4-20ma signal
4-20ma signal
(OP)
I have a project that will require a second 4-20ma signal
for recording! The signals as of now goes to a PLC. I would like to get a second signal to run a logging system and use the same currant signal.
for recording! The signals as of now goes to a PLC. I would like to get a second signal to run a logging system and use the same currant signal.





RE: 4-20ma signal
Keith Cress
Flamin Systems, Inc.- http://www.flaminsystems.com
RE: 4-20ma signal
Each receiver device's analog input has a resistor that converts the current to a proportional voltage.
Two receiver devices can be run in series if the combined loop resistance does not exceed the capacity of the source to drive the loop. Since most inputs do not take more than 250 ohms, it's likely you could run the inputs in series.
If the source is an active output (powered internally) wire it:
source + to input 1 +
Input 1 - to input 2 +
Input 2 - to source -
If the source is loop powered (external power supply) then wire it:
power supply + to source +
source - to input 1 +
Input 1 - to input 2 +
Input 2 - to power supply -
Dan
RE: 4-20ma signal
rmw
RE: 4-20ma signal
I have used these in many places with excellent results.
Joe
RE: 4-20ma signal
"..the more, the merrier" Genghis Khan
RE: 4-20ma signal
RE: 4-20ma signal
RE: 4-20ma signal
A signal transducer as suggested by dcasto is likely your best option, however check the power source. 2-wire signal transducers may require power source on the input or output side of the transducer.
As an alternative you can always take an output from your PLC and connect it to your recording loop. This would minimize your installation costs as you would not have to purchase additional components and nothing extra to install other than wire.
RE: 4-20ma signal