Different types og ranges

Hi guys!
1 week until examination and i was woundering if someone here could give me an explanation on what the difference between Rated range, over range, under range, overflow and underflow are?

thx

Tell us what you think they mean. Also explain what devices or systems your examination is applying those terms to.

SIMATIC S7 module, I think underflow and overflow has something to do whith high signal jumps that the settling curve of the signal briefly leaves the rated range until it reaches the setpoint and dont shows as en error. But i can`t see the difference between Underflow and underrange as well as overflow and overrange.

Example:
0-10V rated range
10V-11.759V overrange
11.759-11.852 overflow

0-27648 rated range
27649-32511 overrange
32512-32767 (=2^15-1) overflow

Overflow and underflow will cause an error. Overrange and underrange can happen during high signal jumps while the curve is settling.

Thanks! This was helpfull. I have another question, what is the main difference between the L-stack and the B-stack? Stupid question probably, but I have no idea, and this examination is starting to wear me down...

When a block gets interrupted by error handling for example the systems saves the number and type of block interrupted and the return address of the block that was interrupted and the numbers of the datablock and Di registers open.

This is saved in the B stack (block stack).

Basically if you have your pc connected to the plc when it goes into stop mode, you have use this information to find out why.

L-stack is the local data, I think it's just where all the temporary variables are stored.


Edit: sorry not sure on the above info.

Thanks again I read somewhere on the word wide web, that: Function (FC), Function Block (FB) and Data Block (DB) are blocks saved in the B-stack. In the L-stack things like Arguments to mathematical functions, Intermediate results of logic operations, Data packets for communication tasks and tags that are connected to GUI (Graphical User Interface) are stored. Does this sound correct? or have i been trolled by the WWW?

Check page 3:
http://www.infoplc.net/files/descargas/siemens/infoplc_net_sitrain_11e_fc_fb.pdf