24-Jan-2021, 04:13 AM
Hi everyone,
Having a few issues with my GEPRC Phantom HD, and unsure if they are related.
Recently I have been seeing more battery sag with my GNB LiHv 4S 450mAH 80C batteries when doing any high thrust maneuvers or punch outs... These batteries are around 6 months old, probably around 20-30 cycles on them, always charged the day before flying and storage charged after use. Average internal resistance is around 20mOhms, which is apparently fine.
I tried ordering a new set of the exact same battery and even with the brand new set I am seeing the same voltage sag and power loss on punch outs.
I tried ordering a set of Tattu 4S 450mAH 70C lipos to see if they were better quality, unfortunately the internal resistance on these was 30-40mOhms when they arrived. They also have poor performance on any high throttle maneuvers and even performed worse (in my opinion) than the GNB LiHvs that I usually use.
Thinking that the internal resistance was really the issue, I ordered a set of the Tattu R Line 650mAH 4S batteries which have a 95C rating.
When I tried flying with the 650mAH Tattu R Line the drone took off with minimal throttle input but continued to climb even after I lowered the throttle to 0. As the quad continued to fly off out of control I was forced to disarm the quad mid-air. Luckily it landed in the grass (learned from too many other crashes).
Thinking that this issue was due to the new R Line battery I tried putting one of the previous GNB 450mAH batteries back on to fly and found that one of my motors couldn't spin up properly.
Done for the day I went home and replaced the motor (a skill I am learning too quickly).
I took the GEPRC Phantom HD out again today and was testing out the lower capacity Tattu 450mAH 4S battery and was again having issues controlling the power to the motors with the throttle, it seemed the power was either non existent or max with just a little bit of throttle input. After landing safely and removing the battery I checked the remaining voltage and was surprised to see it register only 3 cells, then 7 cells, then 4 cells... suffice to say I am losing confidence in this battery.
After narrowly escaping a crash with the Tattu battery I went back to the tried and true GNB LiHv 450mAH and flew one pack. I was not pushing the quad hard, just cruising around when suddenly the drone was spinning out of control towards the ground. Another motor failed mid-aid, but this time on a battery that Ive flown many many times before with no issue.
So with all this backstory my questions are:
1. Is there something that could be wrong with my drone that is causing the poorer performance in punch outs with otherwise fine batteries?
2. Is there something that could cause motors to blow at a higher rate than would be expected due to wear and tear?
3. Is there something that I need to change with regard to PID loops (never touched them before) or anything else in Betaflight to use the R line batteries on this drone?
Having a few issues with my GEPRC Phantom HD, and unsure if they are related.
Recently I have been seeing more battery sag with my GNB LiHv 4S 450mAH 80C batteries when doing any high thrust maneuvers or punch outs... These batteries are around 6 months old, probably around 20-30 cycles on them, always charged the day before flying and storage charged after use. Average internal resistance is around 20mOhms, which is apparently fine.
I tried ordering a new set of the exact same battery and even with the brand new set I am seeing the same voltage sag and power loss on punch outs.
I tried ordering a set of Tattu 4S 450mAH 70C lipos to see if they were better quality, unfortunately the internal resistance on these was 30-40mOhms when they arrived. They also have poor performance on any high throttle maneuvers and even performed worse (in my opinion) than the GNB LiHvs that I usually use.
Thinking that the internal resistance was really the issue, I ordered a set of the Tattu R Line 650mAH 4S batteries which have a 95C rating.
When I tried flying with the 650mAH Tattu R Line the drone took off with minimal throttle input but continued to climb even after I lowered the throttle to 0. As the quad continued to fly off out of control I was forced to disarm the quad mid-air. Luckily it landed in the grass (learned from too many other crashes).
Thinking that this issue was due to the new R Line battery I tried putting one of the previous GNB 450mAH batteries back on to fly and found that one of my motors couldn't spin up properly.
Done for the day I went home and replaced the motor (a skill I am learning too quickly).
I took the GEPRC Phantom HD out again today and was testing out the lower capacity Tattu 450mAH 4S battery and was again having issues controlling the power to the motors with the throttle, it seemed the power was either non existent or max with just a little bit of throttle input. After landing safely and removing the battery I checked the remaining voltage and was surprised to see it register only 3 cells, then 7 cells, then 4 cells... suffice to say I am losing confidence in this battery.
After narrowly escaping a crash with the Tattu battery I went back to the tried and true GNB LiHv 450mAH and flew one pack. I was not pushing the quad hard, just cruising around when suddenly the drone was spinning out of control towards the ground. Another motor failed mid-aid, but this time on a battery that Ive flown many many times before with no issue.
So with all this backstory my questions are:
1. Is there something that could be wrong with my drone that is causing the poorer performance in punch outs with otherwise fine batteries?
2. Is there something that could cause motors to blow at a higher rate than would be expected due to wear and tear?
3. Is there something that I need to change with regard to PID loops (never touched them before) or anything else in Betaflight to use the R line batteries on this drone?