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Converter, RS-232 Serial To 20mA Current Loop converter, 64 Kbps


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Manufacturer Part No:
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Technical Datasheet:
A420   Datasheet
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RS-232 serial

20mA Current Loop converter


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Technical Docs (1)

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Product Overview

The A420 is a RS-232 To 20mA Current Loop Converter provides optical isolation and transient protection. The device is full duplex point-to-point communication using only 4 wires (one pair each for receive and transmit data). The device has optically isolated data lines and high speed data transfers, 19200bps over 400 metres and a maximum data rate of 64Kbps. The 20mA current loop breaks the ground loop at each end so the device is suitable for inter-building communications where different ground potentials can make RS-232 unreliable.
  • Uses Hewlett Packard opto-couplers for 20mA
  • Available as a pre-set, fully isolated pair (2500VAC for 1 minute)
  • Screw terminal connector on 20mA side
  • Current loop transmit and receive lines are switch selectable for ACTIVE and PASSIVE
  • Switchable DCE/DTE selection for RS-232 port
  • LED indicators for data activity
  • Can be used in multidrop environments
  • Optically coupled 20mA transmitter and receiver
  • Configurable RD and TD loops as Active or Passive
  • Reverse polarity protection
  • Standard DB25 used for RS-232 interface


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More stock available to supplier lead times which is approximately 27/09/21

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$183.16 ( $201.48  Inc. GST)

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