  TimOnTheRoad
@dweavenetworks.net | Daisy chaining power strips
Hey guys, what is the maximum safe number of power strips that can be daisy chained. I've got two and want to add a third but don't want to cause a fire hazard. Thanks. |
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  Rob In Deo speramus, God Bless the USA Premium join:2001-08-25 Kendall, FL
·Comcast
1 edit | The maximum safe number of power strips that can be daisy chained is zero.
Get a larger power strip, but do not daisy chain them. In fact, I believe it's a violation of the National Electrical Code. -- CheckSite.us | YourIP.us | Reverseip.us |
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  Gbcue E.I.T. Premium join:2001-09-30 Santa Rosa, CA clubs:  | reply to TimOnTheRoad Zero. |
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  TearAbite
join:2001-07-25 Rancho Cucamonga, CA | reply to TimOnTheRoad Where i work, if the safety officer catches you daisy chaining power strips you will get a little checkmark next to your name on the safety-list.. |
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  mbaha
join:2009-03-01 | reply to TimOnTheRoad meh just make sure the first one doesn't get tooo hot and your golden -- Don't remind of the things I said or I'll be hurt
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 wolfy339
join:2005-04-30 Edmonds, WA
3 edits | reply to TimOnTheRoad Quoting a flyer on compliance.gov: quote: The supply of readily available electrical outlets is inadequate in some buildings, especially older ones. To meet power supply needs, extension cords or surge protected power strips are often interconnected, or daisy chained, to readily provide more outlets and/or to reach greater distances. Another common solution is to create a mixed daisy chain, interconnecting extension cords and power strips. However, interconnecting these devices is a violation of Occupational Safety and Health Administration (OSHA) regulations and the National Electrical Code because doing so can cause them to become overloaded, leading to their failure and a possible fire. (See the Office of Compliance Extension Cords Fast Facts for more information).
(»www.compliance.gov/forms-pubs/er···ains.pdf)
Thus I have to agree with Rob and Gbcue in saying that the maximum number of powerstrips/surge protectors that can be safely daisy chained is Zero. The obvious concern being that the more power strips you daisy chain the greater the risk that you may go over the rated current capacity of one or more of the strips (or the circuit breaker) or cause one or more of the strips to overheat causing a fire.
-- Computer: PIII/733, 512MB DDR RAM, ATI Xpert2000, 60&320GB HDDs, Windows XP PRO SP3, Mcafee 2009 AV/FW, Creative SB Live, Samsung SyncMaster 2443BWX, Verizon DSL 768/128 w/ Westell 6100 C90 |
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  rawwhide Zer0 Premium join:2000-09-03 Zero clubs:
·AT&T DSL Service
2 edits | reply to mbaha said by mbaha :meh just make sure the first one doesn't get tooo hot and your golden Make sure you don't draw more wattage than is rated for the first one. I would say zero as well. If anything you should use extension cords. |
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  timcuth Braves Fan Premium join:2000-09-18 Pelham, AL clubs:
·AT&T Southeast
| said by rawwhide :said by mbaha :meh just make sure the first one doesn't get tooo hot and your golden Make sure you don't draw more wattage than is rated for the first one. I would say zero as well. If anything you should use extension cords. Or for the outlet the first one is plugged in to. 
Tim -- "Life is like this long line, except at the end there ain't no merry-go-round." - Arthur on The King of Queens ~ Project Hope ~ |
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  psafux Got Grep? VIP join:2005-11-10
| reply to TimOnTheRoad said by TimOnTheRoad :
Hey guys, what is the maximum safe number of power strips that can be daisy chained. Thanks. Ø
-- Yes. the cat in my avatar is indeed mine. |
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 Selenia I'm a PC running Linux, so sue me
join:2006-09-22 Pittsfield, MA
·RoadRunner Cable
·Verizon Online DSL
| reply to TimOnTheRoad Meh. My setup in my study has a daisy chain of 2 not for more outlets, but to have a couple on each side of the room. The first one is a ups with a display that shows my load and I never plug in much. I'd say I'm pretty safe. I just use common sense and also don't invite inspectors over tea, although I had an electrician visit recently who said my setup was more than fine. He was there to evaluate adding more outlets, among a few other things. So no more daisy chaining soon. I did it for years though. |
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  mocycler Premium join:2001-01-22 Naperville, IL
·AT&T U-Verse
·AT&T Midwest
| reply to TimOnTheRoad You should never plug a power strip into a power strip.
But since I know you're probably going to do it anyway, the closest you will get to anything safe is if the whole rig (all the strips and connected devices) does not exceed the current rating of the lowest rated strip.
mocycler |
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 TheMG
join:2007-09-04 Edmonton, AB
·TELUS
1 edit | reply to TimOnTheRoad I must confess that I am guilty of plugging a power strip into another power strip.
I do take precautions to stay on the safe side though:
-purchase only good quality strips rated 15A or more, with 16 AWG wire or better, and with outlets that grip firmly
-strips should have their own circuit breaker built-in, especially if you're using 15A strips and your building has 20A circuits!
-calculate the maximum load all the devices you intend to connect to it will draw in the worst case scenario, an ensure this does not exceed 15A or the rating of the lowest rated strip
One note about the wire gauge, I open up the strips and check them visually. After seeing many cords and strips where the actual wire gauge was much smaller than the rating I am very cautious about it and always check any new strips I buy no matter what the intended usage is.
Stick to that and connected one strip to another is pretty safe, however it remains and always will be a violation of some rule. |
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  John Galt Forward, March Premium join:2004-09-30 Happy Camp
·CenturyLink
| said by TheMG :Stick to that and connected one strip to another is pretty safe, however it remains and always will be a code violation. Actually, it is a violation of its UL listing... -- The man who speaks to you of sacrifice is speaking of slaves and masters, and intends to be the master.
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 wolfy339
join:2005-04-30 Edmonds, WA
| said by John Galt :Actually, it is a violation of its UL listing... Which makes it a code violation, correct? |
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  John Galt Forward, March Premium join:2004-09-30 Happy Camp
·CenturyLink
| said by wolfy339 :said by John Galt :Actually, it is a violation of its UL listing... Which makes it a code violation, correct? No.
It makes it a violation of its listing.
The NEC does not cover "power strips". -- The man who speaks to you of sacrifice is speaking of slaves and masters, and intends to be the master.
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 wolfy339
join:2005-04-30 Edmonds, WA
| said by John Galt :said by wolfy339 :said by John Galt :Actually, it is a violation of its UL listing... Which makes it a code violation, correct? No. It makes it a violation of its listing. The NEC does not cover "power strips". OK so the NEC may not directly cover power strips, but would it not cover using electrical products (including outlets and power strips) in ways that they were not approved for (including ways that violate the UL listing of said product)? Or is there something I am missing/not understanding? -- Computer: PIII/733, 512MB DDR RAM, ATI Xpert2000, 60&320GB HDDs, Windows XP PRO SP3, Mcafee 2009 AV/FW, Creative SB Live, Samsung SyncMaster 2443BWX, Verizon DSL 768/128 w/ Westell 6100 C90 |
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  John Galt Forward, March Premium join:2004-09-30 Happy Camp
·CenturyLink
| said by wolfy339 :Or is there something I am missing/not understanding? The NEC is an installation standard, not a product standard. -- The man who speaks to you of sacrifice is speaking of slaves and masters, and intends to be the master.
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 patcat88
join:2002-04-05 Jamaica, NY
1 edit | reply to TheMG said by TheMG :I must confess that I am guilty of plugging a power strip into another power strip. I do take precautions to stay on the safe side though: -purchase only good quality strips rated 15A or more, with 16 AWG wire or better, and with outlets that grip firmly -strips should have their own circuit breaker built-in, especially if you're using 15A strips and your building has 20A circuits! -calculate the maximum load all the devices you intend to connect to it will draw in the worst case scenario, an ensure this does not exceed 15A or the rating of the lowest rated strip One note about the wire gauge, I open up the strips and check them visually. After seeing many cords and strips where the actual wire gauge was much smaller than the rating I am very cautious about it and always check any new strips I buy no matter what the intended usage is. Stick to that and connected one strip to another is pretty safe, however it remains and always will be a violation of some rule. Always make sure they come with 14 gauge, read the cord. 14 gauge runs cooler than 16. The 16 cord will have a higher temp rating (60C/70C/80C/90C/105C) that can make it run 15 amps, but thats a shortcut and unwise in my opinion. Make sure the power strip has 14 gauge.
Also check for the holographic UL sticker. Look up the number »database.ul.com/cgi-bin/XYV/temp···dex.html
I've found RU computer parts from china, specifically generic ATX power supplies, with "E" UL numbers that don't show up in UL's DB. 
Never plug your power strip into 16 gauge extension cords. Go and throw all you 16 gauge out right now. If you have 18 gauge extension cords (now banned by UL I think), give them to a co-worker you don't like, maybe he will burn down his house . Use orange or air conditioner 14 or 12 gauge extension cords. They might look funny, but they won't melt and run much cooler.
Also make sure your power strip is rated for 15 amps, not 13.
There is also the danger of 15 amp outlets on 20 amp circuits. In businesses, 20 amp outlet circuits are normal. In homes, depends. If the builder is cheap he will put 14 gauge and 15 amp circuits in the walls (except for the kitchen and bathrooms I think). If the builder is good, he will put in 12 gauge and 20 amp circuits in the home. Now there is a danger here, if the power strip doesn't have a circuit breaker ("surge protectors" are rarely circuit breakers), you can pump 20 amps through the power strip, and any extension cord that is feeding the power strip. This can make the 14 gauge extension cords a bit melty/marred or discolored around the plug/socket interfaces. The plug and socket will always heat up before the wire actually does, higher resistance area.
For things like alot of computers, or alot of CE chargers or AV/Home Ent equipment, daisy chaining power strips is inevitable. Its sum of the loads that can make a power strip unsafe, not the number of them daisy chained. The reason power strips are so reviled is because they are usually used in buildings with not enough outlets and circuits. When circuits start tripping, you/DIYers need to install a larger circuit breaker, thats whats broken and causing your power to go off right? Then one day you wake up and night and smell smoke (or your KOed from CO), and see your house is on fire. Then the FD comes, and the TV reporters, and the TV reporters will say its the "evil power strip" that caused the fire, not the homeowner putting a 30 amp breaker on a 14 gauge circuit. If the power strip wasn't there, there couldn't have been a fire there right?......... 
The people who are poor/cheap/greedy are the ones most likely to DIY enhance their power system with larger breakers, daisy chained 16 gauge extension cords through walls (never 12 or 14 gauge extension cords through walls), cube taps, power strips, cords going through doors, abraded wire, vacuum cleaner and chair wheel run over wire, 18 gauge wire powering a window AC.
Here is a genius making the power system better in his home. quote: A single-story home approximately 40 years old was the scene of another fire started by the improper use of an electrical component. This fire began in a bedroom, where an extension cord and a radio power cord were fastened to the wall with nails. The fire investigators concluded that the nails had come in contact with both conductors of the cords so as to form conductive paths that caused over- heating at the contact points between the nails and the wires. A shirt that had been hung on the two nails ignited and dropped to the floor in flames, igniting the mattress and bedding.
»www.cpsc.gov/LIBRARY/FOIA/foia04···rnal.pdf
Some people think, the thinner the wire the better it must be made. If its thin, it must be better wire to buy! Its like a RAZR or MacBook Air. |
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  aurgathor
join:2002-12-01 Lynnwood, WA
| reply to TimOnTheRoad Usually, it's too much current that creates fire hazard, but bad contacts can play an important role, too.
As long as you don't exceed the rating of any single outlet or pair of wire, and the connections are good, you should be OK. (you will probably violate fire codes, though) -- And the winner is: |
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  SirMeowmix_I
@windstream.net
| reply to TimOnTheRoad Be careful. I did this once and the other one went critical and melted. Seriously. Someone was building another computer at a LAN party install Linux and the power strip melted and smelled horrible. I think it was because they were running a dual monitor setup and there was too much current over the 14/2. |
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