Input Parameter Module (1- In) Cn63300 Models; Input Type (Type); Decimal Point Position (Dcpt); Rounding Increment ( Rnd) - Omega CN63100 Series User Manual

Input Parameter Module (1- In) CN63300 models

The controller has several input set-up parameters that must be
programmed prior to setting any other controller parameters.

Input Type (tYPE)

Select the signal input type: Voltage (VOLt), or Current (Curr). The signal
input terminal for voltage is #9 and for current is #10. Common is #8.

Decimal Point Position (dCPt)

Select the desired decimal point position for the scaled display. The
selected decimal point position appears in the following parameters; rnd,
dSP1, dSP2, SPLO, SPHI, SP, AL1, AL2, db-2, AHYS, and CHYS.
0
0.0
0.00
0.000

Rounding Increment ( rnd)

Rounding values other than "1" causes the scaled number to 'round' to the
nearest rounding increment selected (i.e.. rounding of '5' causes '122' to
round to '120' and '123' to round to '125'). If the process is inherently jittery,
the display value may be rounded to a higher value than "1". If the range of the
process exceeds the required resolution, (ex. 0-1000 PSI, but only 10 PSI
resolution required), a rounding increment of 10 will effectively make the
display more stable.
This programming step is usually used in conjunction with programmable
digital filtering to help stabilize display readings. (If display stability appears
to be a problem and the sacrifice in display resolution is unacceptable,
program higher levels of digital filtering or increase the level of process
dampening.) Rounding increments of 10, 20, 50, and 100 may also be used to
add "dummy zeroes" to the scaled readings, as desired.
1
2
5
10
20
50
100
The rounding increment is for the controller's display only and does not
affect (improve or degrade) the control accuracy of the unit.

Digital Input Filtering and Display Update Rate (FLtr)

Select the relative degree of input signal filtering and display update rate.
The f ilter is an adaptive d igital f ilter that d iscriminates between
measurement noise and actual process changes. Therefore, the influence on
step response time is minimal. If the signal is varying too greatly due to
measurement noise, increase the filter value. Additionally, with large
derivative times, control action may be too unstable for accurate control.
Increase the filter value. Conversely, if the fastest controller response is
desired, decrease the filter value.
The Auto-tune procedure sets the filter value appropriate to the process
characteristics. See Output Power Dampening parameter (OPdP), page 35,
for filtering the output.
Fltr- 0 to 4
0 = least input filtering
3 = most input filtering
4 = most input filtering and slower (2/sec) display update rate
(outputs update at 10/sec rate)

Scaling Points

Prior to installing and operating the controller, it may be necessary to
change the scaling to suit the display units particular to the application.
Although the unit has been programmed at the factory, the scaling will
generally have to be changed.
The controller is unique in that two different scaling methods are available.
The two scaling procedures are similar in that the operator keys in the display
values and either keys in or applies a
signal value that corresponds to
those scaling points. The location of
the scaling points should be near the
process end limits, f or the b est
possible accuracy.
Once these v alues
programmed (coordinates o n a
graph), the indicator calculates the
slope and intercept
signal/display graph automatically.
No span/zero interaction occurs,
making scaling a one-pass exercise.
-32-
are
o f the
Figure 13, Scaling Points