E L C O p e r a t i o n M a n u a l
F o r m o r e i nf o r m a t i o n v i sit :
w w w. e a t o n . c o m
MN05003006E
1-124
3.2.3.9 A/D, D/A Conversion Curve
Adjusting A/D Conversion Curve of CH1 ~ CH4
You can adjust the conversion curves according to the application requirements by changing
the Offset value (CR#28 ~ CR#31) and Gain value (CR#34 ~ CR#37).
Gain: The voltage (current) input value corresponding to digital value 16,000.
Offset: The voltage (current) input value corresponding to digital value 0.
z
For voltage input Mode0/Mode2: 0.3125mV = 20V/64,000 = 10V/32,000
Equation:
(
)
Offset
Gain
Offset
V
V
X
Y
−
⎟⎟
⎠
⎞
⎜⎜
⎝
⎛
−
×
×
=
32000
)
(
10
)
(
16000
Y=Digital value, X=Voltage input
z
For voltage input Mode1/Mode3: 0.15625mV
= 10V/64,000 = 5V/32,000
Equation:
(
)
Offset
Gain
Offset
V
V
X
Y
−
⎟⎟
⎠
⎞
⎜⎜
⎝
⎛
−
×
×
=
32000
)
(
5
)
(
16000
Y=Digital value, X=Voltage input
z
For current input Mode4/Mode5: 0.625
μ
A = 40mA/64,000 = 20mA/32,000
Equation:
(
)
Offset
Gain
Offset
mA
mA
X
Y
−
⎟⎟
⎠
⎞
⎜⎜
⎝
⎛
−
×
×
=
32000
)
(
20
)
(
16000
Y=Digital value, X= Current input
z
For current input Mode6: 0.5
μ
A = 16mA/32,000
Adopt the equation of current input mode4/mode5, substitute Gain for 19,200(12mA)
and Offset for 6,400(4mA)
Equation:
(
)
6400
19200
6400
32000
)
(
20
)
(
16000
−
⎟⎟
⎠
⎞
⎜⎜
⎝
⎛
−
×
×
=
mA
mA
X
Y
Y=Digital value, X= Current input
