4-20ma help
4-20ma help
(OP)
I'm looking to drive a toy train from the analog 4-20 of a slc 500.. So I'm not sure on how to convert 4-20 to 0-12vdc with a 1A load capability. Is there a product out there that will do this? I use I/P at work all the time, but I can't find an I/E in any of our catelogs that will drive that much load. I also thought about using a 0-5VDC card to drive the base of a power NPN transister with 12VDC feeding the collector. If I use the Emitter of the transistor to drive the load will I get a linear drove from 12 to 0 or will it act like an on off switch?





RE: 4-20ma help
xnuke
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RE: 4-20ma help
RE: 4-20ma help
RE: 4-20ma help
RE: 4-20ma help
htt
Scroll down to the bottom of the page, and pick out a
suitable circuit. Sub your derived voltage for the
feedback circuit in the diagram.
There are simpler ways, but I do not have handy examples.
<als>
RE: 4-20ma help
RE: 4-20ma help
You'll have to change the PLC to use 0-20mA so the train will stop.
Feed a 12VDC power supply to the circuit.
Feed 0-20mA into a 600ohm resistor and it is converted to 0-12VDC.
Your output will be 0-12VDC capable of 6.5A.
http://store.qkits.com/moreinfo.cfm/K8004