Also, the 25 minute flight was on the 7p24s battery…not the half hour 6p24s battery.
Bill
Also, the 25 minute flight was on the 7p24s battery…not the half hour 6p24s battery.
Bill
Flying my SP140 and 26M Independence Grasshopper single skin wing. It was a Very bumpy day with the wind out of the north in the Florida Panhandle. Wild ride!! The string “Delta” readings have been good since I reworked the batteries.
Happy Flying!
Bill
Ditto on the inverter thanks! Offered them $190 and they accepted. Just got it about 2 weeks later. Works great.
I have modified my batteries several times and Really got tired of trying to remove and reinsert the carry straps into those tiny slots and into the buckles…actually, I have broken a couple of the 3D printed buckles in the process. My solution was to take 1.5" wide Velcro and trim it down to 1.125" and cut 2 strips about 51 inches long. The longitudinal strength of the Velcro is very good, and the 2 strips work great! On my second battery (not pictured), I actually was in a bit of a rush and just used one of my rolls of 3/4" Velcro. That worked great too! I hope this helps.
Bill
Note in the last picture I show how much the Velcro overlaps. Once overlapped, you can’t pull it apart.
Coming back to this. I finally opened the pack to check on the 5th drifting parallel. Turns out the spotweld detached from the cell! After the fix the drift is much smaller. So What I have been doing is flying one string on 10 cells instead of 11. Well, partly as it did have some contact due to compression from the case.
You were very fortunate that you found it on the end of the string …although, you could have hit the end of every cell in that string with a couple of new spot-welds.
Good work!
Bill
Finally, an hour window for flying after days of waiting!!! Yippee!!!
Also, my OpenPPG SP140 Atom80 “ice” unit for LONG XC flights came in today!!! Thanks, Paul!!
It was a Very good day!!!
Merry Christmas, Y’all!!!
Bill
Here’s a repost of the link to my SP140 album. I will be sure to post the SP140 Atom80 “ice” photos as I put it together. Hopefully it may help someone.
Bill
I would like to learn about making this wire solder joint of Josh Bixler of Flite Test.
I’ve started using it recently at my battery ends from the cells to the main negative wire, after my first joint with twisting method was very bulky, but this one is great, no more bulky joints. Very easy to do after watching the video. I’ve stripped about three inches of one normal, socket type wire and had a lot of thin wires to go arround the future joints, used a couple twisted together because just one was too thin. The fact that the final joints are just slightly larger than the wire and incredibly strong is fantastic. Don’t forget to slide the heat shrink tube first, and a thiker soldering wire helps because a thin one takes a while to fill the joint.
Wish I knew this 20 years back.
Yep, I use a 100 watt iron and a 120 volt controller. I think the controller came from a stained glass supply store online. Works great! I thanked Josh for the video several years ago during some of our correspondence regarding OpenPPG. The controller picture should be in my SP140 album.
Bill
My SP140 BMS has “dumped” me (cut off in flight) 4 times so far since early in 2021. My X4 has no BMS, so, it has never cut me off in flight. I decide to think about landing my X4 when my batteries reach 40VDC. My batteries are 5 years old, still solid and still provide me good service. Anyway, I want to be responsible for the health of my batteries…not a BMS designed to service li-ion and lithium iron phosphate stationary storage batteries. I needed to replace a faulty Bluetooth BMS and decided to “bypass” it and make my SP140 battery like my X4 battery.
The AS150 connectors are the charge connectors. I am going to replace them with a single XT90AS. The XT90AS on the Anderson is connected before the Anderson to eliminate any spark. Nothing perfect about any of this, but it removes a degree of anxiety from my flights. The battery health is now my responsibility…and I am much happier with that. Hopefully, a better BMS will be available in the future and the setting on the ESC to reduce power at a certain voltage will become active. This is an opensource project and a work in progress…and I am good with that. Electric is the best!!
Bill
Did you eliminate the bms completely or just the output power cable to the motor avoids it, but the charging and temperature monitoring is still through bms?
Because on the X4 I think you had lipos, that you balance charge them with a hobby charger.
Did you used those small lipo cell voltage alarms during flight?
I only use the BMS to charge the battery (AS150 connectors). The output power cables bypass the BMS. The BMS will still monitor the temperature and string voltages and “passively” balance the strings while charging. My installed “active” balance unit works 24/7 as needed. It also monitors string voltages. When I fly, I monitor the voltage and decide when to safely land my aircraft…not the BMS anymore.
I did not use the voltage alarms because in a hard climb, the voltage would drop, the alarm would go off…and would continue to go off…even though the total cruising voltage was over 40VDC.
Bill
Here is a link to my build. Skip down about 2/3s of the way in the album, and you will see the Daly active balancer that I am using. It saved both of my batteries. I have it mounted inside of the case now.
I finished bypassing my 6P battery BMS, made my charge adapters and checked out my “spare” Ali Express charger.
Hopefully, I’ll get to fly with this battery in a few days…if the weather improves in the Panhandle.
Cheers!
Bill
I received my OpenPPG V2 Atom80 just before Christmas and finally got to break it in and fly it yesterday. As with all new PPG equipment, I tend to overthink the change and get a bit nervous, but this machine got me right off of the ground without any problem. I weigh just over 180lbs and had an instructor tell me that it was not a good idea to buy an Atom80. I had a blast yesterday!! It is going to be a terrific XC machine for me, and on low wind days, it will be perfect with my single skin Grasshopper. I am so happy that I bought it! Thanks, Paul and Zach!!
Cheers, Y’all!!
Bill
I love the Atom 80! Easy to start! Light weight! Fuel efficient! Plenty of power to fly me at almost 200 lbs even at 4500 ft elevation. Dead wind takeoffs require a little longer runway but that’s not usually a problem where I fly.
Hey, Paul!
I’m going to finish my “flying break-in” tomorrow. The weather in the Panhandle is suppose to be good for the next 3 days.
On Thursday the wind is predicted to be Very low in the afternoon, so, I will be doing reverse launches with my Independence single-skin Grasshopper. My Grasshopper has made my nil wind days so much better!!
Bill
BTW: My Grasshopper was the only way I could get off of the ground at 7,500’ with my SP140 in Sport mode in Salida, CO during the summer.