wesnewell said:
Matt Gruber said:
with 24s, i'd use higher ohms even 1000
3-5 watt. sure 150 will work too. anything 150-1000.
i'm thinking of trying a high class LED with R
so the LED dims as it charges up.
way more entertaining!
I started with a 520 ohm 10W resistor. It still gave a big spark. 2 of them in parallel (260 ohm) still gave a good size spark. 3 of them got just a tiny spark. It was just a big bundle so bought a pack of 10 150 ohm 10w resistors off ebay for about $5 shipped. I've used these with 1500uf - 3000uf caps and voltages up top 100V and they work perfect.
Did you try the 3 value's in quick precession? It seems to go against the laws of physics. Smaller resistor equals bigger power flow, so bigger spark. Unless the caps were actually empty for the 1st try, not so empty for the second, and less so for the 3rd.
My guess is the cap/s are on the controllers input, so would become flat very soon after disconnection. Drained by the cpu. Then you come along with your battery and try to power the load, it looks a lot like a short circuit. The caps present this short when flat, and as they charge the voltage difference between them and the battery gets smaller and smaller, so the power flow decreases, until the caps are fully charged and flow about stops. Thus, as the moment of connection the only limit on flow comes from your resistor. A simple ohms law I=V/R if you ignore the barely mentionable battery resistance and what-not.
Q: When you get a spark, if you disconnect and reconnect quickly is it gone? I'm trying to understand how quick the caps actually discharge after disconnection.
I wonder if something trick could be made. A way of starting with a large resistor and switching to a smaller one after charge comenses. A the moment of connection full battery voltage appears across the resistor, which falls to nothing as the caps charge to full. We could watch this using electronics battery side. Have a large resistor that takes forever to charge the caps so makes no spark. Watch the voltage over it, and as it drops, switch in resistors in parallel to speed up the charge rate. You could have no spark and rapid charge. Perhaps it is just a bit silly though unless you have massive voltage and capacitance to deal with.
I just connect quickly and surely, like a sprung switch. If I start to see any erosion I will fit a smaller parallel lead to do the initial connection before I connect my main. I'm not suffering, but I do design around not disconnecting very often. My currant project is still a wee small s12s though, claiming it barely touches the battery when not on. Something about the lcd containing a battery, but mine has no screws. Anyhow.. No personal need to disconnect leaves me interested but clueless...
. So could somebody suggest a suitable value & type of resistor I could use to calm things down 
Just commenting because I'm having the same issue. I actually melted the prongs in my connector yesterday. I made like a connector adapter for my pack so I could use it on either of my motors. The first time I plugged into the controller it was fine but then the splices I used came loose so I had to re-splice it. When I connected it again it sparked and I thought that was normal but then it wouldn't stop sparking. Apparently I spliced it backwards. So now I'm just using the battery for my newer kit and gave up on the adapter idea. Luckily all I did was damage the connector and not myself or the pack. It still sparks when I connect it but that's because I don't have a switch installed. You could get something like the on off switch that Currie uses. I use one for my front kit and it works fine. You can find them on a couple different scooter parts sellers sites. Try monsterscooterparts.com, electricscooterparts.com or tncscooters.com. Here's a pic of what one looks like.
