Replace microwave convection oven

Gazelle05 wrote:
Looking for advice I want to replace my sharp 850 watt convection microwave with a 1700 watt oven. Anybody know if the circuit is strong enough to carry the load with out tripping out. Also I can't find the circuit thought it would be on a circuit breaker but it is not. Any ideas as to where the power supply might be coming from would be helpful. Thanks for any and all advice.
Hope your new year rings many a good mile.
2005 Safari Gazelle

Most likely it's a 20amp circuit and should be private, so not a factor. Even a 15 should hold it. It's definitely on a circuit breaker somewhere and if it has something else on it, for loading it down, then you may have to run one thing, at a time.

I had the Sharp 59 second problem about 10 years ago and got the switch replaced. Cured the problem.

My real problem was getting the microwave dismounted. Monaco ran four screws into the top of the unit through the bottom of the cabinet overtop the microwave.

Then they put a shelf over the screws and STAPLED it to the bottom.

So I had to pull the staples, remove the flooring and then unscrew the screws. There are also two very long bolts, 18" maybe, that run from the bottom front of the unit to the top back of the unit.

Do not attempt to remove the microwave by yourself. It is very heavy and bulky.

Hi Doug,

I've checked MANY specs plates on toasters and other electrical items. They are almost never correct. They are usually "in the ball park". It is pretty hard to misread a digital display which is what the kill-a-watt and the Elite monitors use.

I do know that the microwave draws more power than the air conditioner based on the rpm of the Yamaha generator.

The reason for checking is that I want the lowest wattage device that will meet my needs. I did not think to check amps when making selections for small items as all I needed was the lowest figure.

Pianotuna.

Sorry, but either all 3 are wrong or you do not know how to read them. Also, maybe your MW is defective and is pulling higher watts/amps. WHY would you continue to argue with a Spec Plate? They are exact, not a suggestion. Doug

PS, I read AMPS not watts. With amps I convert to watts.

The kill-a-watt agrees with a fluke meter. It also agrees with my Elite watt meter. I think it is unlikely that all three are wrong by 50%.

dougrainer wrote:

pianotuna wrote:
dougrainer,

You can quote the box if you so wish. I was measuring ONLY the microwave and it was 1591 watts. It may be that I have an obsolete model. But the fact remains that it was drawing 1591 watts. I don't have a meter that measures surge or power factor.

You need to think about this. Your Meter was reading TWICE the watt draw. That means your meter is NOT accurate. Sorry, but the BOX serial plate is accurate. Your meter is not. Doug

Well known Sharp MW issue. There is a Sharp Tech Bulletin that indicates the problem is a bad damper switch or damper motor.

Here's a thread about it: Sharp oven 59 sec shut off.

Here's the Tech Bulletin: Oven Tech Bulletin

I understand that the parts are 'improved' so don't fail as often.

The 59 seconds problem is a KNOWN issue by the various Microwave makers. I do not know what part they replace, but it IS a simple diag and replacement part issue. Doug

Gazelle05 wrote:
Thanks for all the helpful info. My coach Sharp 750 watt convection/microwave has been in the shop twice for repairs,not going back for third visit. Works for 59 seconds and shuts down. After following your suggestions as to the power supply I found out it is powered through one 20 amp breaker from my 2000 watt inverter. My choice for replacing the unit is a Samsung Model MC17J8000CS on sale at Home Depot Reg $499. Now $388. Features Convection,Toaster,Broiler,Microwave & Slim Fry Technology. It draws 1700 watts. My math tells me that is 14.78 amps with a 20amp breaker at 80% give me 16 amps available. I am going with that unless anybody can show me where it won't work. Do not want to blow breakers or overheat wiring.
Thanks as usual you guys are the best.

A microwave oven is not a continuous load, as defined in the NEC, and so does not require the 80% derating. The oven would be okay on a 15A circuit. (It better be, as it seems to have a regular 15A plug on the cord.) The manual for it indeed states "The microwave requires a separate branch circuit single grounded outlet of at least 15A and max of 20A."

In short, you should be fine with it, assuming you don't have much if anything else running on the inverter at the same time.

Thanks for all the helpful info. My coach Sharp 750 watt convection/microwave has been in the shop twice for repairs,not going back for third visit. Works for 59 seconds and shuts down. After following your suggestions as to the power supply I found out it is powered through one 20 amp breaker from my 2000 watt inverter. My choice for replacing the unit is a Samsung Model MC17J8000CS on sale at Home Depot Reg $499. Now $388. Features Convection,Toaster,Broiler,Microwave & Slim Fry Technology. It draws 1700 watts. My math tells me that is 14.78 amps with a 20amp breaker at 80% give me 16 amps available. I am going with that unless anybody can show me where it won't work. Do not want to blow breakers or overheat wiring.
Thanks as usual you guys are the best.

pianotuna wrote:
dougrainer,

You can quote the box if you so wish. I was measuring ONLY the microwave and it was 1591 watts. It may be that I have an obsolete model. But the fact remains that it was drawing 1591 watts. I don't have a meter that measures surge or power factor.

You need to think about this. Your Meter was reading TWICE the watt draw. That means your meter is NOT accurate. Sorry, but the BOX serial plate is accurate. Your meter is not. Doug