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Black Box IC821A RS-232 to RS-422/485 converter with optical isolation

Black Box Corporation

Black Box Corporation IC821A RS-232 to RS-422/485 converter with optical isolation

SKU CH-9SKE-7EC2Z MPN IC821A

Converts RS-232 signals to RS-422 or RS-485 with optical isolation

  • TypeConsumer Electronics
  • Converts RS-232 signals to RS-422 or RS-485
  • Optical isolation protects equipment from ground loops
  • Compact IC821A unit fits tight installation spaces
  • Supports both RS-422 and RS-485 communication modes

RS-232 to RS-422/485 converter

The Black Box IC821A converts RS-232 signals to RS-422 or RS-485 formats. Optical isolation protects connected equipment from ground loops and voltage spikes. It suits industrial automation, building management and legacy serial device integration where reliable long-distance communication is required.

Upgrading from non-isolated

This unit replaces basic cables or converters that lack isolation or multi-drop support. The jump is worth it when cable runs exceed RS-232 distance limits, when multiple devices share a bus or when electrical noise threatens data integrity. Buyers needing USB connectivity or protocol conversion beyond RS-422/485 should look elsewhere.

Highlights

  • Converts RS-232 signals to RS-422 or RS-485
  • Optical isolation protects equipment from ground loops
  • Compact IC821A unit fits tight installation spaces
  • Supports both RS-422 and RS-485 communication modes

Specifications

BrandBLACK BOX NETWORK SRV
TypeConsumer Electronics
Shipping weight0.23 kg
Package size102 × 76 × 13 mm

Questions about this item

What connectors does the IC821A need on the RS-232 side to fit my equipment?

The IC821A uses a standard RS-232 interface for connection to your host device.

How is the IC821A installed, and what step is often missed?

Connect the RS-232 side to the host, the RS-422/485 side to the bus, then apply power; the optical isolation activates automatically.

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