Micrologix 1500

This is probably a stupid question, as I know nothing about plc programming. We have a machine that runs with a Micrologix 1500 controller and a touch screen of some sort. The machine was running great one day, then the following day, we powered it on and the machine won't run. The screen turns on with all the presets still there, but it won't control anything. The battery light is flashing on the ML1500. The power to the machine is killed after every use. I don't know how long the battery light has been flashing, or if would even cause an issue. If the permanent battery in the controller is shot, will the controller still hold the program in its memory? If so, then I'm assuming the problem is probably somewhere else in the machine.

welcome to the forum ...

the battery LED is "FLASHING" ??? ... can you take another look at that please? ...

I don't doubt what you're saying - but that would be a new one on me ... usually the battery LED is either OFF (which is "good") or it's ON solid red (which is "bad") ...

by the way - here's a link to the 1500's User Manual ...

http://literature.rockwellautomation.com/idc/groups/literature/documents/um/1764-um001_-en-p.pdf

I'm afraid that it's not going to do you much good - unless you have the RSLogix500 software available ...

have you considered calling in a vendor to help with this? ... if your livelihood depends on this machinery - that might be the safest thing to do ... (this is not a sales pitch by the way) ...

The ML1500 stores its program normally in battery backed up memory.
There's a memory module you can add to the ML1500's that can be used to store the program in a non-volatile fashion.

If the battery is dead and you don't have a memory module, you've probably lost the program and need to reload from your backup.

the battery LED is "FLASHING" ??? ... can you take another look at that please? ...

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I'll take a look. It's probably not flashing.

have you considered calling in a vendor to help with this?

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Contacting the vendor is not an option. They went out of business while installing the machine years back.

If the battery is dead and you don't have a memory module, you've probably lost the program and need to reload from your backup.

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I'm not positive if we have the memory module. I would hope the company that installed it would be smart enough to use one. I'll check and see if I can spot one in there. As for reloading the program, our backup was stored on a 3 1/2" floppy and has been sitting in a drawer for quite a number of years. Tried pulling the information off it yesterday to no avail.
I appreciate all the help guys! I'll get back to you on these questions and let you know what I find out!

Contacting the vendor is not an option. They went out of business while install the machine years back.

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no, I'm sorry – but you've misunderstood ... I said (and meant) "A" vendor - not necessarily "THE" vendor ...

specifically, you need someone who has a working copy of RSLogix500 software on their computer - and the proper know-how to try and get you back up and running again ...

best case scenario: the program is still inside your controller - and you just need someone knowledgeable – and properly equipped - to help you get the system back up and running ...

worst case scenario: the program has been lost – and there are NO backup copies lying around anywhere ... in that case you'll need someone knowledgeable – and properly equipped - to rewrite the program and help you get the system back up and running ...

this could get real ugly – real quick ... good luck with it ...

Tried pulling the information off it yesterday to no avail.

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about the only "useful" way to pull the information off would be by using RSLogix500 software ...

just so that you'll know - even if you COULD retrieve the program from that disk yourself - you still wouldn't be able to download/send/store the program into the controller without having a copy of the RSLogix500 software that I keep mentioning ...

my friendly advice is to leave that backup disk alone - until someone properly equipped can try to retrieve the program from it ... depending on the complexity of your program - and whether or not it needs to be completely rewritten - that disk might represent quite a few thousands of dollars to you ...

question: did you happen to notice the presence of a file with an extension of RSS on that disk? ... that would be "GOOD NEWS" - as long as the file is still viable ... but honestly - if I were you - I wouldn't tinker around with the disk again just to find an answer to that question ...

no, I'm sorry – but you've misunderstood ... I said (and meant) "A" vendor - not necessarily "THE" vendor

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I did misunderstand. Sorry.

best case scenario: the program is still inside your controller - and you just need someone knowledgeable – and properly equipped - to help you get the system back up and running

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There is a memory module in the controller. I don't think the program has been lost.

did you happen to notice the presence of a file with an extension of RSS on that disk?

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There is a file with the .rss extension. Which is the program file for RSLogix. The one I can't get off the disk is a file with .epj extension. Which from my research, I think is the program for the HMI.
There are electromagnetic proximity sensors that turn on and off on the PLC when triggered, but nothing shows as changing on the HMI. I'm wondering if there is a communication problem between the HMI and the controller. The Comm light is lit up on both the HMI and the controller though, which is a bit odd to me.
From this point we will most likely have to contact a vendor to take a look. Thanks for all your help guys. Much appreciated.

best of luck with it - and please come back and let us know how it finally turns out ... this type of problem pops up a lot more often than you'd think ... knowing the final outcome might help someone else in the future ...

just as a final thought ...

this probably will NOT help - but I'd do it anyway ...

first - make SURE that the machine is SAFE to experiment with ...

then (and ONLY then) open EACH and EVERY screen on the HMI - and press and then release EACH and EVERY button - on EACH and EVERY screen ...

write back and let us know if it helps - and I'll explain ... if it doesn't work (and it probably won't) then no sense in wasting the time to talk about it ...

Dumb question, but is your PLC in Run mode?

first - make SURE that the machine is SAFE to experiment with ...

then (and ONLY then) open EACH and EVERY screen on the HMI - and press and then release EACH and EVERY button - on EACH and EVERY screen ...

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We had previously tried that.
The machine is a log notcher that has 2 router bits that move on multiple axes. The log is put into a clamp that can rotate 180°. The machine won't run without the clamp being down. We've looked around for a sensor that tells the controller the clamp is down, but can't find anything. When pushing the clamp button on the HMI nothing happens. So it could possibly be a faulty sensor. Without knowing what kind or where that sensor is, it will be difficult to test.
I still find it a bit odd that on the HMI I/O screen, all the home sensors are triggered permanently as on and do not change. I would assume those should change as the sensors are triggered on or off. They will trigger on and off on the controller, but not the HMI. We tried pressing all the buttons while keeping an eye on the DC output lights on the controller and nothing lights up. I would assume that when you push the correct button, it should trigger a voltage output to the proper places correct?

Dumb question, but is your PLC in Run mode?

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I would assume it would be in run mode? Nothing has been tampered with on the PLC.

Well, if it faulted or transferred back from the memory module, it may no longer be in run mode.
Check the LEDs on the front ,
Power should be Green
Run should be Green(if it isn't then it is in program or remote program)
Fault should be not lit.

I would assume it would be in run mode? Nothing has been tampered with on the PLC.

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Not necessarily...

As dravik points out, the RUN LED should be lit GREEN on the front of the controller. Is it? (See attachment)...

In the program, status bit S:1/12 - "On Powerup Go To Run" would have to have been set originally for the controller to always go straight into RUN Mode when the machine is power cycled. If this bit is not set then you have to use either the Mode switch under the left cover, or use RSLogix 500 software, which you do not have.

To go to RUN Mode, flick the switch to Prog Mode and then back to RUN Mode.

Another thing to note...

When you power on the controller, and it has a memory module that has been set to load from the module on powerup, then you should see the RUN LED flashing Green for a while as the transfer from the memory module into the processor's memory is active. Then it should go to RUN Mode, or not.

Regards,
George

I would assume that when you push the correct button, it should trigger a voltage output to the proper places correct?

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no, most HMIs don't work like that ... instead (this is in GENERAL terms) ...

when you PRESS the "button" on the screen, the HMI sends ONE message over the communication network to the PLC – which puts a status of ONE into a bit box inside the PLC ...

then ...

when you RELEASE the "button" on the screen, the HMI sends ANOTHER/SEPARATE message over the communication network to the PLC – which changes the bit's status from a one to a ZERO ...

so sometimes ...

you PRESS the "button" – and the ONE gets sent and received ... BUT ... once in awhile some type of communication glitch happens just before you RELEASE the "button" ... oops! ... the "change-the-bit-back-to-a-ZERO" message doesn't go through – so the bit in the PLC gets "stuck" with a status of ONE ...

the "press and release" trick will sometimes send the ZERO message – and SOMETIMES get everything back to working again ... it's a long shot – but usually worth a try – as long as you can make the machinery SAFE while you're pushing all of those buttons ...

Well, if it faulted or transferred back from the memory module, it may no longer be in run mode.

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Not necessarily...

As dravik points out, the RUN LED should be lit GREEN on the front of the controller. Is it? (See attachment)...

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You guys were correct. It faulted and switched out of run mode. After a toggle of the switch and a reboot, run light came on exactly as you described. The machine is now responsive and running. Thanks for all the help everyone has provided. You probably saved us a good chunk of change. It's appreciated more than you could know!

Great!

Now get some PLC training as you're likely the goto person for anything PLC related forever