String Parsing Issue

[PLCwannabe]

See attached. I'm trying to retrieve "currentValue" from string SL0.  The instruction completes every time, but always returns value 3.0, rather than the expected value 7.0  . What could be the problem here? All the registers are only being used in that rung, I've tried using different registers, still getting the same results. If I use a string as the result, everything works correctly.

[franji1]

You don't utilize the Return Result of your JSONPARSE.  It is probably failing because the value is NOT numeric, but is a STRING containing the text of a numeric value (that string could be "ABC", not "123").

The difference is the key/value pair of
"currentValue":"7.0"
"currentValue":7.0
(notice the difference?)

You will need to put the value of JSONPARSE key into another STRING element (e.g. SS0), then use a STR2REAL instruction to convert SS0 to KETherm25.

[BobO]

See attached. I'm trying to retrieve "currentValue" from string SL0.  The instruction completes every time, but always returns value 3.0, rather than the expected value 7.0  . What could be the problem here? All the registers are only being used in that rung, I've tried using different registers, still getting the same results. If I use a string as the result, everything works correctly.

The value type is a string. When you assign a string to numeric, it just stuffs the length rather than attempting any form of conversion. I probably wouldn't have returned a float value as a string, particularly since they already had a string description, but that's what they've done.

[PLCwannabe]

Right on. Thanks guys.