Any CHEAP way to bridge a single MB+ into AB


Thread Starter

John Kelley

Hi All,

I have a customer with a almost total AB plant that bought a machine a couple of years ago with a Modicon Quantum controller. Now they want to integrate certain monitoring functions and make data available from the Quantum to controllers on the AB DH+ network.

Anybody know of a inexpensive way to do this? I don't need to bridge a whole bunch of PLCs, just a lonely Quantum out there. It's currently talking only to a HMI Panelmate 4000 via MB+ (or maybe serial... I'm not sure).

This machine needs to provide information to other systems up-line that control material delivery and such. I have a under-used PLC-5 sitting 20 feet from the thing so I've even considered using discretes to get cycling data and such, but that would be too darn easy.

Any suggestions... I'm an AB guy at heart and the customer only has MODSOFT (man, I hate Modsoft... NxT is better but they won't spring for it with only one machine).


John Kelley

ProLinx Gateways has a bridge that will convert Modbus to AB's DF1. It's only around $800. They can also do Modbus Plus to DF1 for about $1200.

Depends on your definition of cheap. You might want to try a ProSoft gizmo (check them out at

Eduardo Manuel C. Cipriano


It would be very impossible to communicate your Modicon PLC to Allen Bradley using DH+ network because DH+ is a proprietary protocol of
Allen Bradley, but if you want you can use Modbus Protocol and there are ready sample programs that you can download from their website, I have the same project but I will be communicating 3 SLC 503 processor to our Centum CS1000 DCS I've already tested Modbus and I highly
recommend it.

of course aside from using ethernet........

[email protected]

Eduardo Manuel C. Cipriano
Sr. Systems Engr.
Yokogawa Phils. Inc.

Curt Wuollet

Hi John

A simple handshake protocol on 10 lines or serial ports might be the cheapest option. Perhaps you could code one of the bit banging protos like I2C. That would be slow, but would only take a couple lines. This is another case where the simple virtual register mechanism I was talking about would be handy. And the lack of _any_ simple means is inexcusable on the part of two premier vendors. Does AB support Modbus/TCP?


> John,
I have done several of these the simplest is the ProSoft module. It will talk AB DF1(232) to MB(232), they will supply the code, requires
one slot in the AB

Good Luck