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-   -   Modern Home Offices (https://www.askmehelpdesk.com/showthread.php?t=42471)

  • Nov 12, 2006, 10:41 PM
    jadiaz
    Modern Home Offices
    Like a lot of modern home offices, my office tends to have a number of electronic devices (e.g multiple computers, monitors, printers, shredders, etc). Only recently have I begun to question the amount of power being drawn by each device.

    My problem being that a few times a day the 15A arc-breaker feeding my home office has been tripping. This problem has been occurring more and more after having replaced the original breaker. I know what you might be thinking... the new breaker can be problematic (Home Depot - Murray Brand).

    Is it possible that I am running too many things on this one circuit? Could the breaker be low quality?

    After summing up the power consumption of some of the main devices on this circuit I came up with this:

    Office:
    computers + monitors = 485 watts
    printers (2 lasers) = 520 watt (both printing) 25W (both sleep mode)
    switches + routers = 12W
    fan = 100W full speed
    fan + light = 165W

    Bathroom:
    45W bulbs x 4 = 180W

    Other room:
    Treadmill (technically requires own 15amp circuit, but not powered most of the time)
    small dorm Refrig:
    radio: 50W


    After calculating an average day I would say I am consuming ~1100-1200W when printing

    15A * 120V = 1800W

    I should be below the threshold, no?

    Could I possibly replace the 15A arc with a 20A arc-breaker to give me more wiggle room?

    Could it be that one fully loaded power strip connected to one wall outlet be too much? Should I spread the gear to the different outlets in the room?


    I apologize if I asked too many questions in one posting :)

    jxd
  • Nov 13, 2006, 03:54 AM
    tkrussell
    No you cannot just change the breaker from a 15 to a 20 without replacing the #14 wire with all #12.

    Spreading the load to other outlets won't work if all the others are on the same circuit.

    What is running when the breaker trips? Could be anything that tries to start, like the fridge, which draws high current when starting, along with what ever is running t that time. The load seems fine, a bit close for a 15 amp breaker, difficult to tell without actually measuring the current of what is running at the time the breaker trips.

    The Arc Fault breaker may be sensing something in any one of the appliances that may be causing nusiance tripping. Since this room is now an office and no longer a bedroom, you can replace the AF CB with a standard breaker to see if that helps.

    Nothing wrong with Murray breakers, thou they may be a bit cheaper, they still work just fine. They are a popular brand, and not connected to Home Depot alone. If the load is about 1100-1200 watts running there should be no problem.

    I reallize this may not be much help. If changing the breaker to a regular breaker does not help, then another circuit may be needed. Or there is a defect in one of the appliances the AFCB is picking up, and is doing it's job.
  • Nov 13, 2006, 07:13 AM
    omzig
    If it's an arc-fault trip, the little indicator window on the breaker should indicate as such. If it trips due to overload the indicator would be blank.
  • Nov 13, 2006, 09:11 AM
    jadiaz
    Quote:

    Originally Posted by jadiaz
    Like a lot of modern home offices, my office tends to have a number of electronic devices (e.g multiple computers, monitors, printers, shredders, etc). Only recently have I begun to question the amount of power being drawn by each device.

    My problem being that a few times a day the 15A arc-breaker feeding my home office has been tripping. This problem has been occurring more and more after having replaced the original breaker. I know what you might be thinking....the new breaker can be problematic (Home Depot - Murray Brand).

    Is it possible that I am running too many things on this one circuit? Could the breaker be low quality?

    After summing up the power consumption of some of the main devices on this circuit I came up with this:

    Office:
    computers + monitors = 485 watts
    printers (2 lasers) = 520 watt (both printing) 25W (both sleep mode)
    switches + routers = 12W
    fan = 100W full speed
    fan + light = 165W

    Bathroom:
    45W bulbs x 4 = 180W

    Other room:
    Treadmill (technically requires own 15amp circuit, but not powered most of the time)
    small dorm Refrig:
    radio: 50W


    After calculating an average day I would say I am consuming ~1100-1200W when printing

    15A * 120V = 1800W

    I should be below the threshold, no?

    Could I possibly replace the 15A arc with a 20A arc-breaker to give me more wiggle room?

    Could it be that one fully loaded power strip connected to one wall outlet be too much? Should I spread the gear to the different outlets in the room?


    I apologize if I asked too many questions in one posting :)

    jxd

    Along with changing out the breaker I recently added two Battery Backup devices, to which I have most of the electronics plugged in. Could it be that the BB's are simulating a short when the devices power up?

    What would be the easiest way to measure the current drawn?
  • Nov 13, 2006, 07:18 PM
    tkrussell
    Good info omzig offered to help deterimine the cause of the tripping.

    The UPS units should not be causing a short, but do add to the load a bit along with the appliances/equipment they serve.

    Need a clamp on type RMS AC current meter to measure the amp load.

    If it is tripping due to an arc, can be a switch making and breaking, like the tstat in the fridge, inductive loads make a decent arc when turned on and off. Or a loose or damaged appliance cord.

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