Analog scaling question

ixo65

Try this (see attachment).

 This produced the exact same result

Thanks for trying 

ixo65

No. Then make you not the same as I.

 I dont understand what you mean?

Also, just for kicks, I just measured the voltage with a good old DVM

6 PSI is reading 1.16 V

in 1-5V and 0 to 145 PSI that means each PSI should be about .027 Volts

6 * .027 +1 is very close to what i saw on the meter. So im very confident the instrument is working as it should.

RSCOTT117

[snip] 

in 1-5V and 0 to 145....[snip]

0 to 10V = 0 - 27648 units (Integer).
After converting Integer to Real over Norm_X, you have the values from 0.0 to 1.0.
0.1 equals 1V.
So I subtract 0.1V to correct the measurement range (offset).
As you already wrote, your usable range is 1V to 5V, giving you 4V.
For scaling, the corrected measuring range (0V to 4V) must be increased again to the value of the analog input. Therefore the multiplication by 2,5.
The scale block is then given as "Min" 0.0, with "Max" 145.0.
This converts the input signal from 1V to 5V to the value 0.0 to 145.0.

Yes thanks, i understand what your doing.

This works exactly the same as changing the norm only with a few more steps.

However, i am getting the same amount of error with your method as my method. 

the instrument reads about 15% different then that the PLC is getting.

ixo65

 

RSCOTT117

[snip] 

in 1-5V and 0 to 145....[snip]

0 to 10V = 0 - 27648 units (Integer).
After converting Integer to Real over Norm_X, you have the values from 0.0 to 1.0.
0.1 equals 1V.
So I subtract 0.1V to correct the measurement range (offset).
As you already wrote, your usable range is 1V to 5V, giving you 4V.
For scaling, the corrected measuring range (0V to 4V) must be increased again to the value of the analog input. Therefore the multiplication by 2,5.
The scale block is then given as "Min" 0.0, with "Max" 145.0.
This converts the input signal from 1V to 5V to the value 0.0 to 145.0.

ixo65

I can not understand your devotion, something is different with you.
I have set the voltage at the analog input so that the analog input after the conversion shows exactly 3222 units. The measured voltage at the analog input is 1.171 VDC (with a set measuring range of 2 VDC).
Attached is an online screenshot with the values and the complete calculation.

It is obvious you are confused.

YOUR METHOD produces the exact same result

You used 3222 as a test integer. Look at this screen shot

I used 3222 and got 6.00000 something

in your method you got 5.9999 

The methods are the same.

The problem is something else

RSCOTT117

It is obvious you are confused. 

If yo mean...