Mitsubishi FX2NC

[cjh]

Anybody ever see a problem where the error LED turns on when you plug in the SC-09 programming cable? I can't connect to the PLC either. If I take the cable out, the error LED goes away???

 

[panic mode]

that sounds interesting...
i didn't use FX2NC but SC09 should be the right cable.
are you sure this cable is ok? SC09 draws 5V power from the
PLC (used for converter chips inside the bulky end of the SC09).
if the cable is damaged and you plug it to plc, it is quite
possible that plc detects it and acts as you have described.

 

[cjh]

I feel pretty confident that the cable is fine. I can plug it into a FX2N-32MT and it works fine. It's only the FX2NC that it doesn't like.

 

[Pierre]

We have encoutered a similar problem before.

The problem was with the stacks of printed ccts inside the PLC.

When we would PUSH the DIN connector in place it would short cct the power internal power supply. We we would PULL it out the short was disengaged.

We only found it when we tryed to make one good unit out of many dead ones. That was 6 month later

We screwed and snapped the parts back in place and all was OK.

This is a wild guess but you can try!

Open it and reconnect the SC09 cable while monitoring the 5 Vdc supply.

 

[Goody]

Nice one Pierre, and I believe it will be the fault.

I was stumped with the problem then read your reply and remembered I too had a similar fault a few years back.

All of the lights were going off on the front of the plc, but give it a squeeze (yeah, a squeeze with fingers on top and thumb underneath) and it all came back on and ran for weeks before happening again.

I took it to bits several times but found no particulat fault - in the end just did what I should have done at the start - swapped it out.

 

[panic mode]

That sounds just like problems I had with my Keyence vision system
or J2S Mitsubishi servos... They sure squeeze everything in and
make it look nice but not robust.

 

[Shawn Cassidy]

I've had a very similar problem with these PLCs. When I have an E50/100 series screen connected the screen would sometimes turn off on it's own. We found out that it was losing power at the PLC connector. We had to put a small 5v power supply just for the screen since the supply from the plc was not reliable.