# Is it wrong to mix wattages (light bulbs) in fixtures? **URL:** \ **Category:** Factual Questions\ **Created:** [July 17, 2014, 10:57pm UTC](https://boards.straightdope.com/t/is-it-wrong-to-mix-wattages-light-bulbs-in-fixtures/693413 "2014-07-17T22:57:39Z")\ **Posts on this page:** 15\ **Page:** 1
**Author:** ![dougie\_monty](https://avatars.discourse-cdn.com/v4/letter/d/439d5e/32.png) [@dougie\_monty](https://boards.straightdope.com/u/dougie_monty)\ **Post date:** [July 17, 2014, 10:57pm UTC](https://boards.straightdope.com/t/is-it-wrong-to-mix-wattages-light-bulbs-in-fixtures/693413/1 "2014-07-17T22:57:39Z")
Several years ago, I installed a new ceiling light fixture in the dining room. One bulb recently went out, and I swiped an incandescent bulb from another lamp because this fixture’s brightness is adjusted with a dial, and the new-fangled coil - shaped bulbs don’t work that way. But I had a 100 - watt and a 70 - watt bulb in the fixture–until I replaced them the other day with two 60’s. Is such mismatch dangerous? ---
**Author:** ![beowulff](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/beowulff/32/542_2.png) [@beowulff](https://boards.straightdope.com/u/beowulff)\ **Post date:** [July 17, 2014, 11:13pm UTC](https://boards.straightdope.com/t/is-it-wrong-to-mix-wattages-light-bulbs-in-fixtures/693413/2 "2014-07-17T23:13:04Z")
As long as you don’t exceed the maximum wattage for the fixture (and for each socket), no. ---
**Author:** ![jtur88](https://avatars.discourse-cdn.com/v4/letter/j/e9c0ed/32.png) [@jtur88](https://boards.straightdope.com/u/jtur88)\ **Post date:** [July 18, 2014, 3:30am UTC](https://boards.straightdope.com/t/is-it-wrong-to-mix-wattages-light-bulbs-in-fixtures/693413/3 "2014-07-18T03:30:02Z")
They are two separate lamps, controlled by the same switch. ---
**Author:** ![48Willys](https://avatars.discourse-cdn.com/v4/letter/4/db5fbb/32.png) [@48Willys](https://boards.straightdope.com/u/48Willys)\ **Post date:** [July 18, 2014, 7:02am UTC](https://boards.straightdope.com/t/is-it-wrong-to-mix-wattages-light-bulbs-in-fixtures/693413/4 "2014-07-18T07:02:31Z")
> [@beowulff](#): > > As long as you don’t exceed the maximum wattage for the fixture (and for each socket), no. As a safety issue and NOT a nitpick, I will add not to exceed the wattage rating of the switch as well. OK, OK, the wiring itself must not have its wattage rating exceeded as well. I would ASSuME that the electrician that installed the curcuit knew his/her stuff. A safe bet in my home. Your home may be different. IHTH, 48. ---
**Author:** ![dougie\_monty](https://avatars.discourse-cdn.com/v4/letter/d/439d5e/32.png) [@dougie\_monty](https://boards.straightdope.com/u/dougie_monty)\ **Post date:** [July 18, 2014, 4:04pm UTC](https://boards.straightdope.com/t/is-it-wrong-to-mix-wattages-light-bulbs-in-fixtures/693413/5 "2014-07-18T16:04:29Z")
I live in a mobile home built about 1960. ---
**Author:** ![48Willys](https://avatars.discourse-cdn.com/v4/letter/4/db5fbb/32.png) [@48Willys](https://boards.straightdope.com/u/48Willys)\ **Post date:** [July 19, 2014, 8:25am UTC](https://boards.straightdope.com/t/is-it-wrong-to-mix-wattages-light-bulbs-in-fixtures/693413/6 "2014-07-19T08:25:11Z")
dougie\_monty Said; “I live in a mobile home built about 1960.” Now that changes things. Mobil homes built before 1990 are notorious for having bad wiring. If you doubt me, ask your local Fire Marshall. If it were my home, I would have a licensed electrician look over my wiring. Do your lights dim when either the refrigerator, or the washing machine motor comes on? If so, call sooner rather then later! Do all of your light switches and outlets work properly? In other words do you have quirky things going on with the electrical system? Like the outlet in the 2nd bedroom, hidden by the bed, only works for things plugged in to the top portion of the outlet. If so, Call the electrician. On another note, How big are your house mains? 60 amp? Anything less then 125 amp, IMHO, is too small. With all of the electric and electronic things that we have these days, that were not even dreamed of in 1960, your house’s electrical system is probably overloaded. Are you using any of those six-plex plug adapters? You know, the kind that make a regular 2 plug outlet into a six plug outlet. Are you using extension cords for continuous (not temporary) electrical supply? The TV perhaps? Also your outlets may not even have a grounding lug on them. If not, See your electrician soon! I am not trying to be a bummer, I just want you and your family to stick around for awhile. IHTH, 48. PS. For some reason my computer is not recognizing “Quotes” today. ---
**Author:** ![dougie\_monty](https://avatars.discourse-cdn.com/v4/letter/d/439d5e/32.png) [@dougie\_monty](https://boards.straightdope.com/u/dougie_monty)\ **Post date:** [July 19, 2014, 3:26pm UTC](https://boards.straightdope.com/t/is-it-wrong-to-mix-wattages-light-bulbs-in-fixtures/693413/7 "2014-07-19T15:26:40Z")
Our electrical stuff includes a modern (2013) refrigerator, three TVs (two are small; we rarely have more than one switched on at a time); a microwave oven; my computer setup; several electric clocks; and quite a few lamps. I also have an oil - filled room heater (1875 watts), and we have electric fans for the summer. We had to have one circuit serviced shortly after 9/11 (we had lived here 14 years by then), and one line inside a wall in my room is out --either that or I made a mistake connecting it to a new wall switch I installed. Its outlet doesn’t work. ---
**Author:** ![zoid](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/zoid/32/336_2.png) [@zoid](https://boards.straightdope.com/u/zoid)\ **Post date:** [July 19, 2014, 4:32pm UTC](https://boards.straightdope.com/t/is-it-wrong-to-mix-wattages-light-bulbs-in-fixtures/693413/8 "2014-07-19T16:32:39Z")
> [@jtur88](#): > > They are two separate lamps, controlled by the same switch. Not sure what you mean here. It sure sounds like they’re on the same circuit, not two circuits wired to the same switch. ---
**Author:** ![48Willys](https://avatars.discourse-cdn.com/v4/letter/4/db5fbb/32.png) [@48Willys](https://boards.straightdope.com/u/48Willys)\ **Post date:** [July 20, 2014, 8:16am UTC](https://boards.straightdope.com/t/is-it-wrong-to-mix-wattages-light-bulbs-in-fixtures/693413/9 "2014-07-20T08:16:30Z")
> [@dougie\_monty](#): > > Our electrical stuff includes a modern (2013) refrigerator, three TVs (two are small; we rarely have more than one switched on at a time); a microwave oven; my computer setup; several electric clocks; and quite a few lamps. I also have an oil - filled room heater (1875 watts), and we have electric fans for the summer. We had to have one circuit serviced shortly after 9/11 (we had lived here 14 years by then), and one line inside a wall in my room is out --either that or I made a mistake connecting it to a new wall switch I installed. Its outlet doesn’t work. If it were my house, a call would be made to a licensed electrician, today, OK, Monday. This lack of power to an outlet in a trailer home built 54 years ago is one of the signs of a failing system. Around here it would not cost over $200.00 for an inspection by a licensed electrician. I consider this to be cheap insurance. Most electricians would take the cost of the inspection off of the bill if you decide to have them repair or replace any part of the electrical system in your home. You do not use as much electricity as most folk do. That heater does draw around 17 amps. Not too bad, unless you have several other things plugged into the same circuit. I am assuming that it is on a 20 amp curcuit. If it is on a 15 amp curcuit, you are overloading this curcuit when you use the heater. Do you have a circuit breaker panel, or a fuse box? Do your outlets have two or three prongs? What size are your main breakers or fuses? 60Amp? I doubt if you have any aluminium wire in your home. It was only used in the 70s through the early 90s. Please look into the non-working outlet. Also look into the fusebox/circuit breaker panal issue. A fuse box is NOT ideal. The two prong outlets are less then ideal as well. IHTH, 48. ---
**Author:** ![dougie\_monty](https://avatars.discourse-cdn.com/v4/letter/d/439d5e/32.png) [@dougie\_monty](https://boards.straightdope.com/u/dougie_monty)\ **Post date:** [July 20, 2014, 3:41pm UTC](https://boards.straightdope.com/t/is-it-wrong-to-mix-wattages-light-bulbs-in-fixtures/693413/10 "2014-07-20T15:41:07Z")
The heater is used only in cold weather, and for a few hours at a time. When used, it shares a wall outlet with a table lamp, an electric clock, and a mechanism for adjusting my hospital-type bed. The instructions for the heater say not to leave the heater unattended. As for the outlets, they are all hole in my room, which is really the den–it’s a "double - wide. "… Also, not only do we have circuit breakers, but my room has a pair of second - level circuit - breakers as well. I don’t know their capacity offhand. ---
**Author:** ![dougie\_monty](https://avatars.discourse-cdn.com/v4/letter/d/439d5e/32.png) [@dougie\_monty](https://boards.straightdope.com/u/dougie_monty)\ **Post date:** [July 20, 2014, 3:48pm UTC](https://boards.straightdope.com/t/is-it-wrong-to-mix-wattages-light-bulbs-in-fixtures/693413/11 "2014-07-20T15:48:34Z")
That should be: all the outlets are 3-hole. ---
**Author:** ![48Willys](https://avatars.discourse-cdn.com/v4/letter/4/db5fbb/32.png) [@48Willys](https://boards.straightdope.com/u/48Willys)\ **Post date:** [July 21, 2014, 7:28am UTC](https://boards.straightdope.com/t/is-it-wrong-to-mix-wattages-light-bulbs-in-fixtures/693413/12 "2014-07-21T07:28:34Z")
> [@dougie\_monty](#): > > The heater is used only in cold weather, and for a few hours at a time. When used, it shares a wall outlet with a table lamp, an electric clock, and a mechanism for adjusting my hospital-type bed. The instructions for the heater say not to leave the heater unattended. As for the outlets, they are all hole in my room, which is really the den–it’s a "double - wide. "… Also, not only do we have circuit breakers, but my room has a pair of second - level circuit - breakers as well. I don’t know their capacity offhand. It sounds to me likely that the second-level circuit breakers were installed by an electrician. If so, you should be OK. I would try to remember to not adjust the bed while the heater is on. They both use over 15 amps. I doubt if this circuit is rated at 30 amps. Although it is possible, especially if the electrician was told about the heater and the bed. I had assumed that you would only use the heater in the winter. I am glad to hear that your outlets are all three prong. My worry factor just went down a bunch. Have a good day, 48. ---
**Author:** ![dougie\_monty](https://avatars.discourse-cdn.com/v4/letter/d/439d5e/32.png) [@dougie\_monty](https://boards.straightdope.com/u/dougie_monty)\ **Post date:** [July 21, 2014, 2:25pm UTC](https://boards.straightdope.com/t/is-it-wrong-to-mix-wattages-light-bulbs-in-fixtures/693413/13 "2014-07-21T14:25:11Z")
> [@48Willys](#): > > It sounds to me likely that the second-level circuit breakers were installed by an electrician. If so, you should be OK. I would try to remember to not adjust the bed while the heater is on. They both use over 15 amps. I doubt if this circuit is rated at 30 amps. Although it is possible, especially if the electrician was told about the heater and the bed. > > I had assumed that you would only use the heater in the winter. > > I am glad to hear that your outlets are all three prong. My worry factor just went down a bunch. > > Have a good day, 48. 48?😕 ---
**Author:** ![chorpler](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/chorpler/32/2888_2.png) [@chorpler](https://boards.straightdope.com/u/chorpler)\ **Post date:** [July 21, 2014, 2:32pm UTC](https://boards.straightdope.com/t/is-it-wrong-to-mix-wattages-light-bulbs-in-fixtures/693413/14 "2014-07-21T14:32:10Z")
> [@dougie\_monty](#): > > 48?😕 He is signing his message with an abbreviation of his username ( **48Willys** ). ---
**Author:** ![dougie\_monty](https://avatars.discourse-cdn.com/v4/letter/d/439d5e/32.png) [@dougie\_monty](https://boards.straightdope.com/u/dougie_monty)\ **Post date:** [July 21, 2014, 3:31pm UTC](https://boards.straightdope.com/t/is-it-wrong-to-mix-wattages-light-bulbs-in-fixtures/693413/15 "2014-07-21T15:31:05Z")
Oh.