Beckhoff EP3356-0022 Documentation page 81

8. Zero balance: Do not load the scales. As soon as the measured value indicates a constant value for at
least 10 seconds, execute the command "0x0101" (257dec) on CoE object 0xFB00:01 [} 102]. This
command causes the current mV/V value (0x9000:11 [} 104]) to be entered in the "Zero balance" ob-
ject. Check: CoE objects 0xFB00:02 [} 102] and 0xFB00:03 [} 102] must contain "0" after execution
9. Load the scales with a reference load. This should be at least 20 % of the rated load. The larger the
reference load, the better the sensor values can be calculated. In object 0x8000:28 [} 104] ("Reference
load"), enter the load in the same unit as the rated load (0x8000:24 [} 104]). As soon as the measured
value indicates a constant value for at least 10 seconds, execute the command "0x0102" (258dec) on
CoE object 0xFB00:01 [} 102]. By means of this command the EL/EP3356 determines the output value
for the nominal weight ("Rated output") Check: CoE objects 0xFB00:02 [} 102] and 0xFB00:03 [} 102]
must contain "0" after execution.
10. Reset: execute the command "0x0000" (0dec) on CoE object 0xFB00:01 [} 102].
11. Set the filter to a lower stage.
Calibration according to the sensor calibration protocol (theoretical calibration)
The sensor characteristic values according to the manufacturer's certificate are communicated here directly
to the EL/EP3356, so that it can calculate the load.
1. Perform a CoE reset with object 0x1011:01, see Restoring the delivery state [} 118]
2. Set scale factor to 1000 (0x8000:27 [} 104]) (for declaration of weight in g)
3. Set gravity of earth (0x8000:26 [} 104]) if necessary (default: 9.806650)
4. Set gain to (0x8000:21 [} 104]) = 1
5. Set tare to 0 (0x8000:22 [} 104])
6. Specify the nominal load of the sensor in 0x8000:24 [} 104] ("Nominal load")
7. Adopt the "Rated output" (mV/V value 0x8000:23 [} 104]) from the calibration protocol
8. Adopt the "Zero balance" (0x8000:25 [} 104]) from the calibration protocol
Calibration
The calibration is of great importance for the accuracy of the system. In order to increase this, the
filter should be set as strong as possible over the entire calibration phase. It may take several sec-
onds before a static value is obtained.
EP3356-0022 Version: 1.1.0
Commissioning/Configuration
81