RS232 to 4-20ma Transmitter
A couple of years ago, we did a job at the Denver Zoo where they wanted an AMX control system to control a waterfall. The waterfall operation was controlled by a PLC and they wanted our AMX system to communicate with the PLC over a 4-20ma current loop, very common for PLCs. That gave us the idea for this device. It lets an AMX master (or any device with a RS232 port) control the current in a 4-20ma loop. The protocol is very simple and generally the current is less than +/- 0.005ma difference from the desired current; at worst it is +/-0.01ma.
Click on the image above for a larger view. Click on this link for the manual for this device: RS232 to 4-20ma Tx Manual
- RS232 to 4-20ma Transmitter – $245.00