1756-IF8 Wiring

[Kilowatt76]

Hi,

I'm new here and very much a beginner. I had a question about this AB 1756-IF8 Analog card and how to correctly wire it. I looked in the manual and I was trying to figure out this card. The panel is being supplied with 120V AC and I using 120V AC Input/Output modules as well. Does the the 1756-IF8 require a separate 24V DC power supply to the card? I'm use to using the 1769-IF4 where you supply (+) and (-) 24V to terminals on the card. I will be connecting a 4-20 mA signal from a flow meter transmitter. I appreciate any help with this!
Is there anyone that can show a cad drawing on how this should be properly wired?

Thanks,
Kilowatt76

 

[mylespetro]

Do you know if the flow transmitter is a two-wire or four-wire transmitter? In other words, does the flow meter have a separate (typically 120VAC) power feed to it and then a separate pair of wires for the 4-20mA signal? Or is it powered by a 24VDC supply and then the 4-20mA signal is on the same loop (loop-powered transmitter)?

 

[mylespetro]

I've attached a good reference photo of some typical analog input wiring setups (I think you can safely disregard the 3-wire transmitter example). The terminals on an IF8 are a little more complex so I'll see if I can mark up an example from the manual.

 

[Kilowatt76]

The flow meter has a 120V AC power feed and a separate pair of wires for the 4-20mA signal.

 

[Kilowatt76]

Thanks and I appreciate you doing that!

 

[mylespetro]

I've attached a quick MS Paint sketch, note that this is for single-ended wiring (non-differential), someone may chime in and say that it needs to be differential, in which case you can just refer to the equivalent diagram in the manual and move the negative wire as required. The diagram on the left is as it is in the manual, and on the right is the wiring for your application.

 

[danw]

Many AC powered flow meters provide either a passive “2-wire” loop powered 4-20mA output that requires an external 24V dc power supply wired in the “loop”, or an active “4-wire” 4-20mA output powered by the flowmeter.

If you put the probes of a multi meter, set to read 20mA DC max on the milliamp meter scale) and you get any value between 4 or 20 mA, then the output is an “active” 4-wire output, powered by the flow meter.

If there is no mA reading, then the output is 2-wire and needs an external power supply to generate a mA signal.

That I/O card can be powered by rack DC power (by default), or powered by an external 24Vdc power supply (those terminals you mention) but powering the module is a separate issue from how the 4-20mA signal is powered.

 

[Kilowatt76]

 

[Kilowatt76]

I was trying to add an image but I couldn't figure it out?

 

[Kilowatt76]

Thank you for all of that information and I found a manual for the Hach FL1500 Flow Logger. It look likes this can be wired both ways, The FL1500 can power the loop or an external source to power it. I will be supplying it externally and I was going trying to insert some pages of the manual to show you as an example.

 

[Kilowatt76]

https://support.hach.com/app/answer...l-user-manual:-fl1500-stationary-flow-logger-

 

[Kilowatt76]

https://cdn.brandfolder.io/7FYZVWYB...r_Manual_FL1500_Flow_Logger_DOC3435380573.pdf

 

[Kilowatt76]

I attached a link to the PDF manual, it shows the wiring starting on page 23 - 24.
Please let me know when you can and let me know what you think

Thanks again!

 

[Kilowatt76]

Do I only need the jumper from iRTN-0 to RTN for IN-1, IN-2 and IN-3? I just want to make sure I;m showing this on my drawing correctly. I will be using all 8 points on this card.

Thanks and Happy Friday!!!!

 

[Chris_M]

Based on the image that mylespetro posted you should need a RTN jumper to all points that you are using.

The image shows that i RTN 0 and i RTN 5 are both wired to the RTN