UMAX130511 Version 1.00A Preliminary Documentation
– May be subject to change
19 - 141
Table 7
– Object 61A0h - AI Filter Type Options
Object 61A1h
AI Filter Constant
is used with all three types of filters as per the formulas below:
Calculation with no filter:
Value = Input
The data is simply a ‘snapshot’ of the latest value measured by the ADC or timer.
Equation 1 - Moving Average Transfer Function:
Value
N
=
Value
N-1
+
(
Input-
Value
N-1
)
Filter Constant
This filter is called every 1ms. The value Filter Constant stored in object 61A1h is 10 by default.
Equation 2 - Repeating Average Transfer Function:
Value=
∑
Input
N
N
0
N
At every reading of the input value, it is added to the sum. At every N
th
read, the sum is divided by
N, and the result is the new input value. The value and counter will be set to zero for the next read.
The value of N is stored in object 61A1h and is 1 by default. This filter is called every 10ms.
The value from the filter is shifted according to read-only object 2102h
AI Decimal Digits FV
and
then written to read-only object 7100h
AI Input Field Value.
The value of 2102h will depend on the
AI Sensor Type
and
Pulses per Revolution
selected and
will be automatically updated per Table 9 when either 6110h or 2101h are changed. All other
objects associated with the input field value also apply this object. These objects are 7120h
AI
Scaling 1 FV
, 7122h
AI Scaling 2 FV
, 7148h AI
Span Start
, 7149h
AI Span End
, and 2111h
AI
Error Clear Hysteresis
. These objects are also automatically updated when the Type or Pulses
per Rev are changed.
Sensor Type
Decimal Digits
Voltage: All Ranges
3 [mV]
Current: 0-20mA and 4-20mA
3 [uA]
Current: 0-200mA
2 [10 uA]
Frequency: 0.5Hz to 50Hz
2 [0.01 Hz]
Frequency: 10Hz to 1kHz
1 [0.1 Hz]
Frequency: 100Hz to 10kHz
0 [Hz]
Frequency: RPM Mode
1 [0.1 RPM]
Resistive
0 [0.01 k
Ω]
PWM: All Ranges
1 [0.1 %]
Digital Input
0 [On/Off]
Table 8
– Object 2102h AI Decimal Digits FV Depending on Sensor Type
