Micrologix 1000 not detecting I/O and RSLinx not detecting SLC 500

Hi everyone!

Hope everyone is having a great day. I just started out with PLC’s and by that I mean I was trying to understand how things work and how to get started with the programming aspect of it. I have a Micrologix 1000 PLC at work as well as a SLC 500 one. Problem is, nobody knows if this working or what all is needed to run these. I was trying to get started with the Micrologix 1000 PLC but I can’t figure out if this has an input card attached to it. There is a Compact Block I/O system beside it but I’m not sure if this is the input output card. When I try to configure it in RSLogix 500, nothing shows up, the I/O config tab is greyed out. So I decided to give SLC 500 a try, but the problem with it is that RSLinx is not detecting it. I’ve tried connecting to it using different cables (USB, DH+ etc) but nothing works. I’ve read the manuals and all but haven’t been able to figure out much.

I’m attaching relevant pics below. Can someone please guide me? Any help would be appreciated.



Thanks a lot!

Welcome to the Forum !

Picture 30_38 is of two different A-B Remote I/O adapters. The top one is a CompactBlock 1791R-8B8P, and the bottom one is a FLEX I/O 1794-ASB with a single 8-point 1794-IB8 input module.

These are made to connect to an A-B Remote I/O (RIO) protocol network. That's the blue-jacketed wire you see connected to the 3-pin plug on both modules. You're going to need a 1747-SN Remote I/O Scanner in your SLC-5/04 chassis to work with these.

Picture 30_47 is a MIcroLogix 1000 with DC Inputs, Relay Outputs, and AC power. This should not be connected to the Remote I/O gear in any way; the MicroLogix 1000 does not have any expandable outputs, just the 10 inputs and 6 outputs you see onboard. It's a limited-power controller but very easy to get started with.

Picture 30_58 shows the power supply and the SLC-5/04 controller. Do the BATT and RUN lights illuminate on the SLC-5/04 controller when you apply 120V to the power supply ?

Picture 31_18 is an analog Voltage combination input and output module, 1746-NI04V. You can also see a Thermocouple module, probably a 1746-NT4.

Picture 31_25 looks like another analog module, 1746-NIO4I. This one is a Current-loop combination Input and Output module, not a Voltage input and output module.

In the background you can also see the 1747-SN Remote I/O Scanner that you're going to need to run that CompactBlock and FLEX I/O.

One thing I've noticed is that some of the modules appear to be pulled slightly out of the chassis. NEVER remove or insert an SLC-500 module when the power is on; you will definitely fault the processor and face a 50/50 chance of damaging the module permanently.

It's probably easiest to start with the MicroLogix 1000. This model requires AC power, so check the wiring diagram and the terminal labels and see if it powers up.

You'll need a 1761-CBL-PM02 serial cable for the MicroLogix 1000. Get one from your A-B dealer or from TheAutomationStore.com.

To connect to the SLC-5/04 you just need a null-modem serial cable. The easiest thing to do is add a null-modem adapter to an ordinary straight-through cable.

Thanks for the reply Ken!

I should have mentioned before, I was able to connect to the Micrologix 1000 PLC but when I try to configure the I/O module as stated in the manual, all I see is a greyed out button. So wasn't able to proceed after that.

The modules for the SLC 500 were removed before powering it on. I was able to power on the SLC 500 too but RSLinx doesn't detect it even when I connect to it using a null modem serial cable. The fault light keeps blinking. When I try the auto detect button, it gives me a msg saying the detection has failed and asks me to check the switches.

Also, do you have an idea as to where I can get some RSLogix 500 tutorials? I really need to get started on the programming aspect and don't have much time. If I can atleast write a small program on it, that would be good.

Thanks again!

There are no I/O modules for the MicroLogix 1000. That CompactBlock and FLEX I/O have nothing to do with it.

What manual are you looking at ? The MicroLogix 1100, 1200, 1400, and 1500 all have expansion I/O but the 1000 does not.

Dunno what else to tell you about the SLC-5/04.

The serial port might be configured for something other than DF1 full duplex, or you might not have specified the correct COM port, or your serial cable might be damaged, defective, or incorrectly wired.

The "Auto Detect" feature doesn't work on all serial ports, especially cheap USB/RS232 units. Stick with the default settings of 19200 baud, 8/N/1 framing, DF1 Full Duplex, SLC/MicroLogix Device Type.

Thanks Ken for letting me know about the auto-detect feature. I will see if the default settings work out.

Also, do you know of any tutorials online that I can look at? I tried searching for some but didn't come across any that were helpful.

Thanks again!

Tutorials

The "Learn PLCs" link at the top of this page is a great place to start !

Probably the best SLC-500 focused website is The Learning Pit, which also sells the LogixPro simulator. It is very popular.

If I remember correctly, Micrologix 1000 can't be programmed online. You have to program it then download the program to it. that maybe why some of the option are greyed out.