Beckhoff KL3102, Documentation

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Product Overview
KL3102, KL3112, KL3122 14 Version: 3.2
2.6 Basic function principles
The analog input terminals process signals in the range of:
KL3102: -10 V ... +10 V
KL3112: 0 mA ... 20 mA
KL3122: 4 mA ... 20 mA
with a resolution of up to 16 bits (65535 steps). The terminal inputs are differential inputs with common
ground. Due to the differential inputs, the terminals are particularly suitable for floating measuring of voltage
drops. In the standard version, a filter with a stop frequency (64.5 dB) of 50 Hz is active. The filter constant
and the associated conversion time are configurable in a wide range.
The green Run LEDs indicate the operating state of the associated terminal channel.
• On: Normal operation
• Off: Watchdog-timer overflow has occurred. If no process data are transmitted by the Bus Coupler for
100 ms, the green LEDs go out.
The red ERROR LEDs indicate an overflow.
• On: Measured current outside the measuring range (> 20 mA)
• Off: Current in valid range
KL3102 - Output format of the process data
In the delivery state the process data are shown in two's complement form (integer -1 corresponds to
0xFFFF). Other presentation types can be selected via the feature register (
R32) [ } 38] (e.g. signed amount
representation, Siemens output format).
Measured value Output
KL3102 dec hex
-10 V -32768 0x8000
-5 V -16383 0xC001
0 V 0 0x0000
5 V 16383 0x3FFF
10 V 32767 0x7FFF
KL3112, KL3122 - Output format of the process data
In the delivery state the process data are shown in two's complement form (integer -1 corresponds to
0xFFFF). Other presentation types can be selected via the feature register (
R32 [
}
38] ) (e.g. signed amount
representation, Siemens output format).
Measured value Output
KL3112 KL3122 dec hex
0 mA 4 mA 0 0x0000
10 mA 12 mA 16383 0x3FFF
20 mA 20 mA 32767 0x7FFF
Calculation of process data
The terminal continuously records measured values and stores the raw values of its A/D converter in register
R0 [
}
36] (RAM ). The calculation of the correction with the calibration values takes place after each
sampling of the analog signal. This is followed by manufacturer and user scaling:
The process data that are transferred to the Bus Coupler are calculated using the following equations: