AutomationDirect DL205, Руководство пользователя

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DL205 Analog Manual, 7th Edition Rev. D 16-26
Chapter 16: F2-8AD4DA-2, 8-Ch. In / 4-Ch. Out Analog Voltage Combination
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C
D
Module 16 Bit Output Resolution
Since the voltage output module has 16 bit reso-
lution, the analog signal is converted into 65536
(2
16
) counts ranging from 0-65535. For example,
a 0V signal would be 0, and a full scale 5V or
10V signal would be 65535. This is equivalent to
a binary value of 0000 0000 0000 0000 to 1111
1111 1111 1111, or 0000 to FFFF hexadecimal.
The diagram shows how this relates to the signal
range.
Each count can also be expressed in terms of the
signal level by using the equation shown.
Digital and Analog Output Data Value
Conversion
Sometimes it is useful to be able to quickly convert between the signal levels and the digital
values. This is especially helpful during machine startup or troubleshooting. For output ranges
with a minimum value of zero, the table below provides formulas to make this conversion
easier.
A = (D)(A
max
) / (D
max
)
D = (A)(D
max
) / (A
max
)
Output Value Comparisons: Analog, Digital, Engineering Units
The table to the right shows how the
output analog, digital, and engineering
unit values are related to each other.
The example is a measurement of
pressure from 0.0–140.0 PSI, using a
multiplier of 10 for one implied decimal
place.
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C
D
D = (6) 65535
10
D = (6)(6553.5)
D = 39321
5V/10V
0V
0 65535
0 -- 5V/10V
16 Bit Resolution
=
H
−
L
65535
H = high limit of the signal range
L = low limit of the signal range
5V / 65535 = 76 A per count
10V / 65535 = 152 A per count
16 Bit Resolution
µ
µ
• A = analog current output value
• A
max
= maximum analog value
• D = digital value from PLC CPU
• D
max
= maximum digital value
For example, if a 6V analog output
signal with a 0–10V output range, the
formula could be used to determine
the digital value (D) to be stored in the
V-memory location that contains the
output data.
Output Value Comparisons
Analog Range
Digital
16 Bit
E.U.
0–5V 0–10V
5 10 65535 1400
2.5 5 32768 700
0 0 0 0
Resolution Output Range If the digital value is known If the analog signal level is known.
16 bit
0–65535
0–5V A = (D)(
5
) / 65535 D = (A)(65535) / 5
0–10V A = (D)(
10
) / 65535 D = (A)(65535) / 10