Micrologix 1500 on DH+

[Sergei Troizky 26]

Is it possible? If yes, what is the simplest way?

[Eddie Willers 2]

The *simplest* way is to attach a 1770-KF2 to the serial port of the MicroLogix 1500. It's also VERY expensive, and quite bulky. There are third-party DH+ interfaces available that cost less then the KF2, such as those from www.protocolconverter.com. MicroLogix controllers were just never really intended to go onto DH+ networks, that's why there is no cheap or modular interface for them. The most requested network these days is usually Ethernet.

[gravitar 3]

Would it even work to connect a KF2 to the micrologix? My understanding of the KF2 is that it is analogous to the AIC+.. In both cases, the host device must be able to communicate in the desired protocol, even though they only connect over RS232. The micrologix 1500 doesn't have any DH+ capability, does it? I think what would have to happen if someone would need to connect to a micrologix from a DH+ network, is to use the DH+ to DH485 bridge card. It was, uhh.. 1771-KA5? something like that. I know there is a bridge card that sits in a 1771 rack, there might have been a standalone one as well. But this would be a very expensive option as well.

[Eddie Willers 2]

The 1761-NET-AIC only does physical conversion from RS-232 to RS-485 electrical signalling. It does no protocol conversion. The 1770-KF2, conversely, actually converts from DF1 Full Duplex protocol on RS-232 to DH+ protocol on DH+ signalling. The MicroLogix still thinks it is "speaking" DF1 Full Duplex protocol, but the 1770-KF2 device converts that traffic to the DH+ protocol. It's a little like asking if you can put a Chrysler 440 Hemi into a lawnmower. While it might be physically possible, the lawnmower isn't really built for the racetrack. I suspect Sergei has an application where his customer has a small application but a DH+ network installed in their plant, so they want to use the inexpensive MicroLogix 1500 controller but also have the PLC-5 networking on DH+. It would probably be cheaper to put in a small PLC-5 or SLC-5/04 than to try to connect a MicroLogix to the DH+ network.

[JesperMP 2]

The easiest way to get increased comms capability with the MicroLogix'es is to add a 1769-NET-ENI. It converts from DF1 to Ethernet, almost like the KF2 converts from DF1 to DH+. It is not cheap but a lot less expensive than a KF2. You can send messages to other AB PLCs on Ethernet, SLC5/05's, PLC5/xxE, other NET-ENI's etc. However, there are a limit to how many connections and traffic that a NET-ENI can pass. If that helps in your situation I dont know. Maybe you can tell us more what the ML has to connect to in the other end. Edited 1 Jun 2005 by JesperMP