High voltage and other signs?

[REdiculous]

Anyone got a good warning sign on their bike? Is there a standard set? I guess I could look at the local hardware store when I'm in town again but maybe it's worth talking about...

If I get in a wreck and I'm knocked out for some reason I don't want someone to die because they messed with my mangled system...and it could be a deterrent for would-be thieves too.

When I'm done my system will peak near 1.5kw but I don't want to mention anything over 1000w...at least not prominently. Any good examples out there? tia..later!

 

[Demosthenes]

How many volts are you running at? Unless your over 50-60 the most danger I see is a short and some nice big sparks. Not likely to kill someone.

 

[Drunkskunk]

they don't put warning lables on cars, but the ignition system, grounded through the whole body of the car, is putting out 30,000 to 60,000 volts.
Those glow strip nightlights and the blue backlit watches have tiny stepup transformers to produce 10,000 volts
CRT TVs and computer moniters have hi voltage in the licture tube, which is a thin sheet of glas you let babies walk next to swinging there fisher price toy around hazordisly.

The hazards for electrocution are all around us, every second of every day. It aint worth worrying about. Unless you are the kind of person who thinks the warning label on a box of razor blades that it may contain sharp objects is a good idea and has very helpful information.

 

[SilverSurfer]

I on the other hand agree with some stickers. Everyone on this forum knows, voltage is only half the issue. Amperage is deadly. Im running 72v SLAs right now, They have 120a of thrust. Not too shabby! What can it do? One time I accidently let the two end poles meet.......WHAM! One battery post half gone, the other one down to the plastic! Only 72 volts, Im sure that blast pulled about 180 amps! Molten lead EVERYWHERE! No one got hurt.

My new battery pack is A123 M1 24s4p Very deadly amperage potential on a pretty high voltage. (at a quick guesse I think its over 300a continuous!) Im not even the heavy weight, many on our forum kickin that like its nuthin!

We have to be carefull ourselves. Not only are mistakes like I made expensive, they are dangerous in a bad way!

I have stickers! On the controll box, where the wires come out of the control box. Where the wires go into the saddle bags. On the entry handles of the saddle bags. And on the sb50 connector housings for main power.

Some visable is this photo...

I would say, if your over 2kw, it would be responsible ebiking to make emergency personel aware that your ride may be dangerously enhanced.

SS

 

[REdiculous]

I have a 12V DC battery, a 110V AC inverter and a 90/180V DC controller on a push trailer. 1.5kw on the AC side would hurt like hell at the very least - I dunno about the high voltage DC side. The inverter surges to 2kw (110v, 18amps AC..ouch!) according to the specs but I don't know how...if it just hits the battery harder then the battery is the limit...

My 20ah SLA seems to put out a good 600w, give or take, before the inverter complains of low voltage. I plan on adding 2 more, which in my mind increases the 12-14v potential to at least 125a. Maybe 200a or more tho since the inverter cuts out when the voltage drops too far. Could easily start a fire (hazard!) I bet but not too deadly otherwise probably.

I'm not super worried about it since I pretty much know what's safe to touch and accidents are accidents..hopefully rare/never. But 1.5kw is basically 2HP and that's chainsaw level, right? I do have a tensioner on one side that might save some hurt, but on the motor side the chain is tight enough and the teeth close enough that fingers could get crushed, ripped apart, broken or worse..

Some people might not make the connection that it's somewhat dangerous because it's made from bike parts and scrap (some wood even). Also the fact that it's electric means there's no motor noise even tho it's on. That's enough justification, imo...better to spend a word or two and a few dimes for the sake of safety I think.

SS, cool. Multiple places even..I like it. I may have to look at the chainsaw to see what it has for warnings. A buddy of mine is a paramedic so I know he'd approve of stickers too. No worries tho, to each their own.

 

[cell_man]

If you've got a BMS it will trip if something shorts out. They don't even fit fuses on most battery packs fitted with a BMS.

 

[amberwolf]

http://voltagecreative.com/blog/2008/05/not-only-will-this-kill-you-it-will-hurt-the-whole-time-you-are-dying/

 

[SilverSurfer]

http://voltagecreative.com/blog/2008/05/not-only-will-this-kill-you-it-will-hurt-the-whole-time-you-are-dying/

I gotta get one of them! That is epic! thanks

 

[justadad1957]

oh i like that lol

 

[REdiculous]

That is a good one..lol!

edit; no BMS so no protection there.

 

[Demosthenes]

Yeah, your running some pretty high voltages. I think some signs would certainly be nice. Here I was thinking like 36V or something, silly me

 

[REdiculous]

It's cool, no worries...I think I'm the silly one here..

I've got a treadmill motor running from an SCR (not a good combo so I heard) and the power needed to be converted twice in order to drive the motor more efficiently. Running at 36v would've limited the motor to 500w or so (iirc..edit; 666w) and it's a 1.5/3HP motor (cont/peak). It's not a normal hub or RC system at all but that's why it appealed to me...

I searched and searched and couldn't find a case of anyone trying this type of combination. It's pretty cheap to build over time too; $50 20ah battery, $80 1kw inverter, $85 controller, $35 motor..so about $250 in the drive system. 2 more batteries will put it just over $350 but then it should be capable of 2HP peaks (and 1kw for sure) so I think it was worth it...

I have no idea of the range or durability yet. It may really suck or I might be able to hypermile and get pretty far. The inverter draws 6w idling and is 87% eff max..but it actually requires more like 12-15w since I have to run a small incandescent light as well or the inverter chokes. The controller is around 98% eff and my gearing may be 80-95% eff...I forgot what brush motors are, like 90%? Total efficiency wasn't a real goal tho..I kinda just wanted to bump my rep with the stats...

Why do I need a motor that can peak to 3HP in a push trailer? Will I ever want to go the 45mph that it's currently geared for?..no. But being able to honestly say that it's capable of pushing 2HP will be really, really cool. That's the power of a 2-stroke pocket bike...in a push trailer.

I think I'll probably use the sign amberwolf posted and make it the biggest. I want to add others too though. I think under a big "High Voltage" sticker I'll put a little sticker w/ more detail..maybe "AC: 110v/18amp peak. DC: 180v, 9.2amp peak". If I can work it into one sticker I might do that too. I need to get a couple for the controller too but I need a real box for it first. I may mention the low voltage DC on/near the fire hazard sticker..not sure yet but I want it all to be neat, logical and fairly complete.

I'll probably add a big "1000w" sticker too..looking at the details you could figure the real power potentials but it's what the motor is fed that really matters as far as I can figure..so if I got a ticket based on the numbers on the stickers it might be easy to refute..they'd have to actually test it somehow to be sure, which they have no right to do as far as I know and the controller output is adjustable anyway. Enough of my rambling for now..have a good one.