Zepsus dual switch connections

[scottsware]

I just ordered the zepsus dual battery switch. After looking long and hard for a wiring diagram with Google and on the Zepsus website I have come up empty on how to plug it in.

The harness has two female and one male plug. I figure the main receiver battery goes into one female plug and the power from the ESC goes into the other female plug. I’m guessing the male plug goes into the receiver into the channel that controls the motor and I leave the battery connection on the receiver empty.

I'm probably over thinking this.

Any care to confirm my over thought?

Regards,
Scott

 

[Konrad]

Yes.

Most RX use a common bus bar for the RX power. So you can plug (power) into any open channel and the RX will work (power on).

As I think you are using an ESC with BEC is why you are plugging into the throttle (motor) channel. This is for the throttle signal to the ESC, not for any power needs.

 

[Konrad]

A follow up question, why the dual power supply with a BEC?

Most modern switching BEC are more reliable than the battery. Old linear BEC were easy to over tax as many folks didn't understand the heat (power) shedding requirements.

Can you tell us what your onboard power needs are? And what size/type BEC you are using?

 

[scottsware]

Thanks for the answer. Normally I don’t use something like the dual battery switch. I’ve never had an issue with a BEC. I'm going to use one in this case for an F5J Explorer. Two reasons. The lipo I’ll use for the launch isn’t overly large. The model is the most expensive I‘ve ever had so I was looking for a bit more “insurance” against failure. I got the idea from reading gliding forums and using the dual switch seems to be a common practic.

 

[Konrad]

Not knowing your set up. But would going to a larger flight battery be a better use of weight? A larger battery would allow for better motor performance (lower battery impedance).

Assuming that the voltage cut off is properly set and that the BEC has the head room to drive all those servos. You aren't likely to every use the weight of the back up battery (that is the goal). While it might be a common practice, is it appropriate for that class off of model. Are the big boys taking the weight hit.

Not sure what kind of insurance you are looking for. Or the performance hit you are willing to take for this insurance. Remember to cycle and charge that back up battery.

I've seen dead back up batteries as folks (me) tend to forget about them in their day to day flying and nightly maintenance (charging).

 

[scottsware]

It seems in the F5J world using the zepsus the battery used for the motor is the backup. The zepsus uses whichever battery has the higher voltage. Main battery is a 3400 mAh 2s lipo and will always have more voltage than the BEC, unless the battery dies then the BEC can take over.

I may reevaluate how I run the power setup at some point. You bring up all valid points in your post.

 

[Wayne]

I'd not use the dual switch with an ESC and BEC combo. Even if you should power it all through the switch, if you left the motor battery plugged into the ESC, it would still drain the battery as it is powering up the BEC and it is making voltage.

3400mah? Isn't that a lot of weight for that plane? I'm not well versed in F5J, maybe that is normal, but seems to me my locals are running 3S 850 or about that size. I would be tempted to set up a 2S setup and run the entire plane from a single 2S battery. Would have to hunt down the right motor option to get decent power from 2S. Simplicity and weight reduction usually work well.

 

[Konrad]

I love the mag switch.

With a 2 cell lipo do you need a BEC? Most modern F5J servos will run directly on 2 lipo.

I'm just pointing out other option that might help you get the most from your set up.

 

[Wayne]

Good point, not sure why he has a BEC in the mix since he is already 2S and I have to assume any servos used in a modern F5J should be able to handle 8.4 volts. Then again, we do not know what his receiver is capable of, recently found out some receivers can't handle 8.4 volts. That was a bit of a surprise to me.

 

[scottsware]

I thought the receiver battery was crazy big as well. This is my first large glider (3.8 meter) and when I ordered it from SoaringUSA I just excepted the package they put together. They seem to be the experts with competition class gliders. Perhaps 3400 mAh is used so you can run all day on a single charge at a competition?

The servos and receiver are rated for high voltage and will be powered by the 8.4 volt lipo. The BEC should never kick in unless the main battery goes sideways. If that happens the zepsus would switch power from the main battery to the BEC.

I did some googling to see what size battery is standard and so far, people only discuss what they use for the motor. 850 mHh is the one that comes up. It seems practically everyone uses a separate battery for the receiver. Not everyone uses the zepsus dual battery switch though.

I definitely will rethink the 3400 mAh battery though. It seems a 1200 mAh would be more than sufficient for the sport flying I plan to do.

 

[scottsware]

Sorry, I may have added some confusion. I am not using a separate BEC. The ESC will provide the backup power.

 

[Konrad]

Yep something seems backwards.
BEC is an electrical circuit. It can be on the ESC or a discrete device.

So your 3200mAh 2 cell lipo is the RX power source? I thought this large a battery was the main battery to drive the prop.

So the power (prop) battery is a minuscule 850 mAh (cell count?). What voltage are you setting the BEC/ESC to produce? I assume since your servos run on 8.4 you will not be setting the BEC to the (standard 5.1 v), but maybe 7.4v. Not sure why set the BEC to a different voltage than the RX battery?

If changing out the flight battery at each round, I see no need to have such a large RX battery. Each round of F5J has a time limit so there is no need to carry more battery than what is needed for this flight time, unless you need the nose weight.

P.S.
Is this your ship?

SoaringUSA > F5J/ALES Electrics > Explorer - F5J 3800 Ultra Light

Explorer - F5J 3800 Ultra Light

www.soaringusa.com

 

[scottsware]

For CG purposes the 3400 mAh and 850mAh (3s) are perfect. What doesn't seem to be perfect is the ratio. It seems the motor battery should be larger and the Rx battery smaller. I wasn't planning on changing the ESC/BEC voltage. Mostly the main Rx bar voltage needs to be higher then the ESC/BEC so the Zepsus switch uses that pack. If the main pack fails the Zepsus will the switch to the ESC.

I did notice something in my googling. Someone commented that in Europe they often just use a single battery while in the US it's common to use two batteries.

There is always a learning curve when exploring a new angle to RC flying.

 

[Wayne]

Can you share a picture of how people are placing the batteries in this plane. It makes NO sense to me to have such a huge battery to power the radio. The builder of the airframe went to a lot of work to keep it light and nimble, I doubt they wanted to see anything close to a 3400 battery in it.

As far as I know most people power with just the motor battery around here. These keeps the plane very light and they will only use the motor for a very short time. They swap batteries between flights as they are cheap and easy.

This is interesting..

 

[Konrad]

Is there a reason for not using the BEC as primary and using the battery as a back up. So where have you set the BEC voltage, a few 1/10th of a volt below the nominal voltage of the 2 cell lipo?

Not knowing anything about F5J to my way of thinking up the motor battery to say a 2100 mAh low impedance 3 cell (for balance). This will gain you some performance over the 850 mAh set up. Did you state which ESC/BEC you are using? Other than the YEP brand I've had rock solid BEC performance from all my switching BEC. Like I said far better reliability than batteries. (Yes, I've had both systems fail, SBEC & Batteries). May last battery failure was on the TX side of things.

 

[Wayne]

The Zepsus is a very simple device, it will draw from whatever power source has the highest voltage.

 

[scottsware]

The ESC is a Castle Creations. As far as why not BEC as primary I guess it's because I got that large battery on the recommendation of SoaringUSA. I looked for some good images of how others are placing the batteries but there weren't any good ones. I do notice opinions vary widely on battery combinations. So far the largest Rx battery I have seen other use is 2000 mAh while it 1300 mAh seems common.
Once I get this bird flying I will be experimenting with different battery combinations to see which is best. I do believe light is usually better.

 

[Konrad]

In post #12, am I linking to your ship? I don't see any SUSA recommendation for a RX battery. Was this a recommendation in your talks with SUSA?

ESC is an Edge lite or a Talon?

 

[scottsware]

That is exactly my ship. The ESC is the Edge Lite 50. The 3400 mAH was the recommend battery in the package. The website doesn't offer a recommendation as such. The recommendation came when I ordered the plane and other equipment. The one thing that I am changing is that it came with the Zepsus magnetic switch but not the dual battery switch. I figured if I was going to run two batteries I might as well buy the Zepsus dual battery switch.

 

[Konrad]

ODD? I find the prop batteries are showing up in the 115 gram range (3 cell) and the few RX battery set ups I see are 600 mAh 2 cell. These are placed aft of the CG as the long nose of the explorer makes it difficult to reach balance.

Is this ship built (set up)? Do you have experience with high performance sailplanes or high performance electric powered models?