Mitsubishi Melservo MR-J2S-100A alarm: AL.E9

[Per Hansson]

Hi, the ones I've seen have shown AL.E9 as first & only error AFAIK.
I work as a service technician, so I get called whenever the customers can't get the machines working again...
So far I've repaired quite a few of these and had 100% success so far, and no returns...
Actually I'm near Tampere sometimes for customers too (actually in Lempäälä) but not right now.

[sam_sam_sam]

Thank you for this posting I also repair servo drives I have had switching power supply problems from bad capacitor to bad switching regulator IC chips but have not yet seen this problem

Thanks again for sharing this post

[Leopard]

Originally Posted by Per Hansson

Hi, the ones I've seen have shown AL.E9 as first & only error AFAIK.
I work as a service technician, so I get called whenever the customers can't get the machines working again...
So far I've repaired quite a few of these and had 100% success so far, and no returns...
Actually I'm near Tampere sometimes for customers too (actually in Lempäälä) but not right now.

Thanks for the response. Nice to hear that the failure mode has been consistent.

We've luckily had spare units for the ones that have been acting up, but apparently this model is outdated and hard to get nowadays.

I'll order some optocouplers and will see if these can be brought back to life.

[sam_sam_sam]

When I have done these drive before I have given them a recap and change the switching regulator ic chip and now when I do another one of these drive I will change the optic sensor and the surface mount capacitor as well

After reading your post

[Alex-Signals]

hi, I made the change of the caps, and the HCPL7800A, in the DC BUS marks me an output of 280 vcd, the equipment was already installed in the machine and I am still working.
Since I don't have 33uf caps, install some 47uf caps. they believe that for this reason I am giving a bus voltage of 280 vcd, the caps I use are low ESR

[Per Hansson]

The bus voltage depends on the incoming AC voltage.
If you measure 200VAC input then 280VDC bus voltage is normal.
Calculation: √2 x 200VAC = 282.8VDC.

If not and you believe you have a heat sensitive component then heat it up with a heatgun carefully and see if the voltage changes.
Or cool it down and see if the voltage changes.
This is the way I used to pinpoint that it was component O15 the HCPL-7800 that was the culprit as described here.
And yes, the servo might be sensitive to the value of the capacitor, especially capacitor C6.

[jae2020]

Originally Posted by Per Hansson

Hi, these two caps came from a unit that otherwise is full of Nichicon caps:
Nichicon GQ, GU & PJ manufactured late 2001.
Got any idea what model they are? (See picture).

The 33µF cap has an ESR of 40 so it's in dire need of replacement
I could get it down to ca 5 by heating it with my iron, then matching the other cap...

Originally Posted by Per Hansson

I ordered the "A" version of the 7800 optocoupler linked above from Mouser, actually it was the only one in stock.
It worked a treat, the bus voltage reading is now correct

Thanks. I solved alarm E9 after replacing this IC.

[fazal kareem]

IF Driver Shows
AL.E9 change ic chip 7800 80% solved
AL.24 change module 50% solved
but
AL.30 ?
AL.17 ?

[bench22]

Thanks! also fixed my servo with alarm 9.

[macona]

I also had this same issue with my MR-J2S-100A on my cnc mill Y axis. Replaced that opto today and she is alive again. Thanks for posting all this!

[macona]

Oh, and I thought I should add it does seem temp related, it was not until the shop got cold that this issue cropped up.

[sam_sam_sam]

( these Servo drives are a pain in the ass to repair )

I have tried in the past to repair Servo drives that have a low buss voltage with limited success on some models it just replace all of the small value capacitor and that seems to fix the issue but not always the case

I have even replaced an IGBT module on one and never figured out what the problem was

With over current error message I have been more successful repairing this kind of fault

I have even repaired Servo drives that have priority controller boards this is even more channeling because if the controller board has issues it basically unrepairable but ( if the controller board still working) if you can find the same exact model then use the replacement drive with the original controller board and this dose work I have done this a few times before

[sam_sam_sam]

Originally Posted by macona

I also had this same issue with my MR-J2S-100A on my cnc mill Y axis. Replaced that opto today and she is alive again. Thanks for posting all this!

If this is a drive that is over 10 years old I would highly recommend that you recap the switching power supply board at a minimum and also recommend that any capacitor under 100uf replace them

[Per Hansson]

Nice to see so many new members in this thread, welcome to Badcaps!

On that theme I present you the latest repair:
I was hoping for it to be an "easy" fix but for the first time was greeted with leaking SMD capacitors in this servo!
The electrolyte had started attacking the through hole vias and crystalline formations had formed on the negative legs.
I used acetic acid and it worked a treat, I did not photograph the acids process in the first two caps but after what I saw was ready on the next couple.
I made this little GIF showing the action, the board turned out great after the cleanup thankfully!
P.S: I attached several high resolution photos of the before/after process as well, oh, and the SMD caps measured around 80 to 140 in ESR!

[ChaosLegionnaire]

nice... u used acetic acid? isnt that whats in vinegar?

[Per Hansson]

Exactly correct!
I even bought it at the local food market

[mohamed_bayoudh]

Hello

I have an MR-J2S-60A

I wired it by manual on 230v single phase,
it lights up fine, but it gives the error
Al E9 - "Main circuit de-energized warning"
I don't know where the alarm came from.

thanks in advance for all your help.

[Per Hansson]

Hello, please write in English as this is a English forum, SMDFlea translated the post for you this time.

You would begin by measuring the bus voltage on the main capacitors of the drive.
And then compare this to what the drive shows the bus voltage as itself via its internal status display "Pn"

[CBoulic]

hi all, i'm new on this forum , and i happy to read this post because I have the same issue with a Servo Amp mitsubishi MR-J2S-500B. i'm sorry for my bad english, please don't be angry!

I have 2 servo whit the same E9 one of two go to the repair society but they are not sure troublesoot it .
so i want try troubleshoot the second by my self!

m'y servo amp , show me an E9 and in the the datta sheet is :
AL.E9
Main circuit off warning Servo-on (SON) was switched on with main circuit power off.
Switch on main circuit power.
but this servo ( an 3 phases input) is powered . it smell the same error like you on your mr-j2S-100

on your precedent mesage you say read the bus voltage I suppose you talk about the DC rail after the PD3( 3 phases Graetz bridge).?
on this version of SAMP i' d'ont have button to enter the menu. and i d'ont have pilot systéme so is hard to make measurment.

with your experience, i found one opto 7800 but is not near the DC rail is on the smalest PCB but i can change it !

near the DC rail i found 0I12 , is an opto TLP621 and it's Diode is concted thougth the resistor to the DC rail i suspect a probleme with it.

on my PCB OI15 is not a 7800 is V454.

if your have idea i'm very interested about it!
thank you so much

[Per Hansson]

Welcome to Badcaps!
Your servo also has the LCD display, it is just in another location.
I attached photos of a 200A servo here, you can see the display behind the cover shows 322v.
This DC voltage you can measure between terminals P & N that I labeled in the photo, it should be similar in your servo.
(It is only the small servos (80A and below) that do not have one of these two terminals).
But in any case you can use cooling spray: so cool down the opto you suspect and watch the "Pn" voltage in the LCD display:
If you find the right optocoupler it will drop allot!
P.S: I attached the display flowchart!