Another attempt at fixing Apex EB832

[vetteguy53081]

Yea, I replaced the PSU with a new Mean well (with Harold’s adapter board). No visible damage.

If I leave the damaged outlets ON then I can notice sporadic relay clicks. Very sporadic.

If you hear clicking - good sign especially if you turn them on and off in Fusion. Also try going to tasks and do a software update on the EB832

 

[Rimsky]

I already did a firmware update to the EB832, no joy. The clicks happen randomly only if I leave the outlets ON.

 

[_AV]

Measure voltage at the 12v output when it hits the board out of your 12v PSU when you have all relays on. If it doesn't show a stable near 12v output, you might have messed up the traces replacing the PSU. I've repaired plenty of those as well.

 

[Rimsky]

I opened the EB832 again, cleaned it some more. After a while, I plugged it back and it seems to be working now. No idea of what was the issue but one thing for sure is that the unit had some humidity inside.

 

[Rimsky]

Now my next issue is this:

The EB832 I just bought shows a wrong voltage. The first one is my old/good EB832 showing the correct house voltage. It was also showing wattage even when nothing was plugged. I ran the eb8zero 3 command and that fixed the wattage but not the voltage.

Any suggestions?

 

[_AV]

The unit has bigger problems unfortunately. I'll bet that the eb8zero didn't actually fix the wattage issue, but rather covered it up. If you were to plug in a device with a known wattage consumption, it is likely that the reading will be wrong as well.

 

[Rimsky]

The voltage is slowly going down. We will see what happens after a few hours.

 

[Rimsky]

I suck at this. From half of the outlets working then all outlets working intermittently and reporting wrong voltage. I then opened it to check it again and now I have no outlets working (except the 24dc, which always work).

The only thing that I notice is that the buck converter U13 gets very hot. I had new ones of those, so I replaced it, did not fix the issue, the new one also gets very hot.

Believe me, if I were in the US I would send the unit to @_AV , but I'm not and it is cost prohibitive. I guess I learned a lesson about not buying used stuff, it was obviously humid/salty inside. I don't think that the seller know about the issue, but probably storing it with salty water inside damaged something as time passed.

What a bummer. If there is any idea of what to check or things to try, please let me know. I have another (broken) EB832 on hand that I can swap some parts.

 

[_AV]

You must have a short somewhere down from U13. Perhaps U1 or the can trans or the main controller. U13 always gets really hot under load. There is clearly a load somewhere and it's not a good one.

 

[Rimsky]

You must have a short somewhere down from U13. Perhaps U1 or the can trans or the main controller. U13 always gets really hot under load. There is clearly a load somewhere and it's not a good one.

Well, there is the load of the Apex Head Unit.

 

[CaptainOver]

After 3 failed EB832 (2 successfully fixed with help here), my Trident has decided to join the fun. In this case, the pump seems to work fine, but none of the solenoids are firing. Anyone know where to check/look on the PCB to see if it is something obvious?

 

[minus9]

@gveng here's the repair guru for the EB832.

 

[gveng]

@gveng here's the repair guru for the EB832.

Thanks John! Sending him a message now.

 

[A.Jones]

Oh! I could use an EB832 guru! @gveng or anyone else with great ideas I'd greatly appreciate some advice. My EB832 failed in the usual way. I replaced the 12V PSU, great now there's power but that unearthed another issue, so I replaced the CAN transceiver, now everything seems to be working properly...except the fan.
I bought a replacement 5V fan but it just twitched and squealed so I checked the voltage. I'm getting a constant 12VDC instead of 5V. So I figured engh, fan constantly on, not a bad fail state, I'll just get a 12V fan. Ordered one, hooked it up and it works but I compared the airflow to a newer EB832 that has never failed and that one puts out noticeably more airflow (which is saying something since these aren't exactly high airflow fans) so my half butt solution probably isn't a good one. For reference, the old semi-repaired fan contacts put out (according to my multimeter) 11V 16mA and the newer never failed EB832 puts out 4V 21mA.
Anyone have any recommendations? Things I can test? Things I can try replacing?
Having opened up the unit, ordered the 12V PSU, then ordered the CAN, then the fan, this EB832 has been sitting open in a common area of my house far too long relative to my wife's tolerance of my tinkering.
THANK YOU!

 

[REEF_TO_KEEP]

Some of my previous repairs:

Radion XR30 complete no light repair

My previous electronic equipment repairs Radion XR15: https://www.reef2reef.com/threads/radion-lights-board-level-repair.774331/#post-8197536 A fellow reefer mailed me their Ecotech Radion for repair service as it's long been out of warranty. The unit turns on briefly before shutting down and...

www.reef2reef.com

Radion Lights Board Level Repair

I enjoy an occasional board level repair. It gives me a new angle to this hobby, which is often very heavy on DIY. In this thread I'm going to post some of my more interesting and challenging repairs, picture heavy, including high magnification microscope imagery. Recently, I got ahold of a...

www.reef2reef.com

AI Hydra Fan Connector Repair - Significant Corrosion

My previous electronic equipment repair projects Radion XR15: https://www.reef2reef.com/threads/radion-lights-board-level-repair.774331/ Radion XR30: https://www.reef2reef.com/threads/radion-xr30-complete-no-light-repair.792711/ Imagine a problem with a connector breaking off the board...

www.reef2reef.com

First off, let me give a lot of credit to @MadeForThat for bringing this issue up in his excellent post earlier:

Fixing an EB832 with non-functional outlets but does have functional indicator lights

CAUTION- I am not liable for any damages to your person or property. This is offered as a possible solution to an electrical problem, and with this territory comes risk to your health and property that may not be directly mentioned. You should only attempt this repair if you are sure of your own...

www.reef2reef.com

I think that a lot of people can benefit from this type of information.

I've also been wanting to write about this for sometime. Was just looking for a good opportunity. Alas, I didn't have to wait too long: I received a broken EB832 from a fellow reefer for repair and before opening the unit, I already new exactly what the problem is going to be.
But just knowing is not going to do this poor EB832 any good, we need to get it working again. So let's open it up. Notice that this particular EB832 is very very clean. There is no salt, oxidation or anything inside or outside that would suggest that the failure is due to negligence. So what is wrong then?

Oh, look! There it is, like that shy girl at a prom dance, sitting in the corner, wondering if anyone will notice her:

Yes, this is our little 12V AC to DC power supply. model YS-5V1ASZD. Its only purpose in life is to provide power to a couple of controllers so that the EB832 can communicate with Apex head unit over aquabus. Well, that and also so that it can switch outlets on and off. Both tasks are kind of critical to the proper operation of the entire unit.

Like oxygen to a brain.

So just like that shy prom girl, our little PSU has a big heart filled with the motivation to do the best it can to make this humongous unit a better place, by providing power to critical components. But it doesn't know yet that it really can't do that. Or it really shouldn't be forced into this situation. Why? Let's take a closer look at the PSU:


From the markings, we would assume that it is a 5V 1A power supply, but it is not. It is a 12V PSU, 500mA. Should be plenty big to empower those ICs. The design is very common, I believe this particular one is open sourced and widely available. On the board we see all kinds of prefilters, coils, capacitors. So why can't it do what it was designed for? Let's take a slightly different angle:



First, can you see a somewhat bulged capacitor on the left? This is where it all starts. @MadeForThat saw that too I'm sure, but he didn't want to rant in his post. So you get to read my rant:

<RANT>
Capacitors fail often. They are both very critical and yet represent the most common failure in power supplies. But not all capacitors are the same. Every device with electronics needs a PSU, yet not every device fails due to a PSU in the first 2 years of operation. This suggests that some that don't fail as often use capacitors that are somehow different, I would event go on a limb and say that they might be, oh, I don't know, of a higher quality. That way they last longer and work better. Let's take a look at what Neptune chose for their EB832:

Zhuohao capacitors? Zhuohao are not just low quality, they are the bottom of the bottom of the barrel capacitors. You can pretty much only source them directly from China. No reputable electronics supplier in the US carries them. Just google them to get some juicy details from the electronics community.
As it was previously mentioned, this entire PSU assembly, including capacitors and whatnot, can be purchased retail at ~$3-4. Shipped.
These particular PSU are really hobby grade items. If you are into Arduino tinkering, then it's a good option to prototype a toy project.

Neptune didn't even implement this module, they bought a truck load of them on alibaba. Because they are probably $1 or less each wholesale.

<END OF RANT>

Enough ranting. This poor EB832 is still hurting and needs to be fixed.
Of course, there is always an option to just replace the failed PSU with a working one. But the problem is that we would be replacing one subpar component with another component which is equally subpar. What if we fixed the component by replacing very low quality parts with something that is going to actually last past Neptune's meager 1 year warranty?
After all, the design of the PSU is very common and actually good enough for what it must do. It's the choice of parts to implement it that is questionable.

To verify the theory that this PSU is our problem, we will perform a quick diagnostic. The PSU is rated up to 1A current. It also has a red LED on the DC side to indicate that it's working properly. Just because this LED is on, doesn't mean that the unit is working to the specs. We'll apply a reasonable load, a small computer fan with 0.25A draw to the DC side to see if the PSU can power it up. In my experiment, the fan didn't spin and the red LED immediately turned off under the load. Capacitors are bad.


To fix this, we will remove all capacitors on board, regardless of their condition. We don't want that junk, as we can never be sure how much longer they will last. All caps removed and the area is clean and ready for the good stuff:

And speaking of the good stuff. For the fix, we have a healthy mix of brand new Panasonic, Rubycon and Nichicon capacitors. All top brands with longest life available:

These capacitors together probably cost more than the entire PSU unit they are going into.

They fit nice and clean into the original spots on the board:


Let's clip excess leads and the module is all back together and ready to go:


I tested it with the same 0.25A fan and now the fan spins and the red LED stays on. The PSU is now fixed.

Once it's back inside the EB832, the red LED stays on and the EB832 is happy again.

Thank you for very good information.

My EB832 acted up last night. After I turned off the return pump (cor 15) and waves for water change, Apex showed modules (just these guys) missing after I turned it on. I unplugged the power of cord the EB832 and plugged back in nothing works. I can hear the relay clicked and statue LED turned and off again. This happened every 4 seconds (relay and light) and it continued. Could you please let me know the 12V PSU gone bad.

Thanks for you help

 

[_AV]

Quite possible. What gives me pause however is that you have modules gone missing, which is not the typical symptoms of a failed 12v PSU.

 

[jjam]

Has anyone had the aquabus voltage at 2.8v? The 24v power supply is good and the meanwell 12v is good. When I plug it in there is no logo light and I think it is the 2 relays by the 24v that are going nuts.

No shorts anywhere around u13 that i can find. I thought about just ordering a u13 replacement but was wondering if there is a way to check it.

 

[jjam]

just figured I would update this.

R19 was bad. replaced it and all is good.

 

[2mk]

just figured I would update this.

R19 was bad. replaced it and all is good.

how do you repair these tiny chips? where are you getting them from? I don't have issues yet with these "control board" transistors yet. Can you collaborate how you check these are bad or not? I am interested to learn in case it happens to me.