System Requirements

Personal Computer

Although any PC will work, we recommend a Compaq Deskpro 2000 with Microsoft Windows 95. The Compaq computers are shipped without the "bells and whistles" that conflict with the communication polling routines.

If you must use a PC other than the Compaq Deskpro 2000, you MUST format the hard drive and re-install Windows 95. This is required in order to remove any superfluous software that may interfere with the communication routines.

Communication Interface

A special device is required to interface the PC's RS-232 communication port with the RS-485 port at the IA.

We recommend the Black Box RS232C - RS485 converter model IC-109A-R2. This device has proven to be extremely reliable and easy to install and configure.
One of these devices is required for each serial port used. Also, one of these devices is required at each IA/1 as this type of IA does not have a built - in RS485 port. To connect the Black Box converter to the IA/1, you need to purchase an RS-232 cable (25 pin male to 25 pin male).

The converter may be purchased from Black Box Corporation:

Customer Service
Black Box Corporation
1000 Park Drive
Lawrence, PA 15055
Phone: (412) 746-5500

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The best cable for use with RS485 communication is Belden 9502. This cable consists of two twisted pairs, individual shield, and an overall shield.

See the wiring example below:

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