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$285.00 (USA and Canada only)

Availability: In stock
OBSOLETE RS-232 to RS-422/485 Converter 220 VAC

Production Specification

*** NOTE: This part is obsolete and no longer available when current stock is depleted. ***

RS-232 to RS-422/485 Converter 220 VAC

AC7A and AC7B

Power Requirements


115 VAC ± 10 VAC @ 50-60 Hz
220 VAC ± 20 VAC @ 50-60 Hz

Power Consumption

0.1 amps @ 115 VAC
5 watts (dissipation)

Temperature Range

0 °C to 70 °C
0 to 95% Humidity (non-condensing)

Optical Isolation

4,000 V between RS-232 and RS-422/485

RS-232 Interface

25-pin, DB-25 female connector

RS-422/485 Interface

Screw terminals or 9-pin, DB-9 female connector

Baud Rate

Up to 38,400 baud; 115.2KBd in Rev. L (AC7A)
and later and in Rev. C (AC7B) and later.

RS-232 Distance

Up to 50 feet

RS-422/485 Distance

Up to 5,000 feet at 38,400 baud (3,000 feet at 115,200 baud)


RS-422/485 full duplex over two twisted pairs and a ground.
Additional twisted pairs for RTS and CTS.
Also supports RS-485 2-wire mode. This requires user to
build a custom RS-232 cable.


Transmit, receive, RTS, CTS, and power

Agency Approvals CE; RoHS; UKCA


AC7A/B Adapter Card Data Sheet

The AC7A/B is a stand-alone adapter card that converts RS-232 serial communication to RS-422/485 serial communication, which is directly compatible with the Optomux family of intelligent brain boards.

AC7A - AC7B Users Guide

This document gives instructions for installing the AC7A/B adapter card in an Optomux network in 4-wire RS-422/485 mode with a PC and how to communicate with equipment other Optomux.

No downloads are available for this product.
No videos or demos are available for this product.