Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Surge Protector Settings

  1. Sep 17, 2009 #1


    User Avatar
    Gold Member

    Hi, all.
    When the company that I worked for went out of business, I obtained a surge protector power bar from it.
    There is no brand name, but it's made in Taiwan. I don't even know if it's meant for full-time usage.
    The label on the back reads exactly thusly (including line spacing, case, and relative character size):

    MODEL TL-660-3
    125V 60HZ 15A 1875W E99662
    800V L-N
    400V L-G AND N-G



    (There's a wide gap between 'location' and '9510' and between 'secs' and 'made in Taiwan', but this text editor keeps ignoring the spaces.)
    There's a UL label with text wrapped around it which reads: '87K9 listed temporary power tap'. Below that is a CSA label with 'LR 61599' under it, and below that is 'TIC'.

    The front has the words 'Protection Indicator' on the corded end, with a red indicator light between them. It's lit as long as the thing is plugged in. Below that is a 2-position rocker switch labelled 'EMI / RFI / Surge'. It's supposed to be illuminated, but it just flickered a couple of times, so I assume that it's a neon bulb near the end of its life. The UL and CSA labels are on either side of it. Below that are 2 phone jacks. The left one says 'FAX/MODEM' and the other is 'PHONE'. Finally, there are 6 grounded outlets. There's what I take to be a reset button on the side near the corded end.

    Now to the questions.
    Is this thing meant to be used as a regular power bar, or is it just some sort of short duty-cycle emergency thing? If it can be used full-time, which position should the rocker switch be in for my computer set-up? Would it be the same if I were to use it for my entertainment system rather than the computers? Finally, what are the phone jacks for? If they weren't labelled separately, I would think that it was a pass-through system, but it looks as if each one is either an 'in' or an 'out', with no partner. :confused:
    Thanks in advance.
  2. jcsd
  3. Oct 7, 2009 #2
    Bumping this to see if anyone can help.
  4. Oct 7, 2009 #3


    User Avatar
    Gold Member

    You probably have an inexpensive power strip with some MOVs in it. They are very common, and they can get ruined with one good surge. Their job is to dump excess voltage to ground so that it doesn't get to your equipment. There may also be a small toroidal coil in there to help filter noise in the line current.

    The phone jacks (in a properly-designed surge protector) should also dump excess voltage to ground. This is important because voltage spikes from lightning strikes can come in on the phone lines and damage your equipment.

    Since we don't know much about your surge protector, it's not possible to say what the light in the rocker switch is telling you. It may be an indicator of the condition of the MOVs, in which case it would be a good thing to know the default indicator state. Is the light supposed to be on when everything is OK, or is it supposed to come on to warn you that the MOVs can no longer handle surges?

    My recommendation would be to go out and buy another surge protector, and if the indicator status, etc isn't marked on the protector, cut the instructions off the packaging and tape it to the bottom of the unit for future reference. I wouldn't trust my electronic equipment to what might have been a $5 throw-in with a computer system.

    I use a belt-and-suspenders approach. My PC gear and fax/copier/printer are plugged into a Cyber-power UPS and that in turn is plugged into a surge protector to help stop large transients from getting to the UPS.
  5. Dec 15, 2009 #4
    It's a standard surge protector, with typical varistor values.

    Computer or entertainment system, hmm, both high-value items... I'd invest in a hardier surge protector. I've had good experiences (ie no failures in spite of lightening strikes that blew incandescent bulbs) with Tripp Lite.

    One thing to look out for, though: The lower the rating, the more likely your equipment is to be protected, but the more likely your surge protect is to blow!


    800V L-N
    400V L-G AND N-G

    Means Line to Negative, and L-G means Line to Ground. Line is also called "Load." It's a dual-phase rating with a neutral ground and a positive L, negative N, with the phases 180 degrees out, so it's not a 120 deg offset tri-phase system. But it's the standard 240/120 system used in the US and fed to most houses in the US.
  6. Dec 15, 2009 #5
    Take a $3 power strip. Add some ten cent protector parts. Sell it at profit for $6 in the grocery store. Or for massive profits at $25 or $150. Same protector circuit. Massive profit margins. Unfortunately, an overwhelming majority will recommend the same protector for more money on myths and irrelevant numbers. Some have recommended a 'better' protector only on myth.

    For example. How many joules in a protector. A few hundred? A thousand? How does that protector absorb surges that are hundreds of thousand of joules? Getting people to ignore numbers is why some will say, "I'd invest in a hardier surge protector." The hardier protector is still near zero protection. View the numbers.

    One recommended only on observation. Observation not tempered by basic knowledge is classic junk science. He observed. He assumed a surge existed on his Tripplite. He had zero reason to believe that (for reasons electrical that I will not explain). And then he just knew. A classic junk science conclusion.

    All appliances contain significant protection. That Tripplite is undersized. A surge that would not destroy that appliance often damages a grossly undersized protection. Then the naive also claim, "My protector sacrificed itself to save my computer". Another example of junk science. And that surge was even too small to harm the Tripplite.

    Effective protector means energy does not even enter the building. NIST (US government research agency) says what the effective protector must do:
    > You cannot really suppress a surge altogether, nor "arrest" it. What these
    > protective devices do is neither suppress nor arrest a surge, but simply
    > divert it to ground, where it can do no harm.

    What does that Tripplite claim to do? Suppress, arrest, stop, or absorb the surge. Total nonsense that gets the naive to assume 'protector' and 'protection' are same. What did the NIST say? Effective protector is a connecting device - it "diverts". Protection is what absorb energy. Two separated devices connected to form a protection 'system'.

    That power strip protector has all but no connection to earth. But earth ground is where energy must be absorbed. A protector, not connected to protection, may even earth that surge destructively via an adjacent appliance.

    Effective protector has a short connection (ie 'less than 10 feet') to central earth ground. As the NIST says, a surge must be diverted "to ground, where it can do no harm." Otherwise energy will be inside the building hunting for earth destructively via appliances. Either energy dissipates harmlessly in earth, OR energy dissipates destructively inside the building.

    Where does a plug-in protector discuss this? A discussion of the always required short connection to earth would harm profits. A majority might then see through the myth.

    How to identify an ineffective protector. 1) It has no dedicated connection for that always required earth ground. 2) Manufacturer avoids all discuss about earthing. 3) Manufacturer specs do not discuss each type of surge and protection from that surge - in numbers. Three reasons why that power strip and that Tripplite do not provide effective protection.

    How do those few hundred joules magically absorb surges that are hundreds of thousands of joules? How does it stop what three miles of sky could not?

    Your telco's computer is connected to overhead wires all over town. Why do they also not use ineffective power strip protectors? About 100 surges exist with each thunderstorm - and no computer damage. Why? For over 100 years, the effective protector is located as close to earth ground as possible. To make that protection even better, the protector is separated from electronics by up to 50 meters. Telcos also do not waste money on those power strip protectors.

    Obviously, an effective protector is only as effective as its earth ground. The answer is always found in a simple question. Where is energy dissipated? Not in a few hundred joules in that power strip.
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook

Similar Threads for Surge Protector Settings
How to set up download from my website?