Error Clearing FX2n48MT

[OG58]

Hello People, (first post newbie here)

I purchased a secondhand FX2n48MT and I have cleared the memory and the error light appears to be latched on in a special latch and register.

I can read and write programs to and from the plc and the plc is running the programs. Any ideas on how to clear the error?

[Ron_S]

Go online and then to diagnose

It should tell you there what the problem is.

[OG58]

15 minutes ago, Ron_S said:

Go online and then to diagnose

It should tell you there what the problem is.

Thank you Ron_S

Yes I have done that and the PLC says no errors? I am using GX Developer ver 8 something. I have looked through several manuals and tried resetting M9011 all to no avail.

 

 

[kaare_t]

Hi,

So the error LED is lit no matter what you do?? Sounds like a bad unit...  If the online diagnostics says "No Error", then the error LED should be dark.

[OG58]

On 10/21/2018 at 7:13 PM, kaare_t said:

Hi,

So the error LED is lit no matter what you do?? Sounds like a bad unit...  If the online diagnostics says "No Error", then the error LED should be dark.

Yes the unit may be faulty but apart from the output problem it works fine.

Ok I have been reading the manual and going through M points and D registers and can still find no indication of error. However the physical manifestation appeared last night and here is what happens.

I attempt to use logic to switch outputs on and everything  is fine until I try to exceed Y7. I can switch outputs Y10 to Y17 or Y20 to Y27 but only any given 8 outputs at one time.

Do you know the correct parameter settings for this model?

This is not my first time with a PLC I have a few of them and wrote my first PLC program in 1986 (Instruction code).

[Inntele]

If to say about error led, I'd check the battery status (M8005 and M8006 special merkers) and M8004/D8004.

[OG58]

2 hours ago, Inntele said:

If to say about error led, I'd check the battery status (M8005 and M8006 special merkers) and M8004/D8004.

Hi Inntele,

Thanks for your input, I checked those m contacts all zero and all registers read normal. I guess I will eventually find out the cause.

Reference Mitsubishi manual JY992D66301H  aka FX2 hardware manual.

[kaare_t]

23 hours ago, OG58 said:

I attempt to use logic to switch outputs on and everything  is fine until I try to exceed Y7. I can switch outputs Y10 to Y17 or Y20 to Y27 but only any given 8 outputs at one time.

So if I understand you correctly, you can switch on 0-7 OR 10-17 OR 20-27, but not several "batches" at once?

[OG58]

Hi Kaare_t, quote "So if I understand you correctly, you can switch on 0-7 OR 10-17 OR 20-27, but not several "batches" at once? "

Yes that is correct.

[kaare_t]

Well, what happens if you try to switch on Y0-Y7 plus Y10? Won't Y10 work, or does Y0-Y7 go dark?

[OG58]

Just now, kaare_t said:

Well, what happens if you try to switch on Y0-Y7 plus Y10? Won't Y10 work, or does Y0-Y7 go dark?

First in First works. If Y0-Y7 are on then Y10 or Y20 will not activate. Y0-Y7 stays on.

 

 

[Inntele]

54 minutes ago, OG58 said:

First in First works. If Y0-Y7 are on then Y10 or Y20 will not activate. Y0-Y7 stays on.

All it looks too strange, like a programming error. I'd recommend to clear (to erase) completely the PLC, then to test outputs manually by device test.
What software do you use for programming?

Edited October 24, 2018 by Inntele

[nehpets]

its been a while since I used a FX2N but I think the error led is actually two leds side by side if the righthand one is lit then its a program error, if both lit its a CPU error. Either way the special registers D8060 to D8069 should indicate an error code, with the corresponding M registers M8060 to M8069 set to indicate the D register.

To clear the PLC completely remove any memory cassette, remove the battery turn off the PLC and leave for 30 secs, Replace the battery, turn on the  PLC and switch to run.

As I said its been a long time .

Steve

 

[OG58]

On 3/6/2018 at 7:31 PM, nehpets said:

For goodness sake save yourself time and heartache and buy a lead at only $6.00 it's a no brainer.

SC-09 cable

 

Steve

I agree 100%, time is precious don't waste it.

[OG58]

I am giving up on the FX2N-48MT and accept it is faulty and will now concentrate on Mitsubishi A and Q series PLC.  Thanks for all your input  I learned some new stuff cheers.

[OG58]

On 10/24/2018 at 10:53 PM, Inntele said:

All it looks too strange, like a programming error. I'd recommend to clear (to erase) completely the PLC, then to test outputs manually by device test.
What software do you use for programming?

I am using GX developer Inntele. My personal thoughts are ROM bios image parameters changed or corrupted like memory error. I just wanted stepper motor control. So now I must go down the A or Q series path.

Edited December 15, 2018 by OG58
More information.

[Wasan]

@OG58 For clear memory in GX Developer. You should change switch from your PLC to stop then go to Online -> Clear PLC Memory. If Error still occurs. You should go to Diagnostics -> PLC Diagnostics and try to clear error if don't please capture error screen to us for check them.

[Inntele]

9 hours ago, OG58 said:

I am using GX developer Inntele. My personal thoughts are ROM bios image parameters changed or corrupted like memory error. I just wanted stepper motor control. So now I must go down the A or Q series path.

On 24.10.2018 at 5:53 PM, Inntele said:

All it looks too strange, like a programming error. I'd recommend to clear (to erase) completely the PLC, then to test outputs manually by device test.
What software do you use for programming?

Hi QG58,

I suppose the FX2N does not contain ROM bios, because on my opinion its processor & I/O controllers are implemented using FPGA/PLM technology.