Appendices
A - 14
NX-series Analog I/O Units User’s Manual for Analog Input Units and Analog Output Units (W522)
Unit name
Analog Input Unit (current input type)
Model
NX-AD3208
Number of points
4 points
External connection
terminals
Screwless clamping terminal block (12 ter-
minals)
I/O refreshing method
Switching synchronous I/O refreshing and Free-Run refreshing
Indicators
TS indicator
Input method
Differential input
Input range
4 to 20 mA
Input conversion range
-5 to 105% (full scale)
Absolute maximum
rating
±30 mA
Input impedance
250
Ω
Resolution
1/30000 (full scale)
Overall
accuracy
25
°
C
±0.1% (full scale)
0
to
55
°
C
±0.2% (full scale)
Conversion time
10
μ
s/point
Dimensions
12 (W) x 100 (H) x 71 (D)
Isolation method
Between the input and the NX bus: Power
= Transformer, Signal = Digital isolator (no
isolation between inputs)
Insulation resistance
20 M
Ω
min. between isolated circuits (at
100 VDC)
Dielectric strength
510 VAC between isolated circuits for 1
minute at a leakage current of 5 mA max.
I/O power supply
method
No supply
Current capacity of I/O
power supply terminal
Without I/O power supply terminals
NX Unit power con-
sumption
• Connected to a CPU Unit
1.30 W max.
• Connected to a Communications Cou-
pler Unit
0.95 W max.
Current consumption
from I/O power supply
No consumption
Weight
70 g max.
Circuit layout
Installation orienta-
tion and restrictions
Installation orientation:
• Connected to a CPU Unit
Possible in upright installation.
• Connected to a Communications Coupler Unit
Possible in 6 orientations.
Restrictions: No restrictions
Terminal connection
diagram
Input disconnection
detection
Supported
AMP
AG
AG
to 4+
Terminal block
Input1
−
to 4
−
510 KΩ 510 KΩ
250 Ω
AG: Analog circuit
internal GND
NX bus
connector
(left)
I/O power
I/O power supply
−
I/O power
I/O power supply
−
NX bus
connector
(right)
AG
A1
B1
A8
B8
AG
AG
AG
AG terminal is connected to 0 V of analog circuit inside the Unit.
It is not necessary to wire AG terminal normally.
Input +
Input
−
Current Input Unit
NX-AD3208
Input1
−
Input2
−
Input3
−
Input4
−
Summary of Contents for NX-AD series
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