Modicon TSX Micro 3721001 - CPU Fault - Modules or Base Unit?

[andyz 0]

Hello - we run a car wash that is controlled by a Modicon TSX Micro 3721001. It is indicating a CPU fault. I've attached a picture of the unit in place, with the LEDs lit. I have ordered a new base unit (2nd picture). I haven't tried it out yet, but it is tested working. I am hoping a base unit replacement will solve the problem, but wondering if it it possible the problem could be in the modules? I did not order those but now wondering if I should have... If the issue could be with the modules, is there a way to test which one it would be so I won't need to order all 4? If it coult be a module, I might order that now as I am in a rush to get back in service. Thanks for any guidance! Andy

[Crossbow 277]

If you had the software to get online with it there may be more information available on the problem.

[RDA 1]

If probleam and software that he expired and maybe did a useless work and money spent. Under all circumstances however, you must have the source code to be downloaded into the new CPU

[acpi 11]

Morning, It is hard to see on the pictures but it seems all the leds are lighted, This is not good at all... usually it means the plc is out of service and you will not be able to go online. The good news is that you have a memory cartridge and the program should be inside so normaly all you have to do is to plug the new base plc with all modules and the cartridge. JC

[PLCRune 2]

It is no memory cartridge on this photo.. But your problem is that the cover over where to put memory cartridge is not in place. Turn off power and push the cover back in. Repower. I'am not sure if this CPU maybe deletes its program when the cover is removed. Some did. R

[acpi 11]

That's right, there's no memory cartridge, I looked too quickly the first picture . That could explain the lighted leds but normally you can't lose the program if the cover is removed. There are some sort of metal springs on the cover, you have to check if the contact inside is ok otherwise the machine can not go in run mode. JC

[andyz 0]

Thanks for the help, everyone! The module is run without the cartridge - the slot is always empty as you see in the pic. You are right that all the leds are lit - though they are not typically, even with the cartridge out. The top led is usually lit and the terminal led lights intermittently. acpi - it sounds like from your post that I'm on a hardware fault and on the road to replacement! My service technician holds the memory cartridge and reloads the program when/if the PLC loses the program. I wish I could download the program to my own memory cartridge so I didn't have to pay the tech every time to reload the program but I am having some trouble finding a cartridge. Thanks again. Andy Edited 5 Oct 2015 by andyz

[cHud 24]

Another thing to check is the "reset"button just above the memory cartridge. Sometimes they get stuck in the pressed position and all the lights will be on then. If you press it you will feel it click.If not then it is stuck and you need to fiddle with the thing to get it unstuck

[janb 0]

On 05.10.2015 at 9:12 AM, cHud said:

Another thing to check is the "reset"button just above the memory cartridge. Sometimes they get stuck in the pressed position and all the lights will be on then. If you press it you will feel it click.If not then it is stuck and you need to fiddle with the thing to get it unstuck

it helped me. Thank you.