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ADU71 USB to Current Output interface ( 4-20mA, 0-20mA Transmitter)

  ce.jpg (2571 bytes)See ADU72 USB to Current Input  ( 4-20mA, 0-20mA Receiver )

ADU71 USB to Current Output Interface ( 4-20mA, 0-20mA Transmitter )

The ADU71 USB to Current Output Interface ( Transmitter ) is a USB bus powered current loop source for driving 4-20mA or 0-20mA input devices. The ADU71 can also be used with external resistors to provide 1-5VDC, 0-5VDC or 0-10VDC signals for variable frequency drives, valves etc. The ADU71 internally generated 24VDC loop supply eliminates the need for an external loop power supply. This low-cost USB to Current Output Interface is easy to use with VB, and Visual C++ or .NET via standard HID drivers included with Windows 98,2000,XP,7,8. A mini-driver ( DLL )* is also provided allowing control using standard ASCII commands using familiar readfile , writefile commands. The ADU71 includes a 10' USB cable and is available in a flange mount enclosure with a DIN rail mount option.

Click here to view sample connection diagrams.

Click to view the ADU71 operating commands.

Download ADU71 User Manual ( 900K )

* View AduHid.dll  on-line software develoment kit ( SDK ) on our Programming page.

Key Benefits, ADU71  USB to Current Output Interface ( 4-20mA, 0-20mA Transmitter)

  • Provides a standard powered current loop output of  4-20mA or 0-20mA.
  • Drives 4-20mA, 0-20mA devices or 1-5VDC, 0-5VDC or 0-10VDC inputs using external resistors.
  • Ideal for controlling variable frequency drives ( VFD ), valves etc.
  • Internal isolated 24VDC supply derived from USB bus. No need for external loop power supply.
  • Programmable slew rate from 1ms to 10 seconds.
  • Programmable host watchdog function.
  • Loop error detection.
  • Over temperature detection
  • 2500V Isolation to loop.
  • Bus Powered
  • High retention USB Connector
  • CE Marked
  • Bi-colour LED status indicator.
  • High quality cage-clamp type terminal blocks.
  • Uses standard HID drivers included with Windows 98SE,2000,XP,7,8 32-bit or 64-bit
  • Mini-driver ( DLL ) provided for use with VB,VC, .NET, LabVIEW and TestPoint and others. See Programming Page
  • Meets IEC61000-4-2 ESD protection for USB port.
  • Available in flange ( standard ) or DIN rail mount.

Specifications, ADU71  USB to Current Output Interface ( 4-20mA, 0-20mA Transmitter)

General ADU71
Supply Voltage NONE ( Bus Powered )
USB Supply Current ( Loop Disabled )

USB Supply Current ( 20mA Loop Current )

65mA  Typical        75mA Max

180mA Typical        200mA Max

Operating Temperature -25C Min  to  85C Max
Current Loop Output
Resolution 16 Bits
Range 4-20mA or  0-20mA, programmable
Total Unadjusted Error -0.3%FSR MIN   +0.3%FSR MAX
Full Scale Error -0.2%FSR MIN   +0.2% FSR MAX
Temperature Stability +/- 16 ppm FSR/Degree C
Slew rate 1ms to 10s  Programmable
Isolation 2500V
Internal Loop Power Supply
Voltage 24V Nominal
Isolation 2500V
Loop Compliance Voltage 21V Minimum
Special Functions
Internal Loop Power Supply Internal 24VDC supply eliminates need for external loop power supply.
Mounting Options Flange Mount ( STANDARD ) , DIN Rail

Pricing,  ADU71  USB to Current Output Interface ( 0-20mA, 4-20mA Transmitter)

( Includes 10' USB cable )

Description $US
ADU71 $169.00
ADU71 QTY 5-9 $158.00
ADU71 QTY 10+ $149.00

IMPORTANT: Specify mounting option when ordering.  -FLANGE ( standard )  or -DIN . See Mounting Options for details.

For example: ADU71-FLANGE      ADU71-DIN 


ADU products do not ship with drivers on floppy or CD-ROM. Drivers, including complete SDK can be downloaded or viewed on-line in the Programming Section.

Pricing indicated is for ADU71 USB interface with flange mount enclosure, printed user manual,  and a 10' USB cable.  

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Ontrak Control Systems Inc.
764 Notre Dame Ave., Unit #1
Tel: (705) 671-2652 General Information Sales or Support
Sudbury,Ontario Fax:(705) 671-6127
CANADA P3A 2T2    
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