Water is great for heat absorption too (as if you didn’t know)! You could get all crazy and route a water cooling loop to the battery pack and motor to try and simulate the cooling effect from riding, or just keep temps down in general during testing.
don’t tempt me. I ran a water cooled pentium 4 dual core for a couple of years as a gaming rig. I still have the heat exchangers and pumps. next thing you know we’ve got water cooled battery packs, soft switches, and VESCs.
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Oh, I would NEVER try to tempt you. Besides, I don’t think you’ve got the skills or cajones to make it work anyway. 
jk
And how cool would that be to run a water cooled system through some visible vein/tube system in the deck or enclosure and fill it with water dyed a crimson red color? Scarlet would have her own working circulatory system. And illuminate the whole system so it looks super sweet, while your at it.
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If you want to replicate cooling from riding, why not have a fan be the load? Just get a RC prop (which will obviously fit on a brushless motor) and have that be the load.
Build a bench test rig using a prop and a coulometer on a large motor. Cheapest way to get it done. Be careful though, you can easily pull enough wattage to ruin some gear.
This guy rigged up a thrust gauge but it isn’t needed for our use.
Oh yeah, almost forgot. This is very dangerous, it can kill you!
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Used a simple online circuit design tool to come up with this.
It’s 2s2p 25ohm 100w resistors. Based on the calculations total drain should be 1.8a, and each resistor should be burning off a little under 20w or so; well under the 100w they are rated for. Interestingly at this low wattage they are still too hot to touch.
Running them in a 1s4p configuration would result in about an 8a current, and each resistor would be pushed to 80w. Given how hot they are now I’m not too keen on testing this. Might look around to see what else offers a suitable resistance for higher currents (and is able to sustain them) without costing too much.
I use the watt meter for charging, but it’s handy here. Looking to see if the capacity just before it (hopefully) gets shut down by the BMS matches what it should be. Speaking of which, the DieBieMS spits out everything the watt meter does but also includes individual cell voltages so it’s kind of a little redundant in this case.
You could put your cup off coffee on there so it doesn’t go cold or you might as well just boil the water for your coffee with it
Hmmm, might just get the multimeter out to probe the resistance of the kettle🤔.
We use electric kettles for boiling water round these parts; recently I was lead to believe this is quite the novelty in the US.
Not sure whats the situation where u live but u could try to find decent power tool li ion packs.
These should have high drain batteries inside of them, usually already spotwelded.
Those high power resistors are meant to be mounted to a larger metal heatsink for cooling. Your carbon cellulose slab is not an ideal heatsinking material 
(You probably just wanted to attach them to something, fair enough)
But for reference, something like this. Might not even need anything huge size wise, if you add some fans for forced convection cooling.
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That’s basically a HiPOT, which is something i need. They’re used for load testing and discharging. Most people use lightbulbs now because they’re cheaper than these huge resistors that also require some kind of framing and have to be kept away from everything.
maybe there’s a fancy way to make a hipot out of lightbulbs. Maybe some kind of hilarious sign full of bulbs.
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Just hang a bunch of em up all around your work shop. When it goes dark plug em into your skateboard and poof your shed is lit. Oh and make sure to get multi coloured ones 
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LHB -Best bet is to get an 8 ohm 100W wirewound resistor (Got mine from Aliexpress) and do a full discharge test from 42V to 30V (for 10S) with regular voltage readings of each cell pack. This will show up any dud cells.See my blog at https://evolveforums.com/threads/bamboo-gt-at-50km-range-project.1169/page-7 for how I did it .Check voltage and AH against cell specs -use exel for graphing and ah calculation -I can send file to you if you want. Note fan for cooling of resistor . 8 ohm at 40V will give 5 amp and 200W -but with a fan 100W resistor will be fine
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Liked your idea so much @SkaterBoy58 I, errrr, stole it 
Wrote some python code to periodically poll the DieBieMS and write the data out to a CSV file I could create a chart from fairly easy. I’ll give a few more details on this over in the other thread.
a123 LiFePO3 based pack, so if the voltages seem a little odd…
Discharge was no more than 1.6a, so I really wasn’t expecting to see much drift across the cells. Having a less well balanced pack probably would have made for a more interesting chart though.
One of the nice things about the DieBieMS is how it tracks state of charge, and doesn’t just base percentage remaining off the current pack voltage. It’d be tough to get a reliable charge % based on the voltage change shown above. Red line seems right as the pack was drained using a constant resistance.
Will be interesting to run the same tests after the pack has been used for a while.
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Maybe use an engine starter? But it probably draws way more amps than batteries for eksate
I just noticed the wood under the resistors is singed 
.
Do you have any spare fans hanging around? Just some forced airflow over them would greatly increase their heat dissipation
no worries -ideas are for sharing here My DIY pack is 10S8P with MJ1 cells so about 1000wh in total-explains the long time for my discharge test!
.I used a 200W load to simulate average riding conditions . That is at 20km/hr and 10wh/km =average of 200W .
Cheers
Just letting you know but the 10wh/km is for distance referencing not speed. Although it may work for speed too but I don’t think it does
Nah 10wh/km is typical board energy consumption going at 20km/hr Cheers