OK, just rolled in with

Nice job! You should make battery recycling into a business!

Well, I thought about it, but apparently copper recycling is more profitable.

I've read several stories lately about thieves stealing copper. In Halifax harbour, someone cut up an 11 km long copper cable from a dock crane that will cost $100,000 to replace. They were only able to actually make off with about half of it though. Crazy.

Yes, I've seen stuff like that online, that's it's big and all.

Last year when I worked at the shop the new guy would always talk about how people would steal the rain gutters and things for aluminum scrap. Crazy times.

And that bungee cord connected to the top battery rack? It's holding up the forward end of the electrical conduit I put under the car on the weekend. Now that we know where the controller is going to be, it can be cut off at the proper length to run the cables where they need to go.

When's the date with the registration peeps?

It would be nice to have it on the road (legally)

You're only about a year behind schedule then! Good job, governor.

https://re3.mm-a7.yimg.com/image/3799019197

?

I think you've found it (it cuts to the quick). ;)

will 200 amps do? $16 currently
https://i18.ebayimg.com/07/i/000/9e/a8/37f1_1.JPG
https://cgi.ebay.com/Cutler-Hammer-2-...QQcmdZViewItem

Will an AC circuit breaker work for DC? There is 300A worth of service disconnect breakers at my local goodwill for $2 ea. Didn't buy them because I wasn't sure they'd work for DC.

I honestly don't know.

I just read this yesterday, but can't comment on it:

But then again, wouldn't a knife switch work on either AC or DC? It's just a simple switch. It would seem to me it's all about the current rating, and that's where you need to be careful. You probably can't apply AC ratings to a DC circuit.

I don't see a problem using an AC switch in a DC circuit (though not the other way around).

The AC switch has to be over-engineered somewhat because it will see higher voltages. The 110v rating is actually the RMS rating (area under the curve basically), the AC voltage is actually a sinewave that goes all the way up to 170 volts (and higher peak current also).


If you had 110v dc and 110v ac (rms) and hooked them up to a heater coil, they would both produce the same amount of heat.

So, unless we find something that says there is more mojo to it, it *should* work fine.

Apparently mr sharkey indicates greater arcing potential in DC (though AC is even better at arcing?!?)
https://www.mrsharkey.com/busbarn/electrics/chapt9.htm

But you are at 48 volts, and this breaker regularly sees 170 volts. And you wanted cheap ;)

Hmm, I remember from A&P school that DC switches have to have a higher rating than an AC switch because of the arc caused by turning it on or off. AC is able to sustain an arc, but a DC arc does more damage. This is why TIG welders have an high frequency AC 'starter' circuit, then once an arc is established, it switches over to the high-current DC.

I'm looking forward to seeing how you made your terminal ends. I'm getting to the point where I will need some, and I'm planning on using your method.

Turns out there's a discussion about this on the EVDL this week. The issue is DC arcing, and one of the old hands says:

He recommends going 3x over the AC rating for DC use:

https://www.nabble.com/Clearing-the-a...html#a12646307

Mouse: I'll post a description of the lug making process soon, and come back and add pics later. I haven't made any new ends since last weekend. This weekend will probably be spent figuring out how to mount contactors etc.

I did sneak out and replace my fried potentiometer today though. :)

While tinkering on the potbox today, I got to thinking about the various sources for recycled parts used in the car so far.

Quick cable end-making tutorial for lemmiwinks, Bigmouse... I'll add pics when I make my next batch of ends.

Added a few pics to the cable end DIY, above.

Made a few more cables this weekend, and noted that the forklift cables we have used so far are all 3/0, not 4/0 as previously thought. The lugs all say 4/0 on them (the source of my confusion), but the cable itself is 3/0.

Also, I made a cable end lug with coarser strand 3/0. It didn't turn out quite as well as the fine strand stuff - more prone to cracking when flattening/drilling as I suspected it would be. But it worked OK.

I ordered myself 30 feet of 3/0 welding cable (fine stranded stuff). Hopefully I'll get enough area out of the end to drill the 1/2" holes for the lugs on the motor. I may just have to splurge on the the 6 or so cable ends I'll need. NiCad battery cells use solid interconnects, not cables, so I won't have all that many to do. Good info though!

You should be able to get the area for 1/2 in. holes. It's up to you really - how much you flatten the end before/after dipping it in the "solder pot".

How much voltage have you collected so far?

Added a refinement to the end-making DIY:

You don't have to pre-fill the solder pot/crucible. You can just feed solder into the side of the cable at the neck. It's heavy - it'll run down the strands as well as up.

Like a KillaSwift? :eek:

Yep! 'Cept that wasn't controller failure, that was full-on wetware failure! :)

Fortunately, neither he nor the bike (nor the minivan) were really hurt.

Is this a problem? I've done a bit of EV reading (likely not as much as you) and I haven't come across a "WOT" controller failure (yet).

So theoretically, turning the ignition off (in this worst case scenario controller failure) would do the same thing on an ignition based contactor. I know, split second reaction time lost....

So is it really a problem?

I'm up to about 68 volts worth. About half way there :-)

You know, in the year and a half I've been following the EVDL, 2 Cursit failure stories jump to mind (there are undoubtedly more) - and they were "fully closed throttle" failures.

I haven't actually read about a WOT controller failure, though I'm sure if you ask on the EVDL, you'll get some.

Still, everyone insists controllers will fail fully on, and they're basically ticking time bombs...

Note re. controller failures: DC controllers may fail ON. Apparently this is one of the other benefits of AC, which fail OFF.

---

Clack, clack, clack! I hooked up a second, identical contactor, this one not bolted to the unibody, and it's much more reasonable in terms of noisyness. Still louder than nothing, but nowhere near the volume of the shock tower mounted one ... probably acceptable.

So it looks OK if we can soft mount the pack +ve contactor and run it off the low pedal potbox microswitch. I'll probably still try to insulate it to keep it as quiet as possible...

People keep asking me how much it costs to drive (recharge) the ForkenSwift. So without further ado...

After 20+ km of driving, the pack takes about 24 hours to recharge, using the slow, "semi-smart" (voltage sensing, auto shut-off) 24vdc/10A charger. That's splitting the pack, 12 hours on the back 4 batts, then 12 hrs on the front 4.

Yes, 10A is that slow.

3.6 amps (24v charger) at 120 volts AC =
432 watts total

24 hours per charge for 25 km
10368 watt hours per charge

@ 6 cents per kwh (standard Ontario energy mix rate - Ivan's house)

0.62208 $ per charge
25 km/charge
0.024883 $ per km
2.5 cents/km

@ 9 cents per kwh (100% renewable energy rate - my house)

0.93312 $ per charge
25 km/charge
0.037325 $ per km
3.7 cents/km

Compare to gasoline cost for the Blackfly @ 75 mpg (US) & $1 / L ...

3.14 L/100 km (3.14 = 75 mpg (US))
0.0314 L/km
1 $/L
0.0314 $/km
3.1 cents/km

Nice price write up! Make ivan get the same power you have now...

Just realized I can calculate the car's energy efficiency from these figures...

(10368 wh / 25 km) / 1.61 km/mi = 257.59 wh/mile

And that's based on charging. Discount the charging inefficiencies (as I believe is standard practice in talking about wh/mi), and it's better than that. I'm not sure what the charging efficiency is though.

Soon there will be no more 48v cables

You're crazy, you know that?

Spent some more time on things this weekend

Oh, and trebuchet - I was talking to someone last week who made an electric outboard (DC with lithium) and experienced controller failure (overheated it) ... it failed fully on.

:eek:

I think the single task I've spent the longest on so far is this

Whee! I guess I just won this