I have connected the ITP11 but it doesn’t switch on, what should I check?

First of all, check the polarity of the signal.

Also, make sure that the 4-20 mA signal is available. If the signal is too low (< 3.8 mA), there is not enough power to switch on the process display.

Check the wiring. A wire may be loose or not connected to the terminals.

Check the transmitter output. If the output is passive, you need an auxiliary voltage supply.