Hello All,

I am looking for a 4-20 mA signal duplicator. What I need is a device with a 4-20mA input and two outputs with 4-20 mA. the input will go equally to the outputs. If anyone can help me, will be much appreciated.

 

Just as a disclaimer, I don't use 4-20mA devices, but aren't they a loop by nature? This would imply that you can have one output sourcing current to "n" input devices in the current loop. Am I missing something? (This is entirely possible!)

)

~KEJR

 

Can you simply put the two inputs in series? If not, you can use two signal conditioners with their inputs in series and the outputs to your loads.

Regards
cww

 

Hi there,

Omniterm LPS
Model C2464B
DIN rail mount Current Loop Splitter (24Vdc powered)

http://www.omniflex.com/otloopisolators.asp

 

You can use multiple devices on a single 4-20mA loop. For example you can have a local display unit and also input into a PLC or DCS. However you could run into issues if you have too many devices on the loop or the sourcing device isn't capable.

You may need a splitter or signal isolator:
http://www.phoenixcontact.com/signal-level-matching/31244_14827.htm

Look for "Signal Splitter, Configurable" MCR-FL-C-UI-2UI-DCI

Chris Jennings

 

Here's a splitter:
Phoenix Contact Universal signal splitter
single 4-20ma input
dual 4-20mA output

http://rd.phoenixcon.com/products/interface/db/datasheets/MCR-2UI.pdf

Yes, technically a current source device can drive two receiver devices in its loop, if the combined resistance is low enough (it usually is) and if the grounding sorts itself out(dicey).

The problem with grounding is ground loops. Grounds at different potentials. The way to find out if there's a ground loop problem is to hook it up and see.

The particular signal splitter (above) has two isolated outputs, each isolated from each other, the input and the power supply. So ground loops won't be a problem when using this splitter.

 

There are quite a few 4-20mA signal isolators available P+F, Redlion, even Automation Direct sell these. This would only be if you need an isolated signal as the previous poster stated 4-20mA is a loop and depending on your monitoring equipment you can usually install a few devices up to 750 ohms in some cases.