Optipower BEC guard - do I need it for Kosmik?

[madeye]

I plan on using the Kosmik's BEC, and considering using Optipower Ultra Guard. One of configurations (OPRBG002 Combo) has the BEC guard component (see the link for the description).

Do I really need this for Kosmik? Statistically, how often, if at all, do things like the BEC guard is supposed to be protecting from, are happening?

[crash at 42]

http://www.demonaero.com/mobile/Prod...ode=R2-BUF-350
try this controls backfeed, powers electronics in emergency and no lipo maintenance

[Pitch-Itch]

I have one all my helis and all I use is Kon escs. Will I ever need it? I hope not. Will I be happy it is there if I ever do need it? Yep.

[DCflyer]

Originally Posted by madeye

I plan on using the Kosmik's BEC, and considering using Optipower Ultra Guard. One of configurations (OPRBG002 Combo) has the BEC guard component (see the link for the description).

Do I really need this for Kosmik? Statistically, how often, if at all, do things like the BEC guard is supposed to be protecting from, are happening?

Kontronik recommends you use the supplied fuse and some sort of backup power source depending on your servos. If using HV, you want a Lipo like the Optiguard. If using non-HV, a LiFe battery or 6v capacitor would work.

Do you need it to fly? no. But the the fuse and backup battery are designed to work together should something fail. If your ESC sustains a high current load for more than 2 seconds (that's what I've read), the fuse will blow, preventing any damage to the ESC/BEC/electronics etc. Your motor will then shut down - no ESC power. 0.5 seconds after all this happens your backup battery will pick up power to the servos and FBL to allow you to right the helicopter and bring it down safely. You will know this is happening because Optipower includes a VERY powerful flashing LED light that activates once the backup source is being used which is nice because it will give you precious seconds of headspeed to bring the heli down quickly.

I have the Optipower battery as well as two of their BEC guards I will be using on my 770/Kosmik 200 build. The more insurance the better.

[Pitch-Itch]

Originally Posted by DCflyer

Kontronik recommends you use the supplied fuse and some sort of backup power source depending on your servos. If using HV, you want a Lipo like the Optiguard. If using non-HV, a LiFe battery or 6v capacitor would work.

Do you need it to fly? no. But the the fuse and backup battery are designed to work together should something fail. If your ESC sustains a high current load for more than 2 seconds (that's what I've read), the fuse will blow, preventing any damage to the ESC/BEC/electronics etc. Your motor will then shut down - no ESC power. 0.5 seconds after all this happens your backup battery will pick up power to the servos and FBL to allow you to right the helicopter and bring it down safely. You will know this is happening because Optipower includes a VERY powerful flashing LED light that activates once the backup source is being used which is nice because it will give you precious seconds of headspeed to bring the heli down quickly.

I have the Optipower battery as well as two of their BEC guards I will be using on my 770/Kosmik 200 build. The more insurance the better.

You don't need an HV setup to use the optiguard.

It will always supply .5v less than what your BEC supplies.


Also I hope it takes longer than 2 seconds for the fuse to blow. I had a 430 amp spike this weekend on my mostro for a little over 1 second and my fuse didn't blow......yet.

[Wh1teAfr1can]

Originally Posted by Pitch-Itch

You don't need an HV setup to use the optiguard.

It will always supply .5v less than what your BEC supplies.


Also I hope it takes longer than 2 seconds for the fuse to blow. I had a 430 amp spike this weekend on my mostro for a little over 1 second and my fuse didn't blow......yet.

the fuse is based on these approximate values


(table credit to AndrewJHawes)
Time Characteristic
% of Amp Rating - Opening Time (Minimum / Maximum)
110% - (100 hrs / )
135% - (90 sec / 3600 sec)
200% - (3 sec / 100 sec)
350% - (0.3 sec / 3 sec)
600% - (0.1 sec / 1 sec)


so using the above table with a 200 amp fuse you have around 2.5 seconds at ~430 amps having a "spike" that lasts for more than 2 seconds is almost impossible.

[madeye]

Originally Posted by DCflyer

Kontronik recommends you use the supplied fuse and some sort of backup power source depending on your servos. If using HV, you want a Lipo like the Optiguard.

Let me clarify - I *am* planning to use the Optguard itself (and, of course, the LED), just wondering if I need the BEC guard. Specifically, the device that is the difference between these two configurations:

• Ultra Guard, 430 mAh LiPo, LED
• Ultra Guard, 430 mAh LiPo, LED, BEC Guard

[Pitch-Itch]

Originally Posted by Wh1teAfr1can

the fuse is based on these approximate values


(table credit to AndrewJHawes)
Time Characteristic
% of Amp Rating - Opening Time (Minimum / Maximum)
110% - (100 hrs / )
135% - (90 sec / 3600 sec)
200% - (3 sec / 100 sec)
350% - (0.3 sec / 3 sec)
600% - (0.1 sec / 1 sec)


so using the above table with a 200 amp fuse you have around 2.5 seconds at ~430 amps having a "spike" that lasts for more than 2 seconds is almost impossible.

Oh well I'm good then. I just assumed 430 would be on the bleeding edge of what the fuse can handle, but appears to be well within the limits. Cool, thanks.

[DCflyer]

Originally Posted by madeye

Let me clarify - I *am* planning to use the Optguard itself (and, of course, the LED), just wondering if I need the BEC guard. Specifically, the device that is the difference between these two configurations:

• Ultra Guard, 430 mAh LiPo, LED
• Ultra Guard, 430 mAh LiPo, LED, BEC Guard

Should have read more carefully I apologize. I'd be interested to hear a Kontronik rep give us the skinny on these as well. Its a brand new product and not really a lot of information out there right now on how they perform on K products.

People have been flying Kosmik's with backup batteries for a long time now without BEC guards with no issues. So I think you'd be fine without them.

I ordered a couple of opti's BEC guards and the one thing I notice right away is that the wire gauge that they plug in with into the FBL is of a smaller gauge than the Kosmik power leads. Will this create a bottleneck? Perhaps. If so, then the Opti backup guard might power on from time to time basically fixing a problem that was self-created to the BEC gaurds. These are the things i'm curious about. When I get around to building it and testing it i'll find out.

Hopefully someone else will get some answers up on this. Are there any opti reps on HF? I wish they'd chime in here from time to time. If someone knows of an opti rep could you please link them this thread?

[madeye]

...and there's another question I'm starting to ask myself while investigating buffer packs - if I have the Optipower UG installed, do I still need a buffer pack?

They work in a different way - to the best of my understanding, Optipower triggering *will* result in a voltage drop (effectively sending a jolt all the electronics will have to compensate for), whereas buffer pack won't cause it - but then again, it'll require dedicated hassle of properly charging it etc.

I'm sure I'm overcomplicating things, but well, y'all know the curse of the first build...

[dl7uae]

The drop is purposely (0.5V) to gain an alarm threshold.
The supplied electronics do not mind.

[madeye]

Originally Posted by dl7uae

The drop is purposely (0.5V) to gain an alarm threshold.

Yep, figured that by now, but thanks for reminding.

Originally Posted by dl7uae

The supplied electronics do not mind.

So do I need the buffer pack if the guard is installed?

...and the original question still stays.

[dl7uae]

So do I need the buffer pack if the guard is installed

"Normally" you don't.

You may experience a problem by the BEC powerup hardware design flaw. In most cases an Opti BEC Guard will cure it.
If not, a buffer pack w'd be the solution (bridging the voltage gap of the 1st second). ...but the UG is catching up, see below.

-----

In those cases (entire thread) a buffer pack helps more than an UG because the UG steps in in case of but at time of powerup it is not already present than just determining the nominal R/C voltage.

A different UG firmware version can turn UG's nature into a cross of a (not "dumb") battery and the well-known UG functionality. I think the (experimental) firmware has proven that it works (malc1 knows the details from practice) so we probably will spread it out in public (Opti will do then) for self-flashing by owners of "newer" UG's with an USB interface (easy: appears as a memory stick).

So in the end with an UG you potentially have also a buffer pack for the single moment a buffer pack can help better than an UG with the current functionality: at 1st seconds of powerup with the most sensible R/C device known: SPEKTRUM sat Rx.

The crux is resistance of servo connectors and wiring vs. dramatically rising servo peak current draw vs. increasing voltage sensibility of electronics and more and more ... electronics in the models. We cannot just provide another (better) connector system - so we already are on the actually wrong rail: We buffering voltage drops away instead of eliminating the causes.
Anyway. The main thing, it helps.

[dl7uae]

Oops, forgotten again..

...and the original question still stays.

Do I really need this for Kosmik? Statistically, how often, if at all, do things like the BEC guard is supposed to be protecting from, are happening?

... a fighter pilot: does he need an ejector seat?

Decide on the basis of its features:



If I say YES and nothing bad happens I owe you the price of a BG.

If I say NO and the worst happens - I owe you the value of a new heli.

[madeye]

Originally Posted by dl7uae

... a fighter pilot: does he need an ejector seat?

From my retired jet fighter pilot friend: unconditionally, yes. Related: http://roadrunnersinternationale.com...1_bailout.html

Originally Posted by dl7uae

Decide on the basis of its features:

(picture skipped) Makes a lot of sense, you got me sold on the idea. That's for R2 protector, though, how comparable is Optiguard BEC guard? I wish they provided a chart on par with yours.

Originally Posted by dl7uae

If I say YES and nothing bad happens I owe you the price of a BG.

If I say NO and the worst happens - I owe you the value of a new heli.

See that other message I sent

[dl7uae]

That's for R2 protector, though, how comparable is Optiguard BEC guard

Where's the difference?

Ok, clear question, direct answers (b4 heading to Zzzzz...):

- The KOSMIK BEC is not really a Ferrari but it is a well-powered Audi A6, - only.. with some blemish. Special is: The engine stutters when starting. JIVE Pro's BEC is the same but often misfiring after the start. Btw is the BEC controller in both the same as in the old JIVE.

- Back to KOSMIK: Until now, apparently, no case has become known that BEC's power FETs died and let the raw voltage through. Nevertheless, the chance that something like this can happen is always present. Disrupt the battery while motor current flows and zap.. overvoltage and perhaps killed power FETs of the BEC.

- The KOSMIK has (and I guess the KOSMIK only, not the JIVE Pro) something like an ideal diode between BEC output and output connectors. So far it is well-protected at this end. On the other hand EMF voltages can nevertheless disturb the voltage regulation because of some lack of appropriate capacitors. The BG cures that, makes a "healthier voltage".

- Buffer voltage: I'd say, yes, better to provide it. Three purposes:

-- Helps over the problematic time at motor starting. (pack or UG w/ our (still experimental) new firmware) -- Will I be faced now w/ the question of what R2 has to do with the UG?
-- Buffers every voltage drop by high current draw through too high contact/line resistance. Avoids resets or brownouts, deadly in case of a FBL which cannot calibrate in-air.
-- Allows safe landing in the worst case of emergency: BEC fails. This is actually unlikely in case of KOSMIK and from the previous statistics. ..but never say "never"..

[Over_Speed]

Tried to buy the R2, but they won't ship to Australia

[malc1]

I am setting up a new machine and the experimental firmware I now have on my Ultra Guard sorted out all my problems with flashing satellite receivers when my VBar was powered up.
Before this there was no way my system would work properly.There were loads of critical errors seen in the flight log.
Got the system working properly with my existing JR gear and then changed over to Jeti Duplex due the the telemetry that I required.

So I have an updated Ultra Guard and am also using a BEC guard on both of my Kosmik BEC outputs to be absolutely sure all is good.

[jmackey]

Originally Posted by madeye

From my retired jet fighter pilot friend: unconditionally, yes. Related: http://roadrunnersinternationale.com...1_bailout.html

Great read on Bill Weaver! Thanks for sharing.

[Wizza]

Originally Posted by Get2daChoppa

Tried to buy the R2, but they won't ship to Australia

Get2daChoppa, I buy my R2 buffers from microHELIS.de. They take Paypal and ship to Australia ok.... Very personalised service and emails to confirm your order and when shipped. They also sell the R board for the buffer, if your ESC can not take back power into the BEC.