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Example:
zeroing the weight of the instrument with address 2
For the calibration you have to make sure that the system is unloaded or that the instrument
measures a signal equal to the mV in the same condition:
query:
$02z78(Cr)
response:
&02000000t\76(Cr)
If the zeroing works correctly the instrument sends the zeroed weight value (“000000”).
The calibration values are stored permanently in the EEPROM memory and the
number of allowed writings is limited (about 100000).
REAL CALIBRATION (WITH SAMPLE WEIGHT)
After the tare zero-setting, this function allow the operator to check the calibration obtained
by using sample weights and correct automatically any change between the displayed value
and the actual one.
Load onto the weighing system a sample weight, which must be at least 50% of the Full Scale, or
make so that that the instrument measures a corresponding mV signal.
The PC transmits
the ASCII string:
$aasxxxxxxckckCR
where
: s
................... calibration command (115 ASCII)
xxxxxx
...... 6 characters to indicate the value of sample weight
Possible instrument responses:
-
correct reception:
&aaxxxxxxt\ckckCR
-
incorrect reception or full scale equal to zero:
&&aa?\ckckCR
where:
t
................... character of gross weight identification (116 ASCII)
xxxxxx
...... 6 characters to indicate the value of current weight
In case of correct reception, the read value has to be equal to the sample weight.
Example:
calibration of the instrument no. 1 with a sample weight of 20000 kg:
query:
$01s02000070(Cr)
response:
&01020000t\77(Cr)
In case of correct calibration, the read value has to be “020000”.
