How to setup a resistor bank for 40A discharging

[@vendettasnares]

What does it mean to "use balancing for 1S" you're talking about at 1:57 ? Because for 1S there is nothing to balance.

[@Pswans509]

Thanks for the help video!

[@bstearn1653]

In the video at 4:20 you say the resistor bank is plugged into the second channel but earlier it was shown plugged into Channel 1. Did you change it before running the Discharge?

[@hagberg]

You can plug it into either channel (opposite of the battery), the other channel will always be used for regenerative mode.

[@bluegroovemodelsports9650]

Great video, always great tips .

[@thomasweber3559]

Hallo Alexander möchte mir so eine Discharge Resistor Bank selber bauen was genau würde ich benötigen oder wo könnte ich so etwas Kaufen

[@MrBratius]

Will this work with the 406X as well?

[@jas-FPV]

What resistance is needed ? I guess the charger will apply a CC profile ?

[@hagberg]

@jas-FPV good IR for these types of packs, as measured on iCharger, is around 1.0 or thereabouts.

[@vendettasnares]

Looking at current and voltage near the end of discharging it's around 0.93 Ohms. If these are the same type of resistors - which the should be 😁 - then it's most likely 5 x 5 Ohm power resistors in parallel.

[@dameetz]

Hi Alex, on the LOAD side, do you know why the Voltage is higher than the battery side, is this normal? It also shows the Amp on the LOAD side is not reaching to 40Amps as you set on the battery side. Is this because of the resistor bank spec? I ve just made mine and tested it, the reading is almost the same on both page for Volt and Amp, i m wondering if there is something i did wrong with my charger set up or my home made resistor bank.

[@hagberg]

Did you crank the voltage and current limit all the way up as advised in the video?

[@dameetz]

Yes I did

[@vendettasnares]

All your questions are connected. 1. Why there is not 40A on load side? As you can see power on both channels is roughly the same - 280W, so when the current is maxed out on battery side, the maximum discharge power is reached. Resistor's bank resistance is around 1 Ohm, so for X of applied voltage it will roughtly be X amount of current. Disregarding units X * X = X^2 = 280 -> so X is a square root of 280 which is ~16.8. It's not exactly, that, because resistance is slightly lower, but I hope you get the point.

[@vendettasnares]

2. Why is voltage higher on load side than on battery? I understand that regenerative discharge's general idea is to charge another battery while discharing other. And in this situation charger can boost voltage if required. We can use that to our advantane in order to "push" as much power. Imagine situation where battery is connected directly to resistor bank - for 1 Ohm resistance and 7V on battery we would only get 7A of current, giving around 50W.

[@griffinmpc8144]

I have a 458 Duo and recently bought a Cell Master SPECTER Discharge Resistor Bank - but can't get it to work. The bank has a balance cable which does not fit the 458 Duo - and I haven't been able to get it to work. Any ideas here? Will it work if I change the balance cable connector? Thanks for all your great videos!

[@hagberg]

Hi, the Specter discharge bank is compatible with the Specter charger only (from what I understand).

[@griffinmpc8144]

@ thank you for taking the time to reply! Much appreciated!

[@JONESSFCY]

Can you show how to set ip the cycle (discharge first and charge) with defined resting time in between? Thank you again for always bringing valuable info. Loving the “stock” racing related videos.

[@hagberg]

It's fairly easy to do. You need to go into the LiPo Cycle Set-up. Set it do DCGH->CHG, cycle count 1, Delay time - I would suggest 3-5 minutes

[@JONESSFCY]

Got it. Thank you so much

[@jasonchavis6414]

When I’m at the race track for the day do I discharge in charge every time I need the battery for a race?

[@hagberg]

Correct!

[@paullampa4484]

I just got a 458duo and it will not discharge with a discharge bank plugged in to channel 2 and battery in to channel 1. My 308duo can have discharge bank in either channel. Do you have any idea why?

[@hagberg]

It works on one channel and not the other? Or not at all?

[@thomsonchong3248]

Hi Alex, What is the reasons to cause lipo batteries get swollen😢 We even set the HW speedo to cutoff voltage...nothing less than 3.3v/cell We race 1/8 GTe

[@hagberg]

The main cause is too much load, or when run until too low voltage. Too many heat cycles can also wear our out the battery quickly, some brands seem more suspectible to "puffing" than others.

[@thomsonchong3248]

what is your advice to reduce the load😊

[@hagberg]

@thomsonchong3248 make shorter runs, reduce turbo and boost in the ESC. Shorter gearing.

[@jasong712]

So, these discharges do nothing more but discharge the battery quickly and safely of course?

[@hagberg]

@jasong712 correct, the discharge bank allows for a higher discharge rate than if you would use the charger alone.

[@slappomatthew]

1s balancing is something I will never understand.

[@jorgemalafama7196]

are the resistors 1 oam? or more?

[@vendettasnares]

These must be 5 x 5 ohm resistors in parallel making total resistance of this discharging circuit 1 ohm. If it was 5 x 1 ohm resistors then total resistance would be 1/5 or 0.2 Ohm.