Basic Operation; Default State; Process Data; 4/2-Wire Mode - Beckhoff EL3692 Documentation

• CoE mode (default setting)
The settings for Autorange activation, Range (measuring range) and Mode (2/4-wire measurement) are
made via the CoE objects. During commissioning they are accessible online via the TwinCAT System
Manager. During system runtime these objects can be addressed through ADS via acyclic EtherCAT
telegrams.
• Control Word
When the 16-bit control word is activated in the PDO settings, the EL3692 will only respond to
instructions from the control word: Disable Autorange, Start conversion (SingleShot mode), Range and
Mode. The respective CoE entries are then ignored.
5.5.2

Basic operation

We recommend operating the EL3692 as follows. Other operating modes referred to in this documentation
are, of course, also permitted.
1. CoE mode
2. Autorange enabled

3. Process data

- Utilization/linking of the measuring range-independent fixpoint-float process variable value
- Monitoring of WcState (=0) and State (=8) in each cycle
- Monitoring of TxPDO state (=0) and TxPDO toggle (toggling)
- Status.Error = 0
- Status.DataInvalid = 0
4. The value can be used when Status.steadyState = 1
5.5.3

Default state

• Process image with range-dependent and range-independent value
• 4-wire mode
• CoE mode
• AutoRange active
5.5.4 Process data
See page Process data. [} 111]
5.5.5

4/2-wire mode

For measuring a resistance via the 9 available measuring ranges on 2 channels in 2- and 4-wire mode the
EL3692 has 9*2*2 = 36 manufacturer calibration data, consisting of gain and offset. Accordingly, 36 user
calibration entries are available for user gain and user offset.
Calibration in 2-wire mode
For the lower 3 measuring ranges (10mΩ - 10 Ω) 2-wire mode only makes sense if the con-
nection characteristics (line lengths, contact resistances) are known exactly. In these 3
Note
measuring ranges the EL3692 is therefore not calibrated by the manufacturer for 2-wire
measurement mode.
In Autorange mode with 2-wire connection these 3 measuring ranges are therefore not
used.
The 3 measuring ranges can be used through manual settings (CoE or control word). Previ-
ous user calibration by the customer is essential.
EL3692 Version: 2.1
Commissioning
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