Analog Data Bits - Automation Direct DL405 User Manual

Analog Data Bits

The first twelve bits of each V-memory
location represent the analog data in
binary format. The remaining four bits
are not used and are ignored by the
module.
Bit
0
1
2
3
4
5
Since the module has 12-bit resolution, the analog signal is made of 4096 counts
ranging from 0 – 4095 (2
get a 0V signal, and 4095 to get a 10V signal. This is equivalent to a binary value of
0000 0000 0000 to 1111 1111 1111, or 000 to FFF hexadecimal. The following
diagram shows how this relates to each signal range.
+10V
Each count can also be expressed in
terms of the signal level by using the
equation shown. The following table
shows the smallest signal change that
occurs when the digital value is
increased.
0 to 10V
1 to 5V
4 to 20mA
Value Bit
1 6
2 7
4 8
8 9
16 10
32 11
12
). For example, with a 0 to 10V scale, you would send a 0 to
0 – 10V
0V
0 4095
Signal Range
D4-02DA 2-Channel Analog Output
MSB
1 1 1
5 4 3
Value
64
128
Unused
256
Bits
512
1024
2048
1 – 5V
+5V
1V
0 4095
Resolution + H * L
H = high limit of the signal range
L = low limit of the signal range
Span Divide By
(H – L)
10V 4095
4V 4095
16mA 4095
V40501 & V40502
LSB
1 1 1 9 8 7 6 5 4 3 2 1
2 1 0
– data bits
4 – 20mA
20mA
4mA
0 4095
4095
Smallest Change
2.44 mV
0.98 mV
3.91 mA
11–9
0