Electrical expert advice needed re:Surge Protector

Discussion in 'Buying Tips and Advice' started by ski2moro, May 6, 2009.

  1. ski2moro macrumors 6502

    May 3, 2007
    Sorry if I posted this in the incorrect area, but I need some advice.

    I spent time today with HP's Tech Support about a scanner issue. I'm convinced that it is related to HP's inability to write software for the Mac but the Tech had another reason I wanted to bounce around here.

    The HP tech said that the reason my scanner took 7 minutes and 32 seconds to scan a 8X11 piece of paper in B&W at 200 resolution to an image file was that my HP all-in-one was plugged into an surge protector. He told me that all HP printers need to be plugged into the wall directly or else it will not get enough power.

    My BS Detector went off.

    The HP tech told me that when multiple devices, including desk lamps, cordless phones, computers etc., are plugged into the surge protector, each one reduces the amount of power to each device. I asked, Watts? Voltage? Amps? Increased resistance? He said he had no idea, but it was HP's policy to tell everyone to plug into the wall and not a surge protector. He told me that this was the reason the scanner was so slow.

    I really don't want a voltage spike to enter my printer, travel through a USB cable or phone line or network cable and into other electrical devices. That's why I have a surge protector. Or so I thought. I also think I remember something about the power brick regulating the small power fluctuations before it hits the device.

    Can someone clarify this for me?
  2. old-wiz macrumors G3

    Mar 26, 2008
    West Suburban Boston Ma
    While you can overload a surge protector, the HP tech doesn't make any sense to me. If you get less power your device shuts down or goes crazy.

    Unless you're running on ancient electrical, the power draw of most equipment is not that much. An exception might be a laser printer when getting started.
  3. MacBook.Matt macrumors regular

    Apr 1, 2009
    well, test it out. plug your printer into the wall, then try scanning a file. If it takes less than 7 minutes 32 seconds, then it looks like youve found your answer.
  4. Battlefield Fan macrumors 65816

    Battlefield Fan

    Mar 9, 2008
    well last i heard is a power supply for a computer cant reach above ~1800 watts. If computers ever end up coming near to this point they say there will be an issue because thats the max wattage a single wall socket can provide.

    Honestly I dont see you having enough devices to reach this limit.

    Surge protectors are meant to deliver a clean line of power to the devices.

    I too claim BS but as macbook matt said test it yourself.(for actual results try both ways 3 times and then take the average to be fair)
  5. ski2moro thread starter macrumors 6502

    May 3, 2007
    Actually, my question is one of electrical science. Is there some formula that applies that calculates loading on a circuit? I understand that low voltage can cause problems in electrical equipment, but how would I be causing a low voltage situation on the surge protector?

    It just doesn't make sense to me and I'm looking for a scientific explanation for his reasoning.

    I have a 10 year old house with 20 amp service. I have several dedicated outlets in my home office, and I don't believe that anything is wrong here. The HP 7280 all-in-one worked on this circuit until I replaced it a couple of weeks ago due to a paper feed problem.

    This surge protector is powering a cordless phone with power brick, a halogen desk lamp that was off, the printer with brick, and a shredder powered off. I doubt that I have 300 watts on there when everything is on. I don't have lights that dim when a motor starts. It makes no sense to me that the scanner light and the little motor inside the all-in-one would draw enough power to be a problem. Laser printers generate heat, so their power usage is greater, but this is Photosmart inkjet printer/scanner/fax.

    In answer to your question, the test scans were all approximately 7 minutes with the same settings I had used before. Same after reboot. Other settings (scan to iphoto or scan to mail or scan to tif) had similar results in the surge protector or in wall.

    I can work-around this annoying HP scanner problem if I have to, but I would like to know if this surge protector/electrical thing is real.
  6. notjustjay macrumors 603


    Sep 19, 2003
    Canada, eh?
    Got a PC you could use to try scanning? I'd bet dollars to donuts that the scanner will suddenly scan at the correct speed, and at least you'll have narrowed down the problem.
  7. ski2moro thread starter macrumors 6502

    May 3, 2007
    My thinking was so focused on the electrical aspect, I am embarrassed to admit that I didn't test it out on my Bootcamp partition. It scanned the exact same document in about 12 seconds, saved it to My Pictures as a .jpg.

    So, how to handle HP? I have a new All-in-one that is supposed to be Mac compatible, but it isn't. The scanning software just doesn't work as advertised.
  8. AllieNeko macrumors 65816

    Sep 25, 2003
    Total nonsense, just don't tell them it's on a surge protector. You can't have a total of more than 1800W or 2400W (15a or 20a circuit). When you reach that limit you're looking at some voltage drops possibly but mainly overheating wire and the potential of a fire. But none of that should happen before you trip the circuit breaker.

    Surge protectors have their own breaker at their rating - usually 15A (1800W on 120V). It'll trip before you've over loaded it from a safety point of view.

    Ignore the HP guy - he knows and understands nothing and the person writing his script probably understands little more and wrote that in there more from a point of view of devices not powering on. Things become rumor.

    Like if you've ever had Verizon Wireless, reps insist (and honestly believe) that dialing *228 it some magic solution to everything. They say it "updates the list of towers" and "updates the phone's software" - neither is true. It updates the list of NETWORKS. But if you're phone is finding the network at all (it says "Verizon Wireless"), it won't help your reception (though it may get you EV if you are only getting 1x in an EV area - since EV is a separate network). And it won't fix software bugs...
  9. miles01110 macrumors Core


    Jul 24, 2006
    The Ivory Tower (I'm not coming down)
    Power (load) = Voltage * Current
  10. suzmilleson macrumors newbie

    May 11, 2009
    I also was having scanning issues with my C7280 and found it strange that HP tech said must not plug into surge protector. Scanning issue was resolved but I am not sure what to do now with regard to power spikes that are possible as I live in the mid-west where we have electrical storms all the time. If what tech says is true my only option that I can see is to unplug printer when not in use. Was thinking about dedicating an extra surge protector with no other components plugged into it. Anyone have thoughts on that? I recently had a huge static electricity issue in carpeted room during snow season and my husband plugged usb cable into desktop from my old hp C6180 and it apparently fried the scanner/copier feature. So wireless is a partial fix so usb isn't being plugged and unplugged from desktop to laptop but can't fathom not using surge protection on new C7280.
  11. aross99 macrumors 68000


    Dec 17, 2006
    East Lansing, MI
    Just plug the scanner directly into the wall and do some tests. If it doesn't speed up, them call them back and tell them it is still slow...

    if it does speed up, THEN worry about why, and what you can do about it.

    My guess is that it won't make any difference at all...

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