Sorry, no video here. I found out quite by accident how to get stunning performance from a heavy lift hex, feed it 32 volts! I got the two 4S 5000 packs I've been waiting for on Thursday, Friday I put connectors on and did the first test flight, still had 40% battery capacity after 10 minutes with the packs wired in parallel.
Late yesterday I decided to give it a go at 12 minutes to see what was left in the packs then. Quickly grabbed the TX and a connection harness off the bench and went out in the yard, connected the batteries, initialized and then started the motors. I noticed the motors seemed to be idleing a bit fast but didn't think much of it, then I gave it some throttle. HOLY CRAP!!!
You would not believe how fast a 7 1/2 pound hexa can climb if you give it enough voltage, I mean it was crazy, like the thing had JATO motors attached and that was at less than 1/2 throttle. Immediately I knew something wasn't right so I gingerly brought it back down from orbit and just as I landed the cap on the F/C blew, I yanked the plug just as that was happening.
Wasn't until I got back in the house and put my glasses on that I could see my mistake, I grabbed a series connection harness instead of a parallel connection and was feeding double the voltage to the MK electronics, approximately 32 volts at full charge on both packs. No wonder it had stunning performance the motors were supercharged!
I definitely have to give Holger and company credit for building the electronics robust enough to survive a bonehead move like this. I could easily have fried just about everything in the stack if it hadn't been able handle the volts, but all that happened was a blown capacitor, everything is still working normally, thankfully.
Also a lesson learned, don't assume that I have the correct power connection in hand when I use both parallel and series connectors that at quick glance look almost exactly alike, put the D**m reading glasses on and look at it before plugging it in!
So now I have to pull the boards off the stack and replace the power cap on the flight controller, but that's a cheap price to pay for what could have been a many hundreds of $ mistake. That little project will have to wait though, in a couple hours I'll be settled into a 737 winging my way to Texas for the week on business.
I'll be checking in as time permits but this is going to be a very busy week with a lot of meetings, so you probably won't be seeing me here much until next weekend.
Have fun and keep flying, I'll be back soon...
Ken
Late yesterday I decided to give it a go at 12 minutes to see what was left in the packs then. Quickly grabbed the TX and a connection harness off the bench and went out in the yard, connected the batteries, initialized and then started the motors. I noticed the motors seemed to be idleing a bit fast but didn't think much of it, then I gave it some throttle. HOLY CRAP!!!
You would not believe how fast a 7 1/2 pound hexa can climb if you give it enough voltage, I mean it was crazy, like the thing had JATO motors attached and that was at less than 1/2 throttle. Immediately I knew something wasn't right so I gingerly brought it back down from orbit and just as I landed the cap on the F/C blew, I yanked the plug just as that was happening.
Wasn't until I got back in the house and put my glasses on that I could see my mistake, I grabbed a series connection harness instead of a parallel connection and was feeding double the voltage to the MK electronics, approximately 32 volts at full charge on both packs. No wonder it had stunning performance the motors were supercharged!
I definitely have to give Holger and company credit for building the electronics robust enough to survive a bonehead move like this. I could easily have fried just about everything in the stack if it hadn't been able handle the volts, but all that happened was a blown capacitor, everything is still working normally, thankfully.
Also a lesson learned, don't assume that I have the correct power connection in hand when I use both parallel and series connectors that at quick glance look almost exactly alike, put the D**m reading glasses on and look at it before plugging it in!
So now I have to pull the boards off the stack and replace the power cap on the flight controller, but that's a cheap price to pay for what could have been a many hundreds of $ mistake. That little project will have to wait though, in a couple hours I'll be settled into a 737 winging my way to Texas for the week on business.
I'll be checking in as time permits but this is going to be a very busy week with a lot of meetings, so you probably won't be seeing me here much until next weekend.
Have fun and keep flying, I'll be back soon...
Ken
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