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Time Using 4-20mA/1734-IE4C Module

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PDAView Full Version : First Time Using 4-20mA/1734-IE4C Module

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jfd7851November 2nd, 2016, 11:13 AM

Hi everyone,

As stated in the title, this is my first time configuring a 4-20mA device and I am using Rockwell's 1734-
IE4C module as part of the Point I/O module. The sensor I am connecting has three wire leads. One is
red which I am assuming is +, One is black which I am assuming is - and one is green which I'm assuming
is ground.

Based off the amount of wires and the picture from the IE4C manual, it seems like I would connect the
red + into one of the input channels, black into the common, and the green into the Chassis Ground
terminal?

If anyone has any experience wiring 4-20mA and could offer some words of wisdom, I would greatly
appreciate it. Thank you.

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JeremyMNovember 2nd, 2016, 11:34 AM

Do you have a diagram of the sensor?

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jfd7851November 2nd, 2016, 11:40 AM

This was the best one I could find.

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jfd7851November 2nd, 2016, 11:42 AM

This is the sensor:

http://www.te.com/usa-en/product-CAT-PTT0051.html#mdp-tabs-content

The manual I am using is the one linked in the page

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JeremyMNovember 2nd, 2016, 11:55 AM

Apply 24VDC to the red wire. The black wire carries the sensor signal to the 1734 input point.

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jfd7851November 2nd, 2016, 11:59 AM

Thanks. Doesn't the Point IO supply the 24VDC? Right now, I've got the red wire into the Channel 0 "IN"
terminal, the black signal wire into the Common (Input 4), and the Ground going into the Chassis Ground
(Input 6)

EDIT: I see where I am making a mistake. Channel 1 is for the 24VDC wire(red). Channel 0 is for the black
signal wire, and the ground wire goes to chassis ground terminal

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JeremyMNovember 2nd, 2016, 12:03 PM

The IE4C module does not provide a 24VDC contact on the AENT bus. You can source it from a neighbor
module, though.

IE4C contacts are as follows:

0-3: Inputs
4-5: DC common

6-7: Chassis ground

In your present setup, the sensor is not being energized.

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jfd7851November 2nd, 2016, 02:15 PM

Ahhh. Ok. i'm seeing it better now.

+ (red wire) to voltage source (VTM)

- (black wire) to corresponding input (1 in my case)

G (green wire) to ground (terminal 6 in my case)

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jfd7851November 2nd, 2016, 06:00 PM

I can't seem to get the channel to recognize the connection (Channel 1- still flashing red on the 1734-
IE4C module. I did some manual measurements with a multimeter and the values seem to be correct.
Anyone have any issues in the past getting the IE4C to recognize a connection?

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jkerekesNovember 2nd, 2016, 06:46 PM

Did you set the chassis size?

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JeremyMNovember 2nd, 2016, 06:48 PM

Start by verifying the sensor is supplying a value to the module. See if this measured value is within the
module's alarm range settings.

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Paully's5.0November 2nd, 2016, 06:53 PM

FYI, when it comes to Point IO or any other "slice" IO type I try to go with the 2 point variants for the
specific purpose of field wire termination. The 1734-IE2C has a voltage terminal, so ideal if you have 2
wire analog transmitters. If I had nothing but 4 wire transmitters, then the 1734-IE4C would be fine,
however I stick with the 2 channel to provide better flexibility.

I don't really like higher density cards, whats the point if I just have to terminate wires elsewhere in the
panel or add voltage/common cards?

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jfd7851November 2nd, 2016, 08:21 PM

I checked the chassis size for the 1734-Aentr and it matches up right (mistake I made in the past that I
won't be forgetting anytime soon). The data channel is showing a -5, that sometimes oscillates to -6, but
when I tried to create some pressure to get above 4mA I noticed there was no change. I remember with
the 1734-IF4U module I had to specify which channels were used and which aren't. I haven't found any
option like that in the module properties for IE4C.

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robertmeeNovember 2nd, 2016, 08:47 PM

What version of an IE4C are you using? I just did a crapload of them, ver C, and you have to set the
scaling on the module configuration tab. The default is 16383 to 3277, so if you're reading -5, then that's
pretty much 0ma, which means you have it wired wrong.

First thing, go online and check that you have no yellow triangle by the 1734-IE4C in your I/O tree. If it's
good, then double click on it, go to the module info tab...Should report the version, and Match, meaning
it's configured correctly and seen by the processor correctly. If it times out, then you aren't reading the
module (and probably have the yellow triangle). If that's good, go to the configuration tab, and enter the
scaling you want and select 4-20ma.

If you still aren't reading anything, put your meter on mA, and put it in series in between your black wire
and the input terminal on the module. Red meter lead on black wire, black meter lead on module. See if
you're reading anything above 4ma. If not, then sensor not working or not wired correctly. Not sure
from your diagram why you are tieing the green wire to ground...leave it unhooked from what I see.
Two wire sensors don't usually have a ground...just a shield on the cable.

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danwNovember 2nd, 2016, 09:21 PM

I know nothing about the PLC side, but I'm confused as to why you think the transmitter wiring is
correct. There's a wiring manual with dozens of wiring diagrams,

http://www.te.com/commerce/DocumentDelivery/DDEController?Action=srchrtrv&DocNm=TESS_Instal
lation-Wiring_AST&DocType=SS&DocLang=EN

but it is arranged by connection style, and does not refer to model numbers. In any event, I can't find a a
3 wire red/black/green combination.

The 3 wire voltage flying lead model uses Black/red/white wires

https://s15.postimg.org/k4s3kum5n/AST_Wiring_diagrams.jpg

From where do you determine your wiring connectionsfrom?

http://www.plctalk.net/qanda/I know nothing about the PLC side, but I'm confused as to why you think
the transmitter wiring is correct.There's a wiring manual with dozens of wiring diagrams, but it is
arranged by connection style, and does not refer to model numbers.In any event, I can't find a a 3 wire
red/black/green combination. The 3 wire voltage flying lead model uses Black/red/white wires

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jfd7851November 3rd, 2016, 08:20 AM

This is the wiring specification for the sensor I am using.

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AustralIanNovember 3rd, 2016, 10:40 AM

Ahhh. Ok. i'm seeing it better now.

+ (red wire) to voltage source (VTM)

- (black wire) to corresponding input (1 in my case)

G (green wire) to ground (terminal 6 in my case)

You need to connect the common pin (terminal 4 or 5) of the 1734-IE4C to the 0V of your 24V DC power
supply. This gives the current a path to follow.

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JeremyMNovember 3rd, 2016, 10:47 AM

AustralIan:

If the AENT adapter is already powered, he doesn't need to wire the module to DC common since the
Point rack has a backplane bus handling the common. IE4C module just doesn't provide a +24V contact.
Check out pages 14-15:

http://literature.rockwellautomation.com/idc/groups/literature/documents/in/1734-in032_-en-p.pdf

You can verify this by using a multimeter to measure the potential from the power supply's DC+ to
points 4 or 5 on the module's terminal block: 24VDC.

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JeremyMNovember 3rd, 2016, 10:56 AM

This is the wiring specification for the sensor I am using.

Row 2 is exactly your answer since you are measuring a 4-20mA signal: energize the sensor (+24V) with
the red wire, terminate the black wire to your desired input channel.

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jfd7851November 3rd, 2016, 12:18 PM

Row 2 is exactly your answer since you are measuring a 4-20mA signal: energize the sensor (+24V) with
the red wire, terminate the black wire to your desired input channel.

I've had it wired that way, but I still can't seem to get the Module to recognize the channel in use(still
flashing red). Using a multimeter I can see that the 1734-VTM card is providing the voltage through the
red wire. I've got the black wire wired into Input Channel 1. I tried scaling the engineering units,but it
doesn't seem to help.

Also, thanks everyone for your help so far. This forum is awesome.
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jfd7851November 3rd, 2016, 02:12 PM

Happy to report I found the problem, and it's a bit goofy so feel free to laugh at me....The wire leads on
the sensor were wired in too far to the terminal so there was never any metal on metal contact. Re-
wired with less tension and pulled back out of the module some and am good to go.

Thanks again to everyone who replied

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