(power) Outlet Strips

It turns out the old Waber power strips do what you want. Tripplite bought the company. The photos are awful on the Tripplite website, so you can't see the socket orientation. However here is a decent photo:

Jeff, I like you and I've learned a lot from you over the years. So please accept my constructive criticism in the spirit that it is offered. :)

My fire marshal frowns upon such piggy backed lash ups. You can plug two power strips into a duplex receptacle, or you can plug two cubes into a duplex receptacle, or you can plug one cube and one strip into a duplex receptacle.

You realize this has no basis in reality, right? The connections don't create any real problem. What creates a problem is drawing too much current which lots of outlets on one receptacle can allow. As long as you are plugging in wall warts and not space heaters there won't be a problem.

Not to worry. Over the years, I've developed a calloused exterior, impervious to criticism, constructive or otherwise. I can handle it.

How many of these have you seen?

Yep. It's not legal, but is it really unsafe?

However, the associated NFPA NEC rules make little sense to me. I see no possible way to overload a power strip with nine wall warts that draw between 2 and 15 watts each. Were all the wall warts in the photo 15 watt devices, the total draw would be: 9 * 15 = 135 watts which would never blow the 10amp(?) fuse or breaker on the power strip. In theory, you can load the power strip to just below where the fuse blows. Daisy chaining the power strips should not create an overload because the fuse or breaker in the first power strip should blow when overloaded.

I presented the problem to the local fire marshal at CDF/CalFire: After several months, I received an informal opinion stating that it was unsafe because it presented a configuration that had not been tested by UL. What that means is that it probably won't burn my house or office down, but I can be fined if I get visited by a safety inspector. Swell.

The problem boils down to fused versus unfused power strips. Without the fuse in the first power strip, it is possible to overload the circuit by plugging in a large number of high current devices. Same problem with an extension cord. If you're lucky, the power panel circuit breaker will trip. If you're not, the plastic power strip will melt, start a fire, and ruin your day. A fuse or breaker in the power strip will help prevent that from happening.

Where this affects me is that I have a number of formica lab workbenches in my palatial office. Each has one or more power strips to power test equipment, computahs, monitors, and lights. Although all the power strips on the bench have fuses or breakers, I made an effort not to overload any individual wall jack. However, due to the lack of wall receptacles, there were several power strips connected as a daisy chain. I was not interested in fighting city hall because it was easier to add additional breakers, and several wall outlets, so that each power strip could plug directly into a single wall jack.

I think what you want will require some reconfiguration, at the very least, if not some metal punching on your own.

RL

Hey! Get it BEFORE it's recalled!

RL

Why not plug one strip into another into another into another into ...? By your reasoning, as long as the strip closest to the wall outlet is fused, this should be safe?? (why even need a fuse in the outlet strip? after all, the wall outlet is already fused! :> )

A friend has a shop with outlets along the back (concrete) wall. He's added workbenches along the side walls and thinks he's been real clever bringing power to them by daisychaining outlet strips the entire length of the wall (25 ft or so).

Remember, Code is intended to keep idiots from doing stupid things. "Hey, I've got this neat little adapter that screws into a light socket (A base). I can screw it in to this floor lamp, then, plug this OTHER floor lamp into that -- and screw another adapter into that light, etc. The wall outlet is protected so I'm safe, right? What do you mean 'cord wire gauge'?"

That's why outlets have to be spaced (reasonably) close together, an outlet must exist on every wall bracketed by doorways (keep cords from passing across walkways), kitchen outlets have to be much closer and away from water, etc.

I've got a bunch of fused outlet strips in my office, each one having a cord that finds its way directly to a wall outlet. No way I could plug in everything, otherwise.

OTOH, this makes it relatively easy to disconnect everything when away for an extended length of time, or an electrical storm, etc.

Current project is to set up a large UPS in the garage -- where I can afford the space for oversized batteries -- to handle small loads during extended outages (the little 1.5KVA UPS's don't have enough balls for anything other than ~100W loads for any length of time -- e.g., I think this machine, network modem, monitor are only good for about an hour in an outage)

I never heard of the "Office of compliance".

Reference in the pdf to the NEC are wrong. The NEC does not cover power strips.

UL does. "Relocatable power taps are not intended to be series connected (daisy chained) to other relocatable power taps or to extension cords."

OSHA likely picks up UL listing limitations, although OSHA could have its own rule.

The pdf says "only power strips equipped with internal fuses are acceptable as permanent wiring". UL says they "are not intended to be used as a substitute for fixed wiring". Perhaps the pdf means with fuses the strips can be installed for over 90 days?

UL also says "relocatable power taps are not intended to be permanently secured to building structures, tables, work benches or similar structures". Some strips have holes for such use.

As you point out, if an unfused power strip has 4 - 1400W space heaters plugged into it there just might be a fire hazzard that would not violate the fire marshal's prohibition of daisy-chaining. The rating of the strip and its cord may be far lower than the branch circuit breaker rating.

But daisy-chaining is always unsafe? You are, of course, right that it would be real difficult to cause a problem with wall warts.

Many people could create unsafe conditions with daisy-chaining.

It would be nice if OSHA and fire marshals could recognize that some users are technically competent.

And maybe UL should require overcurrent protection in all power strips.