No Outputs (Mistubishi Q-Series/GX Works2)...

[Ace1985]

Looking for a bit of help.

Our firm has a section of our machines subbed out to another company. They have a fairly old machine that PLC's battery died and they lost the software.

We've managed to source the software and I was supposed to re-load yesterday. I'm no PLC expert, still learning, have experience on GX developer and Mitsi PLC's.

The PLC is question was a Mitsi Q-series. The program given to us was on GX Works 2; which we have no experience of).

I re-loaded the software and got it to monitor. You could see inputs switching as buttons were pressed..

Looking at the software, the 'reset' button held for 5 sec would switch on a 'go home' marker. This was working as expected, but not all cylinders were going to home. When digging a bit deeper, there was no compressed air to the valves. There is a solendoid switch on the manifold which comes directly from an output of the PLC.

Going back to the panel, I followed solenoid cable back to output and noticed no outputs were illuminated. At this point, I checked the +24v on the cards, 24 was present. I then forced several outputs on in the plc, no output lights illuminated on the output cards.

Any suggestions to why we're not getting any outputs? I spent a good 4 hours going through the PLC parameters tabs, ensuring cards to rack set ups are correct etc etc

It's worth noting that this software was maybe not from GX Works2 originally, are there usually 'change over' issues? If yes, how could we get around it?

Any help appreciated.

 

[SceneryDriver]

Has the PLC been placed in RUN mode?


SceneryDriver

 

[Ace1985]

Yes. 100% in run mode.

If we put an input below a marker (which wont force) then force the input on, the output works.

If we remove that input then try to force output or marker that sets output, it doesnt switch on???

 

[Ace1985]

On a dummy set up with the same rack set up, i've read from in GX developer and same symptoms. No outputs will force on, but if you put an input in the rung and force that, it'll come on??

 

[controlsdude]

Simple stuff, in run mode, check to see that maybe the program needs some type of configuration set in the PLC to run the different files called out in the downloaded program.

1st Get a set of prints in front of you.
2nd Make sure you have all the proper power supplies and circuit breakers turned on for this machine
3rd Make sure the emergency stop is reset and the MCR is pulled in for the machine. Usually the MCR provides power to all moving output cards in some manner depending on voltage level of each card.
4th Now try to force an output on.
5th If this does not work check the output card to see if you have it at the card.
6th Some machines have other types of resets for the air, hydralics, mechanical lockouts, etc ... Probably would be wise to have an operator assist how the machine is ran.

 

[Ace1985]

Thanks for your reply.

I managed to bottom this out with pure man hours put into it.

1. During the translation from whatever it was originally written in to GXWorks2, the PLC type had changed. I was doing this in the parameters settings, but you have to send this to the PLC for them to change, yeah? This wasnt changing properly. When my engineer took a look at it, he told me you can change PLC type live in under the 'file' tab. Changing it here would allow me to force on outputs.

2. During the translation, the output adresses moved by a multiple of 10. So Y40 was now Y50. The output to the air solenoid was supposed to be Y57 (in the comments list) but was now Y67. When I forced this, we had air.

3. During the translation, there is alot of software missing! The software that brings on the Y57 output is missing, also other parts. Im in the process of re-writing it.

Hard work, but good learning..