RTD to PLC

hi guys,

im kind of new to PLC programming, there's a project i need to complete and it's related to heating.

i did the PLC program in TIA V13 and the wiring for the TT.
The problem i'm facing is that the TT isn't sending any signal to my Analog input ( AI 8 x 13 bit )
The TT with transmitter is calibrated with no problems.
The wiring are based on manuals I've download from the internet. (two wire)

i've attach a picture of scale which is one of the block to read the signal of RTD and IW298 is suppose to be from the TT.
" http://imgur.com/j60XFkk "

as you can see the signal from IW298 is "0".

Just wondering who can help me because I've been dealing with this problem for 2 days with no progress at all.
any help would be great.
and again, i new to this and did not have any proper PLC lesson. if would be great if you experts can help.
i will send my full program for the scale,con_c and unscale if requested.

Are you powering the current loop with 24VDC??? or is the PLC analog input configured for active?
What is the ref. of the analog input card etc.

nonuke said:

Are you powering the current loop with 24VDC??? or is the PLC analog input configured for active?
What is the ref. of the analog input card etc.

Click to expand...

Yes I am powering the current loop with 24VDC.
and I am not quite understand what you mean by PLC AI configured for active.

ref. for AI 8x 13 Bit ( 331-1KF02-0AB0 )

not idea on TIA,

are the RTD output 4-20 mA ,VOLT or something else.

The problem could be in the way you've wired the transmitter to the analog input channel or in the way you've configured the channel.

First try to measure the signal with your multimeter. If there is no signal, the value of zero in %IW298 could be correct.

Are you sure that the address %IW298 is associated with the analog channel you've wired the transmitter to? Are you sure the analog channel is configured for 4 -20 mA And not voltage?

"I am not quite understand what you mean by PLC AI configured for active."

You should read the manual of the analog card.

In what position is the switch on the side of the analog card (ABCE) for the input?
If passive, it must be "C"

Steve Bailey said:

The problem could be in the way you've wired the transmitter to the analog input channel or in the way you've configured the channel.

First try to measure the signal with your multimeter. If there is no signal, the value of zero in %IW298 could be correct.

Are you sure that the address %IW298 is associated with the analog channel you've wired the transmitter to? Are you sure the analog channel is configured for 4 -20 mA And not voltage?

Click to expand...

i am so sure that the TT can gives 4 - 20mA. But when i connect it in Analog Input Module, the program show 0 value for %IW298.
Even when i replace TT to multi function calibrator and inject 4 - 20mA into AI module. it's still value 0 in the program.

%IW298 is associated with the right analog channel.
The analog channel is already configured for 4 - 20mA.

now, i suspect the analog input has broken. but don't really know whether its really broken or not.

Edit - Even when i changed to another analog input module like 8 x 13 Bit, the value is still 0.
so its not the analog input module's fault? i am so confused really.

nonuke said:

"I am not quite understand what you mean by PLC AI configured for active."

You should read the manual of the analog card.

In what position is the switch on the side of the analog card (ABCE) for the input?
If passive, it must be "C"

Click to expand...

i followed the steps from the module's manual and uses D from the (ABCD) for two wire connection.
if i'm wrong please correct me.

osmanmom said:

not idea on TIA,

are the RTD output 4-20 mA ,VOLT or something else.

Click to expand...

i had checked with multimeter for my TT and the output is 4 - 20mA

what analog input card are you using?

dwoodlock said:

what analog input card are you using?

Click to expand...

Analog input module SM 331; AI 8 X 13 BIT; (6ES7331-1KF02-0AB0)
Just changed it to this analog input module and the result are still the same. 0 value.

I cant say for sure, just make sure your wiring is correct.

I have only used TIA with 1200 series components, so I'm not much use for the older hardware.

dwoodlock said:

I cant say for sure, just make sure your wiring is correct.

I have only used TIA with 1200 series components, so I'm not much use for the older hardware.

Click to expand...

i am currently using AI 8x 13 Bit ( 331-1KF02-0AB0 )
so my wiring should look like this.

You have a 4-20mA sensor and you wired it up like it is a RTD sensor.


edit: you changed your schematics. This is better. So, do you have a passive or active transmitter? And how did you connect it, 2-wire or 4 wire?

I am also a little confused as to what kind of sensor you are using.