Forum Discussion

mgirardo's avatar
mgirardo
Explorer
Mar 03, 2017

A new one for me - S&B electrical issue...

This is for the house, not the RV. The wall that our entertainment system (just a computer, DVD player, smart tv & Nintendo Wii for the kids) is a small wall that goes along the stairs to the second floor. There are 2 outlets. On each outlet, the top receptacle is controlled by a wall switch, the bottom receptacle is always on. All electronics on the entertainment center is plugged into a single power strip on one of the bottom receptacles.

We have a small 1500 watt space heater that we use occasionally. I went to use it a few weeks ago and as soon as I plugged it in, there was an arc in the switch, not the receptacle. I've never seen that before. In the receptacle sure, but not the switch. Even though the heater was off, the switch started to spark from the tip of the switch, kind of like an electrostatic generator, except there was nothing near the switch for the electricity to arc to.

It was the strangest thing. I quickly unplugged the heater and thought maybe it was just too much power for the outlet since there was a lot already on them with the entertainment center. However when I went to plug my laptop into one of the top receptacles last night it did it again. There was no arc this time, but fortunately my son noticed that the switch was throwing sparks again, right at the tip. So I unplug the laptop, plugged it into the bottom receptacle and no problem.

Any thoughts what is going on there? Bad switch maybe? Loose wiring at the outlet? I did try a plugin tester and it displayed good. I did not check the voltage at the outlet though.

Thanks,

-Michael

10 Replies

  • wa8yxm's avatar
    wa8yxm
    Explorer III
    Mar 04, 2017
    Good point Happy, I tend to forget hey still make 2-wire cords, you are right.
  • happycamper002's avatar
    happycamper002
    Explorer
    Mar 04, 2017
    wa8yxm wrote:
    . . . Space heaters are typically 1500 watt, about 12.5 amps as I recall without doing the division.. Confirmed by mutliplication.

    Nest there is that good old ROUND hole/pin. the safety ground.
    Recommendation:
    Check heater, an ohmmeter measuring between the flat pins and the round pin may be good enough to find a ground fault. . . .


    With only one problem: not all small space heaters have ground pin, hence, no need for a round hole.

    Most of them are double insulated as in made of plastic.

    All the best.
  • wa8yxm's avatar
    wa8yxm
    Explorer III
    Mar 03, 2017
    Ok some electrical information:

    Space heaters are typically 1500 watt, about 12.5 amps as I recall without doing the division.. Confirmed by mutliplication.

    Outlets are either 15 amp (Two parallel slots) or 15/20 (one slot is "T" shaped)

    Switches can be 5,10,15,20 amp,, 20 amp are rare, even 15 amp are kind of rare

    Nest there is that good old ROUND hole/pin. the safety ground.

    If the heater has a ground fault then that pin may become HOT (Hot to ground short) and this will make the switch box, and the switch itself HOT as well, if there is a break in the safety ground between the switch and the service panel, or a bad connection (SUSPECT #1) in the swich box.. I can see what you saw.

    Recommendation:
    Check heater, an ohmmeter measuring between the flat pins and the round pin may be good enough to find a ground fault, if such exists REPLACE if you do not know how to repair.

    Inspect all connectins in the switch box for signs of arcing, tighten or better yet replace teh switch (Don't take the chance) with a switch rated at least 15, better yet 20 amps from your local hardware or electrical supply Check the box to make sure it can haul the freight.

    ALso do a check to insure a good solid ground,, now this one is tricky. You might want to have someone do it, But what I'd do is make up a 100 watt test lamp...

    The neutral slot is longer than the hot

    Use probes
    Test between HOT and Neutral, notice the brighteness of the lamp
    Test between HOT and GROUND, Same brightness.. GOOD, Dimmer or arcing in the switch box BAD Very Bad.
  • mgirardo's avatar
    mgirardo
    Explorer
    Mar 03, 2017
    There is only one switch operating 1 receptacle on 2 outlets. I'm sure the builder used a cheapest switch they could find. I will get a good quality switch.

    Thanks!

    -Michael
  • enblethen's avatar
    enblethen
    Nomad
    Mar 03, 2017
    Sounds like a three way switch. They are more then KD4LUP posted. Get a good quality back screw type connection type. Look for a 20 amp rated.
  • KD4UPL's avatar
    KD4UPL
    Explorer II
    Mar 03, 2017
    Sounds like a bad switch. The contracts are probably a little burnt and it doesn't like the large load of your heater. The longer you leave it like that the worse it will get.
    A new switch is less than a dollar for a cheap one. A good one is less than $5.
  • troubledwaters's avatar
    troubledwaters
    Nomad
    Mar 03, 2017
    Turn the electricity off, pull the switch out, install a new switch, and make sure all the other wires in the box are not exposed, are tight, and are not touching something they shouldn't be. If this is a 3-way switch (you can turn it on and off from more than one location), make sure you get the black and red wires on just like they were on the old switch.
  • enblethen's avatar
    enblethen
    Nomad
    Mar 03, 2017
    It is called a split receptacle. The jumper on the power side is cut. Two circuits are then run to the receptacle.
    This can be fixed by removing the power wire coming from the switched circuit and a jumper installed between the two brass colored screws.

    Edit;
    You need to verify your switches are not the jab in style. That type has difficulties handling large loads.
  • Johno02's avatar
    Johno02
    Explorer
    Mar 03, 2017
    Call an electrician to check the switch, plugs, and wiring before you burn your house down. Probably overloaded and overheated some wiring.

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