Daisy Chains power strips

[QES]

I know a customer that daisy chains their power strips to the 3rd degree and all max out. He was using to runs lamps and other things and running it for 10 hours a day continuously. I think the outlet is running on a 20a ckt. Its has been a year now and the ower told me that the breaker never trip and the fuse on the strips never goes out.

This this even legal?

 

[Pierre C Belarge]

No.
That requirement is located in the UL White Book. I do not have it here, I am in Bob's home state of Mass. My daughter is graduating college this weekend...they are all still asleep, hence I am on my laptop here in my room.

 

[iwire]

No.
That requirement is located in the UL White Book.

Here it is, UL calls them relocatable power taps.

RELOCATABLE POWER TAPS
(XBYS)

USE AND INSTALLATION

This category covers relocatable power taps rated 250 V ac or less, 20 A
or less. They are intended for indoor use as relocatable multiple outlet
extensions of a single branch circuit to supply laboratory equipment,
home workshops, home movie lighting controls, musical instrumentation,
and to provide outlet receptacles for computers, audio and video equipment,
and other equipment. They consist of one attachment plug and a
single length of flexible cord terminated in a single enclosure in which one
or more receptacles are mounted. They may, in addition, be provided with
fuses or other supplementary overcurrent protection, switches, suppression
components and/or indicator lights in any combination, or connections
for cable, communications, telephone and/or antenna.
Relocatable power taps are intended to be directly connected to a permanently
installed branch circuit receptacle. Relocatable power taps are
not intended to be series connected (daisy chained) to other relocatable
power taps or to extension cords.Relocatable power taps are not intended for use at construction sites and
similar locations.
Relocatable power taps are not intended to be permanently secured to
building structures, tables, work benches or similar structures, nor are
they intended to be used as a substitute for fixed wiring. The cords of
relocatable power taps are not intended to be routed through walls, windows,
ceilings, floors or similar openings.
Relocatable power taps have not been investigated and are not intended
for use with general patient care areas or critical patient care areas of
health care facilities as defined in Article 517 of ANSI/NFPA 70, ‘‘National
Electrical Code’’ (NEC).
Component power taps may be factory installed on relocatable equipment
intended for use in general patient care areas or critical patient care
areas as defined in the NEC. They are intended to comply with 60601-1,
‘‘Medical Electrical Equipment, Part 1: General Requirements,’’ and 60601-
1-1, ‘‘Safety Requirements for Medical Electrical Systems.’’ Refer to Medical
Equipment (PIDF).

RELATED PRODUCTS
For relocatable power taps employing cord sets provided with leakage
current detection and interruption, see Cord Sets with Leakage Current
Detection and Interruption (ELGN).
For portable ground-fault circuit interrupters, see Ground-fault Circuit
Interrupters (KCXS).

ADDITIONAL INFORMATION
For additional information, see Electrical Equipment for Use in Ordinary
Locations (AALZ).

REQUIREMENTS
The basic standard used to investigate products in this category is UL
1363, ‘‘Relocatable Power Taps.’’
UL MARK
The Listing Mark of Underwriters Laboratories Inc. on the product is the
only method provided by UL to identify products manufactured under its
Listing and Follow-Up Service. The Listing Mark for these products
includes the UL symbol (as illustrated in the Introduction of this Directory)
together with the word ‘‘LISTED,’’ a control number, and the product
name ‘‘Relocatable Power Tap,’’ ‘‘Power Tap’’ or ‘‘Outlet Strip.’’

The question in my mind is this.

Is there any reason a private citizen has to follow ULs recommendations?

About the only way I see this enforced is when a fire dept inspector inspects a public building and forces the removal of extension cords and plug strips.

I am in Bob's home state of Mass. My daughter is graduating college this weekend...

Welcome to MA, sincere congratulations on your daughters graduation, sorry the weather is so bad.

 

[jaylectricity]

I know a customer that daisy chains their power strips to the 3rd degree and all max out. He was using to runs lamps and other things and running it for 10 hours a day continuously. I think the outlet is running on a 20a ckt. Its has been a year now and the ower told me that the breaker never trip and the fuse on the strips never goes out.

This this even legal?

As long as the first strip in line is plugged into a 16 gauge extension cord! OK, I'm joking.

The legal matter has been discussed, but the actual safety issue is the problem:

If 16 amps get drawn through the last strip in line, then all of the strips would have to be rated for 20 amps, and I would still be concerned about it. Most people who have that many strips don't buy the commercial grade. I just checked the 4 closest to me and they were all rated 15 amps. (all plugged into a different receptacles on the same 15 amp circuit)

IN a similar situation if you have a dedicated receptacle on a 20 amp circuit, that receptacle must be rated for 20 amps. That way the overcurrent device will trip before the amperage exceeds the rating. But if you put more than one receptacle on that circuit you are permitted to use 15 amp receptacles because the circuit is run in parallel and it is more likely the loads will be divided between the multiple receptacles.

That does not happen when you plug strips in end to end because all of the current passes through the first strip. That is compounded by the fact that each strip gives the HO many many places to plug all his stuff. If it starts to add up to >15 amps the first device will start to heat up, which will begin to compromise the insulation and eventually the wires and terminals.

The result: Arc-faults and fire.

Please advice him on the dangers and then try to sell him some new plugs in his room!


edited for spelling

 

[petersonra]

I know a customer that daisy chains their power strips to the 3rd degree and all max out. He was using to runs lamps and other things and running it for 10 hours a day continuously. I think the outlet is running on a 20a ckt. Its has been a year now and the ower told me that the breaker never trip and the fuse on the strips never goes out.

This this even legal?

It is potentially not in accordance with the UL listing and manufacturer's instructions. But in most cases, failure to follow such instructions is not a crime.

If the circuit is not overloaded, it won't trip, no matter how many strips are tied together.

Whether it is safe or not, is another issue. I suspect that in most cases, it does not present any appreciable increase in hazard over not doing so.

 

[QES]

I did try to tell me to remove it, but his answer was " if its not broken why fix it."

 

[kkwong]

Answer: "'Cause if you don't the fire inspector will make you." I get in to that argument a lot with people about daisy chaining not only strip plugs but extension cords as well. QES, depending on where you are in CA, your Fire Dept should have a/an inspector with a complaint line that you can call for code enforcement. That will probably be the best course of action other then having things melt.

 

[charlie b]

I did try to tell him to remove it, but his answer was " if its not broken why fix it."

Perhaps this will help. It's not the first time I've posted this on the Forum, and I don't think it will be the last.

I like to use the following analogy, whenever someone tells me, ?It?s never been a problem before.?

• Suppose that just before you back your car out of the driveway each morning, you put on blinders and earmuffs.

• Suppose that you wait for a random amount of time, and then just back into the street.

• When you get into the street, you can take off the blinders and the earmuffs, and drive to work.

• Question: If you do this ten days in a row, and if you don?t hit anything during those ten days, would you conclude that this is a safe driving habit? Or would it take 20 consecutive days without incident, to convince you it was safe? 30? How many?

Everyone is welcome to steal this analogy shamelessly. But give me authorship credit, if you wish to use the following aphorism:

"An accident waiting for a place to happen will, given time, find that place.? Charlie Beck

 

[petersonra]

Charlie -

You have to know there is a big difference between a blatantly unsafe practice and a practice which is only a violation of some minor rule and not truly unsafe.

 

[infinity]

Charlie -

You have to know there is a big difference between a blatantly unsafe practice and a practice which is only a violation of some minor rule and not truly unsafe.

I agree. I don't see this as a major safety hazard. I must have 5 of those strips plugged together under my desk. My guess is that the total load is less than 5 amps. The first unit has an integral 15 amp CB so I fail to see the danger.

 

[GeorgeB]

I agree. I don't see this as a major safety hazard. I must have 5 of those strips plugged together under my desk. My guess is that the total load is less than 5 amps. The first unit has an integral 15 amp CB so I fail to see the danger.

When you have an OCPD, doesn't this really become the classic "how many receptacles can you have on a circuit" question? I'm not sure how I would feel about an unprotected one as the FIRST inline. Wiremold has the only plug-in of which I'm aware without any OCPD.

 

[charlie b]

You have to know there is a big difference between a blatantly unsafe practice and a practice which is only a violation of some minor rule and not truly unsafe.

Agreed. I was commenting on the notion of ?It?s never been a problem before,? simply because I don?t like to hear that stated as being the reason something ?must be safe.?

Please note, however, that although the original post asserted that nothing has yet tripped, it did not tell us whether or not anything had ever gotten hot to the touch. Something could get hot, and stay hot, and not cause a fire. On the other hand, next week when a piece of paper falls off a table onto the ?safe? hot object, a fire might start. The unsafe aspect of this situation is something might be hot, without that fact being noticed by the homeowner.

 

[QES]

I forgot to add , but all the wires and strips are warm and not hot.

 

[jaylectricity]

Well, I said one thing, but I screwed up...

Quick hide the evidence.