Beckhoff EL3182, Документация

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Commissioning
EL3182 104 Version: 1.2
Fig. 105: Measurement range representation 3.6…21mA (NAMUR)
5.4.5.2 Undershoot and overshoot of the measuring range (under-range, over-
range), index 0x60n0:01, 0x60n0:02
Under-range/ over-range, index 0x60n0:01/ 0x60n0:02
Chapter Data stream and correction calculation contains a clear description of the correction calculation
between the raw values and the output values if the limit ranges are exceeded.
5.4.5.3 Limit 1 and limit 2, index 0x80n0:13, 0x80n0:14
If the value exceeds or falls below these values, which can be entered in the indices 0x80n0:13 and
0x80n0:14, then the bits in the indices 0x60n0:03 and 0x60n0:05 are set accordingly (see example below).
The indices 0x80n0:07 or 0x80n0:08 serve to activate the limit value monitoring.
Output limit n (2-bit):
• 0: not active
• 1: Value is smaller than the limit value
• 2: Value is larger than the limit value
• 3: Value is equal to the limit value
Limit evaluation
The limit evaluation assumes a signed representation. The conversion to the desired representation
(index 0x80n0:02) only takes place after the limit evaluation.
Note on linking in the PLC with 2-bit values
Linking in the PLC with 2-bit values
The limit information consists of 2 bits. Limitn can be linked to the PLC or a task in the System Man-
ager.
• PLC:
IEC61131-PLC contains no 2-bit data type that can be linked with this process data directly. For
transferring the limit information, define an input byte (e.g. see Fig.
Input byte definition) and link the
limit to the VariableSizeMismatch dialog, as described in section Note about the 1-byte status of earlier
EtherCAT Terminals.