Scorpion Backup Guard

[T-CAT]

T-cat..........Thanx for the clarification. I too remember Alpha's post about the 6V threshold.
With that being said, a BEC will not surge upward a half volt but it can and certainly does sag lower under stressing system demands.
So going back to your statement of going to a programmable ESC that you set the BEC to 5.5v, there is plenty of margin to the top end suggested limit.
If folks are looking for a electronic insurance device the BUG is a very viable solution when used in addition with the likes of the ZTW 6A/10max UBEC.
https://www.motionrc.com/collections...w-10a-bec-ubec
This also has a better amp output than the stock UBEC provided on the FW 1700 A-10;)
For those with the A-10 a really killer deal for $7 more than the above is the 15A dual input.
https://www.motionrc.com/collections...c-ztw300700010
No worry now for supplying all the amps the system needs and this is an ideal solution to having both LiPo sources(like on the A-10) powering the UBEC.
The stock method has only one of the two batteries powering the system.
What happens if that particular battery goes flat before the other?:Scared: With the dual input UBEC you only loose one motor and have half a chance to getting back safely.
If both batteries go flat(cause ya pushed the time or whatever) this is where the BUG does it's job for a dead stick.
More tech food for thought but put in a practical application perspective:Cool:
Best regards,

No problem at all, and I appreciate your input and perspective as well.

One goal of bringing up the voltage conversation regarding the BUG activation is that the stock BEC on some equipment including the Freewing 1700mm A-10 PNP jet is set for 5V. Since the manual that comes with the BUG states that it will activate at 5V and lower, the stock BEC may (and likely) not be sufficient to use with the BUG. If a voltage drop is seen during times of dropping down the gear with full flap input simultaneously, etc., the BUG may activate too often since the BEC voltage and BUG activation are too close. That's why going with a different external BEC that can be adjusted to a higher voltage than the BUG activates, such as the voltage you stated as example (5.5V), may be a more consistent and safer bet to keep the BUG from being activated when a person doesn't want it to be. As long as the voltage chosen for the external BEC is still safe for the rest of the electronics in the chain, it should be good to go.

[Ironfrog25]

Hi I just used the scorpion back-up guard in my Freewing A-10 80mm and noticed that it was very warm after I landed. I was wondering since to voltage from the BEC and Scorpion are so close if it is safe to have both plugged into the receiver? I am worried about sending to much voltage to the servos.

[xviper]

Hi I just used the scorpion back-up guard in my Freewing A-10 80mm and noticed that it was very warm after I landed. I was wondering since to voltage from the BEC and Scorpion are so close if it is safe to have both plugged into the receiver? I am worried about sending to much voltage to the servos.

The Back Up guard does nothing unless the voltage in the RX drops below a pre-determined level. If all is well, the Scorpion just sits there. The heat from it is likely due to the the little red light that's on when it's on "standby". Any other heat will be from the ambient temp of the compartment where you have it. Besides, even if it was providing volts all the time, it's hooked up in parallel so it can't add more volts as if it were hooked up in series. But that's not how it works.

[Ironfrog25]

Thanks for your reply xviper. I checked the back-up guard with my balancer after that flight and it was being used during the flight it had 85% when I checked it with my balancer/tester.

[OV10]

No problem at all, and I appreciate your input and perspective as well.

One goal of bringing up the voltage conversation regarding the BUG activation is that the stock BEC on some equipment including the Freewing 1700mm A-10 PNP jet is set for 5V. Since the manual that comes with the BUG states that it will activate at 5V and lower, the stock BEC may (and likely) not be sufficient to use with the BUG. If a voltage drop is seen during times of dropping down the gear with full flap input simultaneously, etc., the BUG may activate too often since the BEC voltage and BUG activation are too close. That's why going with a different external BEC that can be adjusted to a higher voltage than the BUG activates, such as the voltage you stated as example (5.5V), may be a more consistent and safer bet to keep the BUG from being activated when a person doesn't want it to be. As long as the voltage chosen for the external BEC is still safe for the rest of the electronics in the chain, it should be good to go.

Your absolutely spot on. Using the BUG with the "stock A-10" UBEC is not a viable voltage backup source.
I learned that on the maiden flight of the A-10 and found that the Scorpion had been initiated due to a system voltage drop most likely caused during the retract process and found that it continuously occurred with every flight afterwards until swapping in the ZTW where it was set to the 5.5v as indicated in my earlier post.

[xviper]

Thanks for your reply xviper. I checked the back-up guard with my balancer after that flight and it was being used during the flight it had 85% when I checked it with my balancer/tester.

I don't think that means it was being used. That LED light can easily burn up 10+% on a typical 5 minute flight. To test it, just turn it on without it being plugged into anything. Leave it for the same amount of time your flight is and see how much it depletes.

[Porkster]

Your absolutely spot on. Using the BUG with the "stock A-10" UBEC is not a viable voltage backup source.
I learned that on the maiden flight of the A-10 and found that the Scorpion had been initiated due to a system voltage drop most likely caused during the retract process and found that it continuously occurred with every flight afterwards until swapping in the ZTW where it was set to the 5.5v as indicated in my earlier post.

Mine will not activate unles I jam the retracts in which case it activates then switches back to normal once the system recovers and the motors powering the gear shut off.

[OV10]

Mine will not activate unles I jam the retracts in which case it activates then switches back to normal once the system recovers and the motors powering the gear shut off.

Am rather confident that you must be using another device other than the Scorpion.
The Scorpion sits in a monitoring mode of the system voltage until it falls below the turn on set point of +5vdc and then turns on providing +5vdc to the system.
Once it turns on it does not reset back to the monitoring state of the system and continues to stay powered on even if the system goes back above the set point level of 5vdc.
This can be a trepidus situation if the BEC's switching circuitry doesn't play well with parallel voltage sources.

[Porkster]

Apologies, you're quite right, mines a optipower BUG.

[quitcherbitchen]

Nice discussion. I have been playing with the idea of getting a bug since my FMS Mustang browned out. It survived to fly another day, but it was a major wake up call. I have since jacked up the CC10 bec to 5.5 volts and that seemed to solve the problem. 5.1v is CC default. I haven't had more then 6 flights since though. The digital FMS servos seemed to freeze first during the major sag that I had experienced. That being the elevator. I pulled out of a near vertical dive to crash land in the only patch of grass for a 100 yards. I never knew about the Opti. I too would like to know of a US distributor. I think for me the amount of time spent customizing the paint and other things makes the insurance seem more worth while. Some of my planes started off inexpensive, but after hours of prep are now hard to replace. It is hard to build up the momentum to do a do over sometimes.

[xviper]

If I understand the meaning of "brown out" (RX losing communication with TX), a "BUG" won't help here. A BUG only provides power to the RX if the main source of power is interrupted. It won't help re-establish communication with the TX. You need a better antenna system for that.

[quitcherbitchen]

I have a Hitec A9 radio that uses an SPC cable that is suppose to prevent or at least speed up reboots. What SPC doesn't do is help with Servo Brown OUT!!! I think the solution is one of these Bugs or Opti. My UBEC was obviously overwhelmed by a loss in battery power during a sag. The receiver browns out at 3.3 volts but my telemetry record showed that the planes lowest voltage was 4.8v. I now respect digital servos hunger for volts.

[Legman01]

I used the Scorpion Backup Guard in my FW A10 today for the first time. After a 2:30 flight, the BUG and BEC were both very hot! The BUG battery cells went from 4.2v down to 3.8v on this flight, so I figure it must have been activated since gear retraction or earlier. Without the BUG in use, the A10 BEC just gets warm, not hot.

Tried the BUG in another plane (xtreme Flight extra 300 on 4S) and it stayed cool the whole time.

Thinking I'll discontinue use use of the BUG in my Hog and look for a better "insurance" option!

[OV10]

I used the Scorpion Backup Guard in my FW A10 today for the first time. After a 2:30 flight, the BUG and BEC were both very hot! The BUG battery cells went from 4.2v down to 3.8v on this flight, so I figure it must have been activated since gear retraction or earlier. Without the BUG in use, the A10 BEC just gets warm, not hot.

Tried the BUG in another plane (xtreme Flight extra 300 on 4S) and it stayed cool the whole time.

Thinking I'll discontinue use use of the BUG in my Hog and look for a better "insurance" option!

Hello Legman,
The BUG was kickin on because the Hogs stock UBEC is only a 5v output and the turn-on threshold of the BUG is set for the same level so it was doing it's job basically the instant you turned it on and was fighting with the stock UBEC for voltage control(That's what switching BEC's do).
The BUG is a great insurance option if you use a BEC that has a higher voltage output like 5.5v or 6v.
I'm using the ZTW 10A UBEC on my Warty and several other birds that have the BUG in use on them.
https://www.motionrc.com/collections...w-10a-bec-ubec
I set the voltage output jumper to 5.5v on the ZTW and the BUG stays deactivated until the system voltage truely collapses to/below the 5v threshold the BUG was designed for.
Hope this info helps guide all those inquiring minds.;)

Best regards,

[Bandiferous93]

Another thing that worries me a bit is that the Scorpion Back Up Guard is supposed to activate when it detects the receiver voltage dropping below 5V. However, if we look at this from a PNP Jet standpoint and many other PNP airplanes these days, the BEC voltage is set to 4.8V or 5V. I usually see 4.8V though, and if the BUG is supposed to turn on at 5V, it would turn on right away since the BEC voltage is lower than the activation voltage of the BUG. The electronics in these PNP jets like the servos, retracts, lights, etc., are best used at no more than 5V. If we used a different BEC and set the voltage to 5.5V or something similar just so the BUG doesn't detect low voltage and activate, we are risking the life of the stock electronics.

Food for thought/discussion...

That's a big advantage of the Optipower Ultraguard 430. It detects system voltage automatically on on every power-up and sets its "trigger" point 0.5V below that, so it dynamically moves up/down if BEC system voltage ever gets changed. I run a couple on large helis and have never had a problem with them. I use the LED modules so I'll get bright flashing lights if the UG ever kicks in. Other than remembering to unplug the battery if you aren't going to fly that model for a while, it's about as fire and forget as can be. It stays charged/topped off from the flight pack and automatically turns on when it detects a flight pack plugged in so you'll never take off with dead weight as you might with the Scorpion BUG that has to be switched on/off manually.

[T-CAT]

That's a big advantage of the Optipower Ultraguard 430. It detects system voltage automatically on on every power-up and sets its "trigger" point 0.5V below that, so it dynamically moves up/down if BEC system voltage ever gets changed. I run a couple on large helis and have never had a problem with them. I use the LED modules so I'll get bright flashing lights if the UG ever kicks in. Other than remembering to unplug the battery if you aren't going to fly that model for a while, it's about as fire and forget as can be. It stays charged/topped off from the flight pack and automatically turns on when it detects a flight pack plugged in so you'll never take off with dead weight as you might with the Scorpion BUG that has to be switched on/off manually.

I agree, it’s a big step up and a very nice unit.

[quitcherbitchen]

Is the BEC guard any good?

[Bandiferous93]

Is the BEC guard any good?

I don't use them and I haven't had any problems over the several years I've been using multiple UG 430 units. Yes, they will back feed into the ESC/BEC, but only if the flight pack is disconnected. I just manually turn off the UG backup unit (hold button down for 2-3 secs) before unplugging the flight pack but, if I forget for a few seconds? No biggie and, again, never had a problem of any kind. It's impossible for me to forget and actually walk away because the disco ball LED "strobes" light off the second the voltage dumps because the flight pack is disconnected and you simply cannot miss those lights flashing in your face. If the model is in flight and actually coming down because the BEC failed, I really don't care about back feeding the BEC since it's dead anyway.

Besides, I'd need two of them for each model with two BEC leads and it's just that many more failure points. Plus, those suckers are expensive. LOL

[Porkster]

That's a big advantage of the Optipower Ultraguard 430. It detects system voltage automatically on on every power-up and sets its "trigger" point 0.5V below that, so it dynamically moves up/down if BEC system voltage ever gets changed. I run a couple on large helis and have never had a problem with them. I use the LED modules so I'll get bright flashing lights if the UG ever kicks in. Other than remembering to unplug the battery if you aren't going to fly that model for a while, it's about as fire and forget as can be. It stays charged/topped off from the flight pack and automatically turns on when it detects a flight pack plugged in so you'll never take off with dead weight as you might with the Scorpion BUG that has to be switched on/off manually.

I was told by the guys at optipower that the ultra guard can discharge to storage voltage automatically if you want, this is a set and forget process. Handy if you want to leave it for more than a few days. It will also top up charge whilst in flight if needed.
im very happy with mine and permanently leave it in my FW A-10

[Bandiferous93]

I was told by the guys at optipower that the ultra guard can discharge to storage voltage automatically if you want, this is a set and forget process. Handy if you want to leave it for more than a few days. It will also top up charge whilst in flight if needed.
im very happy with mine and permanently leave it in my FW A-10

Nope. Even though they haven't updated the manual, they took out the manual discharge to storage level feature unless it's a very old unit. Always unplug the battery if you're not going to fly that model for a while. My criterion is a week. It always uses a tiny bit of battery because it never fully shuts down. The storage level feature just put the battery down that much closer to being over discharged. It stays in a sleep mode waiting for BEC voltage to wake itself up. Leaving the UG battery plugged into the board for long periods is a great way to puff the battery. Optipower used to recommend unplugging the battery if you were putting it up for long-term storage like over the winter, but they now recommend doing it if you aren't going to fly it for a couple of weeks. Again, one week is my limit. It's okay to leave the UG battery "fully charged" because it never fully charges anyway. It's regulated to 4.0V/cell for this reason and to allow for diurnal (temperature) changes throughout the day. Lipo cell storage range is actually 3.7 - 4.0V/cell. People just focus on 3.85V/cell because it's in the middle of that range.