STANDARD ANALOG CURRENT
INPUT MODULES
Features
Single channel of optically-isolated current-to-digital
>
conversion
AD3T and AD2T modules offer additional channel-to-channel
>
isolation
“T” modules provide 4,000 Vrms channel-to-channel isolation
>
which eliminates ground loop problems
DESCRIPTION
Each Opto 22 AD3, AD3T, and AD2T analog input module provides a
single channel of optically-isolated current-to-digital conversion. The
AD3T and AD2T modules offer additional channel-to-channel
isolation. For the AD3 and AD3T modules, the nominal input range is
4 to 20 mA with an under/over range capability from less than 3 mA
to greater than 35 mA. The AD2T module has a nominal input range
of 0 to 20 mA with an under/over range capability from less than –
1.25 mA to greater than 35 mA. The “T” modules also provide 4,000
Vrms channel-to-channel isolation which eliminates ground loop
problems. These modules plug into a Classic Standard analog I/O rack
and are secured by a captive screw.
DATA SHEET
Form 443-191105
PAGE 1
AD3T
Part Numbers
Part Description
AD3 4 to 20 mA Input
AD3T 4 to 20 mA Input Isolated
AD2T 0 to 20 mA Input Isolated
© 2001–2019 Opto 22. All rights reserved. Dimensions and specifications are subject to change. Brand or product names used herein are trademarks or registered trademarks of their respective companies or organizations.
SPECIFICATIONS
AD3 AD3T AD2T
Input Impedance 249 Ohms 249 Ohms 50 Ohms
Nominal Input Range 4 to 20 mA 4 to 20 mA 0 to 20 mA
Over/under Range 3 to 35 mA 3 to 35 mA -1.25 to 35 mA
Accuracy 0.016 mA (0.1% of span) 0.016 mA (0.1% of span) 0.020 mA (0.1% of span)
Resolution 12 bits (0.0039 mA) 12 bits (0.0039 mA) 12 bits (0.0049 mA)
Response Time Full-scale step change in 3 ms
Isolation Transient
Input-to-Output
Input-to-Analog-Supply
Power Requirements
Ambient Temperature:
Operating
Storage
*Accuracy figures assume use of Gain and Offset commands.
4,000 Vrms
n/a
13 mA at +15 (+/- 0.25) VDC
7.5 mA at -15 (+/- 0.25) VDC
0 to 70 °C
- 25 to 85 °C
4,000 Vrms
4,000 Vrms
35 mA at +15 (+/- 0.25) VDC
35 mA at -15 (+/- 0.25) VDC
4,000 Vrms
4,000 Vrms
35 mA at +15 (+/- 0.25) VDC
35 mA at -15 (+/- 0.25) VDC
DATA SHEET
Form 443-191105
PAGE 2
© 2001–2019 Opto 22. All rights reserved. Dimensions and specifications are subject to change. Brand or product names used herein are trademarks or registered trademarks of their respective companies or organizations.
CONNECTIONS
AD3 Modules Using Shared Loop Service
NOTE: For connecting the AD2T
module, use AD3T module
diagrams and instructions.
AD3T: All of the lower A terminals on the
mounting rack are tied together. These
provide a convenient tie point for shared
loop source return. To use the AD3T
module with a common loop power
supply, connect any one lower A terminal
to the shared loop source “-”, then jumper
upper A to lower A for each AD3T.
DATA SHEET
Form 443-191105
PAGE 3
AD3 Modules Using Self-powered Transmitter
NOTE: For connecting the AD2T
module, use AD3T module
diagrams and instructions.
© 2001–2019 Opto 22. All rights reserved. Dimensions and specifications are subject to change. Brand or product names used herein are trademarks or registered trademarks of their respective companies or organizations.