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General => Technical support => Topic started by: Bill Alexander on June 14, 2006, 09:33:29 AM

Title: Analog on PLC
Post by: Bill Alexander on June 14, 2006, 09:33:29 AM

I am starting a project on which I would need an analog input and analog output.  Is there any way to do that with a T100MX-3224R+?  If so, what voltage range can I utilize?

Title: Re:Analog on PLC
Post by: support on June 14, 2006, 06:11:28 PM

All the T100MD+ and T100MX+ PLCs have analog inputs and outputs. Most of them are 0-5V. The T100MX-3224R+ PLC has 6 analog inputs 0-5V and 2 analog outputs which are also 0-5V.

T100MD1616+ PLC has 2 channels of analog inputs that are 0-1V range and its single analog output is 0-20mA current loop which can be converted to 0-5V or 0-10V. It also has 2 channels of 0-5V analog inputs.

Title: Re:Analog on PLC
Post by: FQ-ONG on June 19, 2006, 02:53:05 AM

Do any PLC analog inputs or analog output is 4-20mA?
How to connect a 4-20mA analog to the T100MD+ PLC analog inputs? (6 analog inputs 0-5V)

Thank you.

Title: Re:Analog on PLC
Post by: support on June 19, 2006, 09:14:36 AM

4-20mA signal connects to a 250 ohm resistor will become 1-5V which can be connected to the PLC 0-5V analog input.

Only T100MD1616+ has 1 channel of 0-20mA output which can be scaled to 4-20mA using some math statement. All other PLCs have only 0-5V which will need external converter if you want to convert to 4-20mA.

Title: Re:Analog on PLC
Post by: FQ-ONG on June 20, 2006, 01:16:27 AM

If 4-20mA signal connects to a 250 ohm resistor will become 1-5V which can be connected to the PLC 0-5V analog input. Then, how to scale the 1-5V into the 0-5V (0 to 4092)? What are the formula to convert 0 to 4092 into the value of 4-20mA signal? Do it appropinquity with original value?

Thank you.

Title: Re:Analog on PLC
Post by: support on June 20, 2006, 10:17:42 AM

1V = ADC reading of 820
5V = ADC reading of 4096 (full scale-maximum reachable is 4092).

Your typical purpose is not to scale 1-5V to 0-5V, but to scale the analog input into some meaningful data such as temperature or pressure etc. For details on scaling, see the following thread:

http://www.tri-plc.com/yabbse/index.php?board=2;action=display;threadid=349

Title: Re:Analog on PLC
Post by: Bill Alexander on June 23, 2006, 08:06:58 AM

Thanks for the quick response to my last question.

Is there any way to simulate Analog I/O, without doing a bench test?
I have Trilogi 5.3(3)

Thanks!

Title: Re:Analog on PLC
Post by: support on June 23, 2006, 09:03:48 AM

If you run the simulator, you can enter the analog reading via the Simulator windows. Enter a value between 0 and 4092 only so that your program can operate based on the entered data.