Is my 12 amp microwave damaging the wiring to my 15 amp breaker?

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To get a little off topic.. I always recommend a operating smoke alarm in every bedroom of a residence. There is always a chance for fire from any of multiple sources. When I move into a apt that obviously has older smoke alarms I always buy some battery operated ones and hang them up in addition to whatever is there. Gives me peace of mind that if there is defective wiring or the neighbor smokes or? I still will be warned even if the older smokes don't function.
 
wireman71 said:
... I always recommend a operating smoke alarm in every bedroom of a residence....
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That's a requirement here. New construction requires all smokes to be interconnected. One in each bedroom, and at least one on each level outside the bedrooms. More may be required if the ceilings get real funky.

So a typical 4-BR, 2-story house will require at least 7 smokes.
 
Put an AMP PROBE on the circuit and see what it is drawing. Keep It Simple :smile: If you don't have one you should it is a basic tool for the trade.
 
always spotting the obvious...

always spotting the obvious...

i am a residential apprentice in Chicago. I kno nothing of microwaves (except maybe an old Taxi episode with Danny DeVito straddling his microwave to sterilize himself) This question, however, refers to the appartment in which i reside and have not been granted permission to touch (i am trying very not to 0:) but it is oh so tempting!). My hesitation (and question) stem from my microwave tripping a breaker.

I feel that my innitial question has been answered: I have been foolish to ignore the tripping breaker as an acceptable bother. Yes, the wires are at risk, yes the microwave is a potential danger. And yes, the microwave has been replaced.

No problems yet.
 
i am a residential apprentice in Chicago. I kno nothing of microwaves (except maybe an old Taxi episode with Danny DeVito straddling his microwave to sterilize himself) This question, however, refers to the appartment in which i reside and have not been granted permission to touch (i am trying very not to 0 but it is oh so tempting!). My hesitation (and question) stem from my microwave tripping a breaker.

I feel that my innitial question has been answered: I have been foolish to ignore the tripping breaker as an acceptable bother. Yes, the wires are at risk, yes the microwave is a potential danger. And yes, the microwave has been replaced.

No problems yet.
 
with the microwave drawing 12amps, by code, u would have to have that on a dedicated 15a branch circuit, for a cord and plug connected load (t210-21b2). that table states max amps on a 15a circuit rating to be 12a, is that correct or i'm mistaken? i would say the circuit is overloaded if its an old home or the breakers r faulty.
 
480sparky said:
That's a requirement here. New construction requires all smokes to be interconnected. One in each bedroom, and at least one on each level outside the bedrooms. More may be required if the ceilings get real funky.

So a typical 4-BR, 2-story house will require at least 7 smokes.
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480sparky, (or anyone in IOWA)

Does Iowa have any requirments for licensing electricians currently?

Link says legislation was eneacted in January. Has this taken effect as of yet. I'm gathering info on state electrical requirments.
 
cloudymacleod said:
with the microwave drawing 12amps, by code, u would have to have that on a dedicated 15a branch circuit, for a cord and plug connected load (t210-21b2). that table states max amps on a 15a circuit rating to be 12a, is that correct or i'm mistaken? i would say the circuit is overloaded if its an old home or the breakers r faulty.
Click to expand...

No it would not have to be dedicated (defined as "Branch Circuit Individual"), but it's not bad practice. Table 210-21(B)(2) is very close (if not the same) to 210-23(A)(1) that allows up to 80% load capacity - of circuit rating - of 15/20A circuits that supply 2 or more outlets/receptacles or combinations with lighting outlets.

Notice 210-21(B)(2), "Where connected to a branch circuit supplying two or more receptacles or outlets a [1] receptacle shall not supply a total cord-and-plug-connected load in excess of the maximum specified in Table 210-21(B)(2)." This table does allow a 12A maximum load on a 15A circuit with a 15A device.

Residentially we usually provide a 15A dedicated (individual branch circuit) for microwaves.

You've got a good point with breakers because it's easy to assume the breaker is really a "breaker" but the old one's most likely do not have proper protection. If in doubt old breakers should be changed unless they can be tested.
 
I live in a relatively new house with new appliances. 5-6 years old. About once every three monthes the microwave pops the 15 a breaker it is on. I've put an ammeter on it and have never read more than 10 amps. Either a quirk in the electronics of the microwave or there is something else on this circuit (SABC) that I don't know about. ( House was wired by one of my wealthy competitors ) Panel is right on other side of wall in garage so I only have to walk 10 ft. to reset it.With the infrequency of the breaker tripping and the ease of restoring power and getting my coffee heated up I haven't been inclined to pursue it much farther. It remains a mystery.:smile:
 
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BackInTheHabit said:
480sparky, (or anyone in IOWA)

Does Iowa have any requirments for licensing electricians currently?

Link says legislation was eneacted in January. Has this taken effect as of yet. I'm gathering info on state electrical requirments.
Click to expand...

No. They invoked emergency rules to continue working on all the problems that need to be ironed out. So far, I have only received a letter stating they have accepted my applications, and I am allowed to continue working in the geographic areas that I ply my trade. No license yet, but last I heard they're in the process of buying the computer & software to make that happen.

The wheels of gubbamint turn slowly......
 
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