Sanity Check: Building a small power distro?

[aonomus]

I wanted to get some more input before pursuing an idea further, hence why I signed up on the forums finally (long time lurker).

I help handle the AV needs for a once a year small-ish comic convention, and our power needs for the main event hall have grown steadily. Our venue has a pair of L21-30 outlets (and a larger ceeform which costs money to rent the house distro, and is overkill for our needs).

The L21-30 outlets have 208V 3 phase wye power on them (120V L-N), so we could get all our power from those outlets instead of running 6 extension cords across the walls of the room to get our power.

So the question is, should I consider building a power distro using a L21-30 plug, some 10/5 SOOW cord, 6 breakers, a panel, and 3 duplex wired outlets? I do intend to get it inspected and approved by an electrician locally before I use it, but are there any particular pitfalls that I should be weary of? Money is tight, so building a distro for $150-200 and inspection will still cost less than a $500 distro with shipping (into Canada with taxes, duty, and brokerage fees).

 

[MikeJ]

It certainly can be done, If you know what you are doing, but LEX and Motion Labs both make the exact product you need. Many rental houses use them for power distribution, and you may be able to rent a couple each year for only a few bucks.

Also, I find that little expenses on these kind of projects tend to sneak up on you, and $150-200 can easily become $300+

 

[SteveB]

You can certainly build one, but you will be re-inventing the wheel.

Lex Products makes exactly what you are talking about, a 30 amp, 3 pole, 6 receptacle Bento box. I think I paid about $450 for mine

Note that while it shows 3 duplex receptacles, the outlets are split, so ea. is on it's own 15 amp breaker, thus 6 outlets.

http://www.lexproducts.com/products...bento-box-with-tail-input-to-nema-receptacles

 

[Lextech]

Check out Motion Labs. They make great stuff and they have a ETL listing. That means they meet code in the US as well as Canada. I have built a bunch of power distros in my life, and now for liability reasons will not. If you feel that you need someone to check your work, then I really feel that you should not be building your own.

 

[derekleffew]

... Many rental houses use them for power distribution, and you may be able to rent a couple each year for only a few bucks. ...

This!

If it's a once a year need, and budget is tight, renting makes more sense. You don't have to store it, maintain it, and can easily obtain something else if/when your needs change. Yes, you'll pay more in the long run, but the payback to having your own could take several years. As to building your own, the AHJ of the venue is likely to require a Listed, by NRTL sticker (ETL or UL) showing the unit complies with UL1640 standards. Parts sourced from the local home improvement center, no matter who assembles them, are NOT acceptable.

I'd start at Chistie Lites-Toronto (I'm sure there are other appropriate companies of which I'm not aware), and expect to pay $25-50 per week.

 

[MNicolai]

This is all not to mention the incredible amount of liability you are voluntarily, personally taking on if you build your own device.

If anything should go awry (electrical fire within unit or within connected cables/devices, arc flash, electrical damage to connected devices, harm to people as a result of any of the aforementioned incidents), you are unnecessarily inviting potential litigation and even potential criminal charges. Whether or not your home-built unit is the cause or not, you'll quickly find yourself buried in legal fees magnitudes greater than the $200 you might save building your own unit versus renting.

 

[aonomus]

I had considered Christie lights, but the problem is that the particular hotel signed over exclusive rights to the event power service to a particular AV subcontractor (who shal not be named). They only allow the use of their house power service at a steep cost (for us) using their own distro only. The concerns listed in the thread are valid, so for this year's event we'll end up running a fair number of extension cords.

Also it turns out those L21-30's apparently aren't wired in to anything, they're leftovers from an old renovation and were never removed. So the interest in building a distro is dead anyway.

 

[Beans45601]

This advice applies to any question regarding electricity - Chances are, if you have to ask, you should not do it. If it involves 120+ volts, you should not ever do it yourself unless you are *sure* you know what you are doing (aka, are the one giving advice, not the one asking for it)