gefran GFX4 Configuration And Programming Manual page 13

Read state
0
P.V.
470
85
Err
For custom linearization (tYP = 28 or 29):
- LO is signaled with input values below Lo.S or at minimum
calibration value.
- HI is signaled with input values above Lo.S or at maximum
calibration value.
ADVANCED SETTINGS
Input filters
24
flt
Sets a low pass digital filter on the main input, running the average value read in the speci-
fied time interval. If = 0 exclude the average filter on the sampled values.
179
fld
Introduces a hysteresis zone on the input signal value within which the signal is considered
unchanged, thereby increasing its apparent stability.
Linearization of input signal
The modular power controller lets you set a custom linearization of the signal acquired by the main input for signals coming
from sensors and for signals coming from custom thermocouples.
Linearization is performed with 33 values (S00 ... S32: 32 segments).
S33, S34, S35 are an additional 3 values to be inserted in case of linearization with custom CT.
- Signals from sensors
For signals coming from sensors, linearization is done by dividing the input scale into 32 zones of equal dV amplitude, where:
Point 0 (origin) corresponds to the engineering value attributed to the minimum value of the input signal.
Subsequent points correspond to the engineering values attributed to input values equal to:
where k is the order number of the linearization point
S.32
S.24
...
S.12
...
S.05
...
S.00
80397M_MSW_GFX4-GFXTERMO4_08-2018_ENG
Read of engineering value of
R
process variable (PV)
Self-diagnostic error code
R
of main input
Low pass digital filter
R/W
on input signal
Digital filter on oscillations
R/W
of input signal
dV = (full-scale value – start of scale value) / 32
Input value (k) = Minimum input value + k * dV
Example of linearization:
0 9.375mV = 5 * (f.s./32)
0 No Error
1 Lo (process variable value is < Lo.S)
2 Hi (process variable value is > di Hi.S)
3 ERR [third wire interrupted for PT100 or input values below minimum
limits (ex.: for CT with connection error)]
4 SBR (probe interrupted or input values beyond maximum limits)
0.0 .... 20.0 sec
0 ... 9.9
scale points
22.5 mV
Error code table
Ex.: Input 0...60mV
45 mV f.s. = 60 mV
0,1
0,5
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