Conversion of BCD code to 4-20mA output

Hello hyo_eddie,

First of all: Here is a user forum, which is provided by Siemens. If you in the salutation "Siemens", Siemens will not answer you. Answers are only users from the forum, not Siemens.

The LOGO! has no blocks for converting decimal to BCD code or vice versa.
Since the user has to program the conversion itself.

But what should the BCD code be with 5 bits?
To represent a number as a BCD number, each decimal digit (0 to 9) is represented by four bits each (0000 to 1001), that is, in a nibble. The remaining six values (1010 to 1111) that can be represented by four bits do not represent valid BCD numbers and are also referred to as pseudotetracies.

Please give details, what you mean exactly.

hyo_eddie

Dear sir,

Actually BCD code is from my Transformer Tap position. I tabulated the equivalent BCD equivalent as per my transformer Tap position. Now my problem is my BCU can only accept 4-20mA signals. I want to use my LOGO! to convert the BCD signals in to 4-20mA signals so that my BCU can properly read it.

thanks.

What is a "Transformer Tap Position" ?

What is "my BCU"?

What is the input in LOGO!?

hyo_eddie

Actually BCD code is from my Transformer Tap position. I tabulated the equivalent BCD equivalent as per my transformer Tap position. Now my problem is my BCU can only accept 4-20mA signals. I want to use my LOGO! to convert the BCD signals in to 4-20mA signals so that my BCU can properly read it.

In your attached table is something with 5 bits, which looks like a BCD code.
Normally, a BCD code consists of 2 numbers of one byte, that is 8 bits.
So you are looking for 5 bits, how should we know this?

So, how cames the value in the LOGO! ?
As 5 digital inputs? Or as analog value?

My version does not only contain 4 bits, but 5 bits as required.

The analog value is output in 18 steps.