CAS NT-302A - Formula to Plan the Precise Weighing System

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4-2. Formula to plan the precise weighing system
This “NT-302A” weighing controller’s Max. input sensitivity is 0.45㎶ / Digit.
And for precise weighing system, the following formula must be satisfied.
Caution : “Input sensitivity” means Min. output voltage variation of weighing part to change
1digit. So, please do not make large input voltage to make reliable weighing system.
Single Load cell use
≤EⅹBⅹD
A : Load cell capacity(kg)
B : Load cell Voltage(mV)
D : Digit
E : affirmation Voltage of Load cell
N : Number of Load cell
0.45㎶
A
Plural Load cells use
≤EⅹBⅹD
0.45㎶
AⅹN
Example1.)
Number of Load cell : 1pcs
Load cell capacity : 500kg
Load cell Voltage : 2mV/V
Digit : 0.05kg
Affirmation Voltage of Load cell : 5.0V
Max. Capacity of Weighing System : 300kg
Then, estimation result for this weighing system with formula,
5000ⅹ2ⅹ0.05
= 1 ≥ 0.45㎶
The calculated value is larger than 0.45㎶,
so this system has no problem.
500
Example2.)
Number of Load cell : 4pcs
Load cell capacity : 500kg
Load cell Voltage : 2mV/V
Digit : 0.10kg
Affirmation Voltage of Load cell : 5.0V
Max. Capacity of Weighing System : 1,000kg
Then, estimation result for this weighing system with formula,
5000ⅹ2ⅹ0.10
= 0.5 ≥ 0.45㎶
The calculated value is larger than
0.45㎶, so this system has no problem.
500ⅹ4
Cautions
!