM140 and the ground of the board (e.g. minus of C1) to the GND terminal of the VM140, you may get some readings proportional to the temperature.
Much better solution to get temperature readings is to use the Universal Temperature Sensor kit K8067:
velleman.eu/distributor/prod … ?id=354616