Averaging; Peak And Valley Hold; Peak/Valley Truth Table - Siemens SIMATIC 505 Installation And Operation Manual

Additional Information about Each Function (continued)

Averaging

Peak and Valley
Hold
3-22 Advanced Function Programming
Exclusivity If averaging and filtering are both enabled, alarming is
exclusive of averaging. This means that after the data is filtered it is
compared against alarm setpoints and then averaged.
Numerical Range Values loaded into the module for averaging are
expressed as 16-bit unsigned integers 1 to 65535 in units of number of
samples. Signed integers will be interpreted as unsigned values.
NOTE: A value of zero is ignored and the default value of 20 is used if zero is
loaded and enabled.
Averaging Reset Y27 is used to reset all 16 channels to begin the
averaging process again. The previously loaded averaging sample number is
used (or the default value of 20 if no data is loaded) and the averaging
function is enabled.
Averaging Reset with New Value In the event a very large number for
averaging is inadvertently loaded into the module and enabled, the input
channel will appear to not be working correctly. The input channel requires
a reset with a smaller number of samples. To initate a reset with a new
averaging value, the number of samples is loaded as previously described
and then each channel may be individually reset and enabled for the new
value with WY75.
Peak or valley hold data is returned in locations WX49 – WX64, provided
that Y30 and Y31 are set accordingly. See Figure 3-14.
Figure 3-14 Peak/Valley Truth Table
NOTE: Upon power up and the enabling of peak and valley hold, peak
values returned will be the actual value at input. Valley values must go
below zero, which is the default value before data is returned. This is not
the case if a reset is issued to the valley function. On reset the valley
threshold is the current value.
Data Read Y30
Peak 1
Valley 0
Flags X
SIMATIC 505–2556 Installation and Operation Guide
Y31
1
1
0