0
\$\begingroup\$

I do have 2 proximity sensors (level sensors) with 3 wire design. They offer to be PNP or NPN and I need to implement them into an RS-232. They are supplied by 24 VDC. Is there somewhat like a commercial converter which can do this?

The parts will be build in as liquid level sensors and the communication within all the system is RS-232 based. I just want to get "a signal" from that channel if the sensor switches from on to off or vice versa. The signal should be continuous.

\$\endgroup\$
4
  • \$\begingroup\$ What is the sensor connecting to? RS-232 defines the interface - how the information is transmitted - but not what information is transmitted. \$\endgroup\$
    – vir
    Commented May 7 at 16:04
  • \$\begingroup\$ I basically need exactly this ;) The sensor is not connected to anything and I basically need "the missing link" in between. Problem is, it is powered by 24 V and forwards this power. I imagine a A/D converter would do the trick, but I only found ones for 10 V... \$\endgroup\$
    – Kinetik1703
    Commented May 7 at 16:10
  • \$\begingroup\$ So correct me if I'm wrong, but you have a sensor (2 of them) which has 3 wires: GND, 24V, and OUT. The OUT is either an NPN or PNP output. You need to use RS-232 to read this output? So ie if you connected OUT to a chip which read the signal logic and then communicated that back to an MCU using RS-232? \$\endgroup\$
    – InBedded16
    Commented May 7 at 17:17
  • \$\begingroup\$ Can your receiver understand the RS232 handshake signals CTS and DSR? They can be used as static inputs \$\endgroup\$
    – Jens
    Commented May 7 at 22:48

1 Answer 1

Reset to default
0
\$\begingroup\$

Basically you need some remote GPIO. The simplest option is to use a microcontroller like an arduino. Not only is it cheap and simple, but it gives you extreme flexibility in terms of the protocol used to transmit the state over the RS-232 link.

If you really do need RS-232 signal levels (useful for long wires). You can incorporate a TTL to rs232 level shifter.

\$\endgroup\$

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.