Building a water resistant electrical box

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Deanwvu   100 W

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Building a water resistant electrical box

Post by Deanwvu » Aug 24 2015 3:40pm

Hello all,

I have a question for the more experienced builders out there...

I'd like to add an electrical box of sorts to my bike. Inside the box I would like:

1. Main power goes in, hot wired to a DC breaker, and that breaker switch is accessible from the outside (this will be a main power cutoff switch).
2. A DC converter (12v) to power all of the 12v stuff on the bike (to power lighting, horn, and a 12v outlet, preferably mounted to the box itself. Do the DC step-down converters get hot?
3. A 12v bus bar to add more 12v accessories as needed.
4. Maybe a switch for all 12v items, so I can disable the 12v accessories.

How do I make this fairly waterproof? Grommets, epoxy? I'd prefer to use a method for which it is not TOO difficult to run more wires later.

What material should I use? Aluminum? Plastic? I can't machine/weld my own, so where to get them? I can drill holes and cutouts for switches, etc.

Thanks!
http://www.endless-sphere.com/forums/vi ... 28&t=70368 My Big Dummy drive by LightningRods.

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fesanand   10 W

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Re: Building a water resistant electrical box

Post by fesanand » Aug 24 2015 4:32pm

I think all of us who has used Pelican Boxes have the duty to enhance its advantages: Resistant, waterproof, theft-proof using the proper lock... easy to work with the dremel... I used to use a 1300 with the battery, circuit breaker and controller inside, but you can always use one of the small models Pelican or unbranded. If you wouldn't like to mount it on the fork I remember someone mounting 2 small boxes on each side of the top tube... just don't have the link.

Punx0r   100 GW

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Re: Building a water resistant electrical box

Post by Punx0r » Aug 24 2015 5:13pm

Have a look at off-the-shelf water proof electrical boxes. If there's one in the size you want it'd save you a lot of work and used with corresponding cable grommets would be reliably waterproof. Don't forget to make a small drain hole at the lowest point.

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Snurt   100 mW

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Re: Building a water resistant electrical box

Post by Snurt » Aug 24 2015 8:56pm

Also cover connectors and exposed components with dielectric grease(like Vaseline).

It will be a 2nd fail safe in case whatever box should leak some.

dnmun   100 GW

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Re: Building a water resistant electrical box

Post by dnmun » Aug 24 2015 9:56pm

why do you need a water resistant box? will it be used under water? you know your controller is not sealed don't you? or the motor. an AC breaker will not work on DC current. it will fuse closed circuit.

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biohazardman   100 kW

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Re: Building a water resistant electrical box

Post by biohazardman » Aug 24 2015 10:49pm

Many if not most small tool/boxes will werq well and they can be inexpensive. A bit of silicone can seal places that need it and wires run from the bottom will not need a full seal. Many panniers and rear rack packs will werq as well The material is water resistant on most and you can spray them, to make them so, if they are not. You can also put ABS or other hard plates of plastic inside the panniers and bags to strengthen them. I have used all three of these, years each, in the rain and nothing inside throttles, controllers, batteries ect got wet. Pelican boxes and boxes like them are great as well. There are so many ways to do this. Take a look at the photos of what others have done.

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Deanwvu   100 W

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Re: Building a water resistant electrical box

Post by Deanwvu » Aug 25 2015 7:17am

dnmun wrote:why do you need a water resistant box? will it be used under water? you know your controller is not sealed don't you? or the motor. an AC breaker will not work on DC current. it will fuse closed circuit.

The term "water resistant" is generally used for splash-proofness, not submersion. Water-proof is the term you are thinking of, which is protection from submersion. As I may be riding in the rain, I want the box to shed water and not take it in.

As I said in the original post:
Deanwvu wrote: 1. Main power goes in, hot wired to a DC breaker, and that breaker switch is accessible from the outside (this will be a main power cutoff switch).
This is a DC breaker, so your comment about AC breakers is helpful (thanks), but not relevant at all.
http://www.endless-sphere.com/forums/vi ... 28&t=70368 My Big Dummy drive by LightningRods.

Deanwvu   100 W

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Re: Building a water resistant electrical box

Post by Deanwvu » Aug 25 2015 7:19am

The rest, of you, thank you for your help! I'll see what I can pull together!
http://www.endless-sphere.com/forums/vi ... 28&t=70368 My Big Dummy drive by LightningRods.

dnmun   100 GW

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Re: Building a water resistant electrical box

Post by dnmun » Aug 25 2015 11:26am

if you used a pelican box like duane then you could ride submerged across a lake like he does.

he is an avid outdoorsman and likes to hunt using the traditional indian techniques of duck hunting by swimming out to them and grabbing them, except he uses his ebike to ride submerged across the bottom of that lake and when he gets underneath the ducks he will grab them from below, break their necks and keep on plucking them until his hamper is full and then he rides on across the lake to his mansion on the other side and feeds his tribe.

so he really knows about how to make them leakproof. follow his advice.

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