Minebea CSA-507C, Инструкция по эксплуатации

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18
5 − 3 − 2. Confirmation of initial value
When the initial load(tare weight) is unclear, confirm it by the following procedures
：
1
Prepare the digital volt meter which can read 0.1 mVDC.
2
Measure the voltage(bridge power supply voltage) between A and C(C is minus) of the
instrument.
3
Measure the voltage(input voltage) between D and B(B is minus) of the instrument.
4
Calculate the input conversion value at the initial load through the below formula.
If the calculated value is “
＋
polarity”, the initial load will be plus, otherwise if the calculated
value is “
−
polarity”, the initial load is minus.
Referring to the paragraph 5 − 3 − 1, apply the external resistance.
(Input conversion value of the initial load)
＝
(Input voltage)
(Bridge power supply voltage)
Calculation example)
This is the example of the calculation method when the bridge power supply voltage is 5.000 V,
and the input voltage is 2.0 mV in the condition that initial load(tare weight) is applied as
follows
：
Bridge power supply voltage
：
5.000 V
Input voltage
：
2.0 mV
＝
5.000 V
2.0 mV
0.4 mV/V
(Input conversion value of the initial load)
＝
Therefore, accordint to the paragraph 5 − 3 − 1, Rz will be at 219 k
Ω
.