tekin fxr lipo cut off setting

[dusty sweep]

Running 2 fxr's on 2s.


Looks like the only option for lipo cut off on the fxr is to set it to 6 volts using the led lights.

I am assuming this is to low and will kill the lipo.

Is the only way to set it to a higher voltage cut off is to get the hot wire pc connection.

What are you guys doing as far as lipo cut off goes.

This setup is in a xr 10. I am not comping just crawling.

Thanks

[BLKXJ 96]

Led's 1-3 on the cut off is 9 volts, you should be able to set this up with out hotwire.

[AreCee]

Set the cutoff to 6V. It's fine and does work, you won't kill your lipo.

If you're really that worried than get the Hotwire or fimd someone who has one and set the cut-off to something higher than 3V/cell.

[sporkfu]

I tried setting the LVC on my fxr with a Hotwire and it didn't work. I tried 3.3, 3.15, and 3.075V and each time the ESC started it lit up lights 1/3/5 indicating low voltage. The battery was 3s and read ~11.5V off the balance taps.

Unrelated (maybe) I cannot I cannot calibrate my ESC against my new radio, a 4PLS. The ESC detects neutral, but never registers the forward signal...

[mrG]

Using the hotwire sets the total pack voltage. 3.1 or 3.2 times the number of cells

[micro racer]

I have mine set to 6 volts, but it seems to cut off earlier at about 6.5 volts. It is probably seeing the voltage under load and cutting it then. Then the battery stabilizes to about 6.5 volts.

[sporkfu]

Originally Posted by mrG

Using the hotwire sets the total pack voltage. 3.1 or 3.2 times the number of cells

The issue was with the firmware. My ESC was running 028, so I upgraded it to 032. Now, LVC cutoff works properly, and the radio can be calibrated. Hurray!

[sporkfu]

Maybe the LVC cutoff is working, but I'm not aware when the cutoff happens... I have now dropped two (admittedly cheap) 1300mah 3s lipos under 9v. This is with the cutoff set at 9V, and later at 3.3V/cell. Here's my setup:

I have a pretty heavy Wraith with Mayhem Monster wheels and all Vanquish axles. I run a Tekin fxr with 35t motor, CC BEC, Hitec 7950TH servo, dig, winch, and Axial light kit. The ESC has 100% drag brake, and an exponential throttle curve. Typically I creep around very slowly on rock/dirt piles - I almost never open the throttle up to full speed.

In my go-faster days I would notice the LVC cutoff on my Rc18 or mini-Revo because the cars would slow down significantly. With crawling I never go fast, so I don't see this slowdown.

I'm pretty sure I need a low voltage alarm, because I'm not "aware" of when the ESC cutoff occurs at slow speeds. Do others have problem? Basically if you're a creeper, do you need another way to know when your pack is run down?

[sporkfu]

Well, I ordered the Hitec lipo alarm (Hitec TecTalk | Press Release: Battery Buzzer) so that should solve my problem. Still would like to know if others in the crawling community can't count on LVC because they don't "see" it...

[nharkey85]

I may not have a dual esc moa or the like, but regardless of how fast i run my scaler when my fxr hits lvc i have zero throttle input.

[sporkfu]

My FXR issues appear to have returned.

The current issue is that I can run for a minute or two, but then loose all power to the motor. All other components of the car (steering, lights, winch, and dig servo) continue to work fine. It now "feels" like the low voltage cutoff is being hit incorrectly, but the battery is freshly charged. If I can get my Wraith to move again, it will just lurch forward for a second, and then stop.

I flashed the ESC yesterday, and disabled the LVC all together, and the same behavior persists. Any thoughts?

I've emailed Tekin, but hopefully someone here can chime in if they think my ESC has finally died.

[sporkfu]

Tekin support is helping me out (very fast turnaround!) - I'll post back what they find.

[Ty@Tekin]

What motor? It's possible the brushes are worn out and not making complete contact. I don't think I've ever seen an ESC that runs a motor intermittently.

[sporkfu]

Originally Posted by Ty@Tekin

What motor? It's possible the brushes are worn out and not making complete contact. I don't think I've ever seen an ESC that runs a motor intermittently.

Tekin 35T. I can run for a few minutes everytime, and then the rig won't move, or will only lurch occasionally. Meanwhile all other electronics appear unaffected.


Sent from my iPhone using Tapatalk

[Ty@Tekin]

Originally Posted by sporkfu

Tekin 35T. I can run for a few minutes everytime, and then the rig won't move, or will only lurch occasionally. Meanwhile all other electronics appear unaffected.


Sent from my iPhone using Tapatalk

Have you checked the brush length? Once they get down around 5mm or less they will start to make intermittent contact and your rig will behave how you are describing sometimes.

[sporkfu]

Originally Posted by Ty@Tekin

What motor? It's possible the brushes are worn out and not making complete contact. I don't think I've ever seen an ESC that runs a motor intermittently.

The brushes were 9ish mm long. Unfortunately I frayed one of the brush wires during the removal so I'll replace that part before attempting any more runs.

[sporkfu]

Looks like my dig servo was the issue. It actuates just fine, but it also seems to be the cause of the power issues. When that servo is unplugged I don't have any running issues any more.