EMC INDUSTRIAL GROUP LTD
Inputs
MW61A_IM_ALL_SV6.09d_en
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Loadcell input (vessel weight)
Input settings
*
Q22311 AI1 response time [0.04 to 32]
8120, g1
0.50 s
The response time for the weight signal. A larger value will help reduce variations in the weight reading
caused by vibrations or movement on the weighing system.
Q22312 lever ratio
8130, g1
1.0000
The lever ratio adjusts the weight reading during calibration. It is the ratio of calibration weight (test
weight) to displayed weight (gross weight).
Q22313 4 or 6 wire connection
8128, g1
auto=0
Selects if the loadcell has a 4 wire or 6 wire connection to the instrument. If set to auto, it will power up
in 6 wire mode, but switch to 4 wire mode if there is no sense voltage detected.
Q22314 loadcell scan
8168, g7
0
Set to 0 for normal operation. Selects the number of loadcells to be individually measured. Loadcell in-
puts P, Q, R, and S are multiplexed, measuring each one for the ‘AI response time’. The individual sig-
nals are saved in ‘AI1 signal P, Q, R & S’. The average signal is saved in ‘AI signal’.
Calibration with weights
The basic procedure is to remove all weight from the weighing system and set the zero setting to 0.
Then a known weight is applied to the weighing system and the span setting adjusted to this weight.
*
Q22321 AI1 zero (remove all weight & set to zero)
8910
8
(shows weight) kg,t,g
*
Q22322 AI1 span (apply weight & enter weight value)
8912
8
(shows weight) kg,t,g
Calibrate loadcell
This is often the easiest method of calibration. It is useful to detect problems with the weighing mecha-
nism which may not otherwise be shown using other calibration methods. It is also a quick method
which can be used at anytime to check the loadcell and weighing system.
1.
Press the Q key to access the setup menu.
2.
Key in the quick key code 22321 to select the ‘AI1 zero’ step.
3.
Make sure all material and test weights are removed from the weighing system.
4.
Press the EDIT key. (If editing is locked, key in the password 111 and press ENTER).
5.
Press the 0 key followed by ENTER and wait while the display shows ‘Calibrating, please
wait…’
6.
Press ENTER twice to move to the ‘AI1 span’ step. (Or press the DOWN key).
7.
Apply the known test weight.
8.
Press EDIT and enter the value of the test weight followed by the ENTER key and wait while
the display shows ‘Calibrating, please wait…’.
If possible, remove and apply the test weights several times checking the weight reading
each time. Make sure the weight reading is within acceptable error limits. If not there may be
a mechanical fault which should be fixed before proceeding with the calibration. Repeat the
calibration process if necessary. (To return to the ‘AI1 zero’ step, press the UP key).
9.
Press and hold the BACK key to return to normal operation.
Direct loadcell calibration
Q22331 loadcell capacity (sum of the capacity of all loadcells)
9
8122
1000 kg,t,g
Set to be equal to the total capacity of all the loadcells in the weighing system. If there are two 50 kg
loadcells, this setting should be 100 kg.
This setting can be adjusted even if the transmitter has been calibrated with test weights, and it will not
alter the calibration. If set correctly, the ‘system sensitivity’ and ‘deadload’ settings will then show how
the instrument has been calibrated.
Q22332 system sensitivity (average sensitivity of all loadcells)
8124
2.00000 mV/V
Shows the loadcell sensitivity (if the ‘loadcell capacity’ has been set correctly first).
If calibrating without test weights, set this value to the loadcell sensitivity. If there is more than one
loadcell and if each loadcell has a slightly different sensitivity, use the average value. For example, if
there are two loadcells with sensitivities 2.003 and 2.007 mV/V, set the ‘system sensitivity’ to 2.005
mV/V.
Q22333 deadload (dead weight on loadcells)
8126
0 kg,t,g
Shows the approximate dead weight on the loadcell(s), provided the ‘loadcell capacity’ has been set
correctly first.
If calibrating without test weights, then set this value to the weighing system’s weight when there is no
material load.
8
Entering a value initiates a calibration.
9
WARNING: Altering loadcell capacity will NOT change the loadcell calibration, but will re-scale the system sensitivity and deadload
values. Altering the system sensitivity or deadload values WILL change the loadcell calibration