Controller and Recorder in Series

If your transmitter (TX) is self-powered, this will work. Otherwise, you'll have to connect a 24Vdc power supply to the loop.

Next question: what's the input requirement for the recorder (in volts or millivolts). With a 10Ω resistor, your voltage at the recorder's input will be 0.04 to 0.2 volts. If this is what you need then there's no problem. If it's not, you'll need to change it.

Vmin = 0.004 × R

Vmax = 0.02 × R

regards,

Vulcan

thank u so much!

UDC controller and TVMQX are configreated as current input, so all what care me is to get 4-20 mA to these devices

THANX

If both the load devices are both 4-20mA input then omit the parallel resistors, otherwise the readings will be in error on the low side.

thnx for reply

UDC controller and TVMQX recorder catalogs show that resister must be installed at controller pins when configruted as currunt input (250 ohm for controller) and 10 ohm (for recorder)

In that case the controller is actually 1-5V input and the recorder is 40-200mV input. It is the external resistors, in this case, that determine the match of each device to the loop.

If this is the case, then the sketch is correct, though it is worth double-checking.