Hioki SW9001, Instruction Manual

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143
Accuracy Calculation Example
11.3 Accuracy Calculation Example
This section describes how to calculate the combined accuracy of the device and a connected
measuring instrument.
This process consists of calculating the measurement influence for each measuring instrument
(target instrument) used in the combination.
The measurement accuracy when using the device and a module is calculated using the following
formula:
Combination measurement accuracy = Instrument ac combination measurement influence
For more information about a given module’s measurement influences, see the module’s
specifications.
• SW9001
"Measurement influence" (p. 131)
• SW9002
"Measurement influence" (p. 139)
Below shows an example of accuracy calculation.
Example 1: Use of the device in combination with the BT3562A
Used module SW9001
Instrument BT3562A
Ω
V function, 3 m
Ω
range, 6 V range, sampling SLOW
Measurement value 1 m
Ω
, 4 V
Resistance measurement accuracy = BT3562A resistance measurement ac SW9001
measurement influence (BT3562A 3 m
Ω
range)
= (±0.5% rdg. ± 10 dgt.) + (±0.1% f.s.)
= (±0.5% × 1 m
Ω
+ 0.0010 m
Ω
) + [±(0.1% × 3.1000 m
Ω
)]
= (±0.0060 m
Ω
) + (±0.0031 m
Ω
)
= ±0.0091 m
Ω
(total error)
Voltage measurement accuracy = BT3562A voltage measurement ac SW9001
measurement influence (all BT3562A voltage ranges)
= (±0.01% rdg. ± 3 dgt.) + (±5 µV)
= (±0.01% × 4 V ± 0.00003 V) + (±5 µV)
= (±0.00043 V) + (±5 µV)
= ±0.000435 V (total error)
11
Multiplexer Module
HIOKI SW1001A961-04