Cap banks - the pre-emptive answer

[drwayne]

Thanks Ray.
I apologize if my spiel was over the top .. the benefits can be lost if detail ignored, IME.
Yes, the 5xcap ETTI bank ( here at OSE) is parallel. Ideal for any application. If you have a high rpm ( +45k rpm) and/or use a high demand motor, the parallel cap banks are limited in energy turnaround ( still charging when esc demands more.. )
All this being said, many people have successfully run sets without the circuit in this post..
Flashbulb circuits are similar the established circuit for cap banks.. FLASH, then recharge... FLASH, then recharge.FLASH, recharge, and so on ..
The circuit detailed above would deliver a smaller Flash, but allows more frequent releases ( 8 fold ) equating a nett higher turnaround per second.

Ive been archived ? . wow, now Im preserved for eternity !

regs
W

Holy Cow! I didn't think it was that complicated!
YOu oviously make good sense from what I read.

I would guess the Etti cap bank is all parellel ? Since only 5 caps...?

Copy & paste in archives...

Thank you!

[maxmekker]

Hello . This is starting to be beyond me technically at this point. I just want to ask a few quick questions from the start of the post. I’ll Try to keep it short
I wonder , how will a ESC performe if the caps are getting bad ?

I’m asking since My T180 ( 2+ years) is feeling a bit strange, like it's not 'opening up' I hit 100% throttle, and it feels like just 75% if you get me. (and yes I have re prog. It)
The caps looks fine, no bulging ore leak’s, but last year I did some 5s runs with my leo 4074 2000kv and the caps got really hot(x442 prop 45-90c lipos) so I thought about a cap bank, but never got around to get one before end of sess. Last year ( I did only a few packs of 5s, running on 4s most) . Well I have one now, the one ( ose cap bank) mentioned by tlandauer.

Anyway, the strange feel of the ESC I talked about came after I did some run with a new 4074 2150kv + 65-130c Lipo’s This year . I got some heat problem to (desolder of the + wire towards the ECS on the serial cabel 3 times)only with the 65-130c. But the heat on the caps/ecs motor were all fine.
But I thought about last years’s 5s runs and thought maybe the caps are saying goodbye.

If I boil it down the this:
How should I know if the caps are getting bad, and how should I hook up the ose cap bank , when stated in the first post not remove the existing cap’s. Did you get around doing you’re yet Tlandauer.

Thanks

[KartRacer]

Oh I get it. LOL. Not really or even maybe, but still very interesting reading. Thanks to all of the highly knowledgeable members on these threads. It DOES help!

[tlandauer]

Hello . This is starting to be beyond me technically at this point. I just want to ask a few quick questions from the start of the post. I’ll Try to keep it short
I wonder , how will a ESC performe if the caps are getting bad ?

I’m asking since My T180 ( 2+ years) is feeling a bit strange, like it's not 'opening up' I hit 100% throttle, and it feels like just 75% if you get me. (and yes I have re prog. It)
The caps looks fine, no bulging ore leak’s, but last year I did some 5s runs with my leo 4074 2000kv and the caps got really hot(x442 prop 45-90c lipos) so I thought about a cap bank, but never got around to get one before end of sess. Last year ( I did only a few packs of 5s, running on 4s most) . Well I have one now, the one ( ose cap bank) mentioned by tlandauer.

Anyway, the strange feel of the ESC I talked about came after I did some run with a new 4074 2150kv + 65-130c Lipo’s This year . I got some heat problem to (desolder of the + wire towards the ECS on the serial cabel 3 times)only with the 65-130c. But the heat on the caps/ecs motor were all fine.
But I thought about last years’s 5s runs and thought maybe the caps are saying goodbye.

If I boil it down the this:
How should I know if the caps are getting bad, and how should I hook up the ose cap bank , when stated in the first post not remove the existing cap’s. Did you get around doing you’re yet Tlandauer.

Thanks

In my case my caps were swelling, I knew it was time for me to replace the stock ones which was just what I did, the same found here: http://www.offshoreelectrics.com/pro...v-1000&cat=123
I took them out, my thread is found here : http://forums.offshoreelectrics.com/...C-CAPS-bulging!
I wanted to add a bank however, so I asked drwayne all those questions. Much to my regret, I don't have any room to attach the bank on the power wires, so I did what I could, it looks like your pictures. I must say for me to use this bank is over kill since my application is for 4s set up only. If I could fabricate a bank myself I would use the replacement caps, they are smaller. Here is a picture of what I did:001Cap Bank for Seaking 180.jpg
I think anytime you suspect the caps are not up to their job, replacing them is never a bad idea. However, while the bulged caps were still on the ESC, I did not see any degrading in performance, but swelling caps are time bombs so I replaced them immediately. I am not knowledgeable enough to tell you what if anything is wrong with your ESC, but if the caps are visually good, maybe something else needs to be considered.
By the way, if original caps are not in top shape, they NEED to be replaced, adding a bank over half-dead original ones is not a sound solution. What drwayne said was the seller removed ALL the original ones and just added a bank, if I understood correctly.

[ray schrauwen]

It has been a thought of mine for some time that why mosty Suppo esc's burn up is most likely due to faulty caps they buy in massive quantities not caring if they are way out of spec or just not made right at all. I mean, the fets on Suppos are a discontinued fet in USA that was shipped in container loads to China like many other obsoulete electronic components.

A while back I grabbed a near new HK SS100 esc and the cap wires nearly fell off from inside the caps?? I replaced the caps with blue 1000uF 35V-130* Rubycon RX30's right onto the board. It works very well now.

I remember Etti used to use the Suppo base board BUT, they used the blue Rubycon's instead.... wonder why.

[drwayne]

Hello . This is starting to be beyond me technically at this point. I just want to ask a few quick questions from the start of the post. I’ll Try to keep it short
I wonder , how will a ESC performe if the caps are getting bad ?

I’m asking since My T180 ( 2+ years) is feeling a bit strange, like it's not 'opening up' I hit 100% throttle, and it feels like just 75% if you get me. (and yes I have re prog. It)
The caps looks fine, no bulging ore leak’s, but last year I did some 5s runs with my leo 4074 2000kv and the caps got really hot(x442 prop 45-90c lipos) so I thought about a cap bank, but never got around to get one before end of sess. Last year ( I did only a few packs of 5s, running on 4s most) . Well I have one now, the one ( ose cap bank) mentioned by tlandauer.

Anyway, the strange feel of the ESC I talked about came after I did some run with a new 4074 2150kv + 65-130c Lipo’s This year . I got some heat problem to (desolder of the + wire towards the ECS on the serial cabel 3 times)only with the 65-130c. But the heat on the caps/ecs motor were all fine.
But I thought about last years’s 5s runs and thought maybe the caps are saying goodbye.

If I boil it down the this:
How should I know if the caps are getting bad, and how should I hook up the ose cap bank , when stated in the first post not remove the existing cap’s. Did you get around doing you’re yet Tlandauer.

Thanks

1. remove and replace all the onboard caps.
2. or, you can remove those onboard caps without replace, providing you add extra close by
3. Bad caps cause major draw from batteries = heat = melting things..
4. slow performance likely due those ld caps having a draw demand on batts, not feeding so much to esc.
5. caps do have a limited lifespan in high yield applications.. overheating them is terminal.

W.

[drwayne]

It has been a thought of mine for some time that why mosty Suppo esc's burn up is most likely due to faulty caps they buy in massive quantities not caring if they are way out of spec or just not made right at all. I mean, the fets on Suppos are a discontinued fet in USA that was shipped in container loads to China like many other obsoulete electronic components.

A while back I grabbed a near new HK SS100 esc and the cap wires nearly fell off from inside the caps?? I replaced the caps with blue 1000uF 35V-130* Rubycon RX30's right onto the board. It works very well now.

I remember Etti used to use the Suppo base board BUT, they used the blue Rubycon's instead.... wonder why.

+1
ditto CC240LV 3+ years back... use to burn cap leads ... 4S 1515/1Y - pop .. changed to upmarket caps.. 6S1527/1.5Y
around then decided to design own esc.... never looked back
W

[maxmekker]

Dr wayne and T landauer( do I see a Geico ? :-) ), thanks for the info.

I took out the t180 just now and snapped a few photos. Don't know if they have leaked ore if it's just becuase I did a poor job of drying it properly after I had a leak in the boat , but I will replace them.
So, just to make sure. Remove the 3 stock ones all together, and just solder the cap plate directly onto the T180, ore do I make a small gap with 8-10-12 G wires ?

I wonder if this will help on speed. It's like the boat have had a small amount of brake on the last times I have been out. I eveen felt slower with the 2150kv compared to the 2000kv I had in it before. Not that it has anything to do with caps (maybe) but here is a video of a pnp mystic I have set up for a friend, and my geico . We both run ose flex, T180 esc 45-90c lipo 642 prop and and the hull is the same so they should performe likewise. but the mystic smoked me. At firts he not floring it so be patient :-)

[tlandauer]

You should first remove the old ones and solder replacement ones into the old holes so to speak. Take a look at the polarity before you do this, the trick is to have a helper firmly hold your ESC because you need to pull those with one hand while the other still holding the solder iron tip to heat the cap wires. On each of the cap I pull on polarity wire at a time, ---Don't over heat electronics. ( realistically you can't heat both + & - at the same time. yes, there is some twisting and yanking).
I shortened my Batt. to ESC wires prior to attaching the Cap Bank, therefore I deprived myself the chance of having enough wire INFRONT OF the ESC for directly mounting the Cap Bank. The hull of the Geico, yes it is MG!! is too shallow. I then had to add short pieces of wires between the Cap Bank and the ESC. Solder the wires under the main posts of the ESC---scrape the factory coating off first or you will have a hard time for the new solder to form a good contact.
Your third picture is exactly what I did, bridging the two with short 14g wires. But, if you can attach the Cap Bank on the main wires as drwayne recommands, it will be more efficient.
I used 14g wire only because I did not want to over heat the underside of the ESC main terminal, larger gauge wire is better, but if you look at the T-180 V3, their factory Cap bank is attached with very THIN wire, therefore I think 14g is enough.

[maxmekker]

I'll be on it soon, thanks. Pic's later.

[properchopper]

What's the Bottom Line ?

Amigo's,

I appreciate all the info and discussion on this important subject, but frankly I'm somewhat embarrased to admit that I can't readily distill the information offered into a simple, practical application realm. Is there a formula or application chart that would summarize how to choose/add capacitors for any given application given parameters that include battery voltage, esc capacity, motor pole/rpm considerations ? This might have been discussed before, but here might be a good time for a refesher course. In my honor it could be called "Capacitor Education for Electrically Challanged Dummies"

[tlandauer]

I don't think your slowing down has anything to do with the caps. Internal resistance as the contact gets unsoldered? Anyway, good video, enjoyed watching it. Also I realized you are an soldering expert so please do not take my long winded too seriously!

[maxmekker]

Well I have made a tread about the unsoldering stuff, and got so my ears hung down for my poor a.. soldering job. I have been soldering for ages, some 200 playstation chips, loads of para/serial connections, lipo packs etc for my boat's and flying buddy's, but all of a sudden my serial cabel wich I had used for a long time came unsoldered. Then I made another one with higher G wire, all fine on 45-90c lipo, and then on 65-130c unsolder again, and the boat feels slow so I'm willing to try everything to see if it helps.

[maxmekker]

Anybody care to tell me what these little buggers do. One of them was 'eaten' on a bit, and was loose. No way I'm getting it to stick to the board again. So is it a rip on this 180 ?

[millzee]

I'm sure it'll be fine doc, As discussed on the phone, this speedo being made an example of had two caps that swelled a little on my very first day driving an fe boat. The DF35 (bomber boat) was my first boat, first build and first time driving a fe boat and as seen on the video made of my first ever run, the flex shaft was offline a tad causing vibrations and rubbing, add to the fact I'd never heard one of these boats so I didn't know the difference and drove it till the shaft went BANG. After retreiving the boat I took more video footage of the esc and caps and on advice removed the caps from the board and replaced them with the etti cap bank. This speedo has been this way for every run and video made of my df35, being my first boat and trying to learn how to trim, I had someone take video footage everytime I ran the boat, here's the Running history of the esc
first run: http://www.youtube.com/watch?v=tK0ITqCORmQ
2nd test: http://www.youtube.com/watch?v=6C-o7MV5Ifk

http://www.youtube.com/watch?v=yfVDJW6UXCs

http://www.youtube.com/watch?v=fA2uhwQpjzI

http://www.youtube.com/watch?v=U_hjJX8lqZM

http://www.youtube.com/watch?v=k3vG0-_GcqA

http://www.youtube.com/watch?v=nNXsKogxces

The boat was stripped down and became the bomber boat and never driven again due to the expensive graffiti put on the boat on Febuary 6th. I pulled the electronics back out and put the boat in a custom glass/mirror case, this being said, I'm sure the speedo is fine.