Using Modbus, what is the MAXIMUM level of precision available?
A. 8-bits
B. 16-bits
C. 24-bits
D. 32-bits
Answer
The correct answer is B, 16-bits.
Common Modbus uses two 8-bit bytes for each data register.
2 x 8 bits = 16 bits
To achieve more precision special programming or a specialized version of Modbus is necessary.
Eight bits is less precise than 16-bits; 24-bits and 32-bits require uncommon means to achieve.
Reference: Bella Liptak, Instrument Engineers Handbook, Volume 3 (3rd Edition), Process Software and Digital Networks; ISA, 2002
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C. Risk reduction.
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A. Thermocouple.
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