X20 system modules • Temperature modules • X20AT4222
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X20 system User's Manual 3.10
4.31.4.8.3 Analog inputs
This module stores converted analog values in the registers. Different resistance or temperature measurements
will result in different value ranges and data types.
Information:
Operating channels outside the specification can have an effect on neighboring channels.
4.31.4.8.4 Analog input values
Name:
Temperature01 to Temperature04
Resistor01 to Resistor04
The analog input values are mapped to this register depending on the configured operating mode.
Data type
Digital value
Input signal
-2000 to +8500 (for -200.0°C to +850.0°C)
Sensor type PT100
INT
-2000 to +8500 (for -200.0°C to +850.0°C)
Sensor type PT1000
1 to 45000 (resolution 0.1 Ω)
Resistance measurement 0.1 Ω to 4500 Ω
UINT
1 to 45000 (resolution 0.05 Ω)
Resistance measurement 0.05 Ω to 2250 Ω
In order for the user to always be supplied with a defined output value, the following must be taken into consid-
eration:
•
Up to the first conversion, 0x8000 is output.
•
After switching the sensor type, 0x8000 is output until the first conversion.
•
If the input is not switched on, 0x8000 is output.
4.31.4.8.5 Timing
The timing for acquiring measurement values is determined by the converter hardware. All switched-on inputs are
converted during each conversion cycle and transferred halfway through the X2X Link cycle.
4.31.4.8.6 Conversion time
The conversion time for the channels depends on their use. For the formulas listed in the table, "n" corresponds
to the number of channels that are switched on.
Channel uses
Conversion time
1 channel
1
⋅
Filter time
n channels with the same sensor type
n
⋅
(20 ms + Filter time)
n channels with different sensor types
n
⋅
(20 ms + 2
⋅
Filter time)
4.31.4.8.7 Reduced update time
Any inputs that are not needed can be switched off, which reduces the I/O update time. Inputs can also be only
switched off temporarily.
Calculating the time saved
The amount of time saved can be calculated with the following formula. And "n" corresponds to the number of
inputs that are switched off.
Time saved = n
⋅
(20 ms + filter time)
Examples
Inputs are filtered using a 60 Hz filter.
Example 1
Example 2
Example 3
Switched on inputs
1
1, 3
1 - 4
Conversion time
16.7 ms
73.4 ms
146.8 ms
Summary of Contents for X20 System
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