Microwave consumption ?

[Topmast]

Hi Everyone.
As I understand it microwave ovens use a lot more power on start up than they do while running, So how do you know say on one advertised as being 900 watts how much the start up would be?
I hope this makes sense. Any replies appreciated. Thanks.

 

[Robmac]

Scroll down to FAQ's

Understanding Microwave Wattage: Power, Usage & Costs | EcoFlow ES

Discover how microwave wattage affects cooking speed, energy use, and costs. Learn about wattage ranges, efficient usage tips, and power stability solutions for your kitchen.

www.ecoflow.com

 

[TJBi]

Scroll down to FAQ's

Understanding Microwave Wattage: Power, Usage & Costs | EcoFlow ES

Discover how microwave wattage affects cooking speed, energy use, and costs. Learn about wattage ranges, efficient usage tips, and power stability solutions for your kitchen.

www.ecoflow.com

That link appears to be based upon input and output wattage being the same, but that is not the case. Microwaves are normally rated, for commercial and cooking instruction purposes, according to their output wattage

https://www.justanswer.com/appliance/b5urg-recipe-says-microwave-high-min-or-10min.html#:~:text=Microwave%20Wattage%20Explained:%20Input%20Power,on%20JustAnswer%20before%20making%20decisions.

https://www.quora.com/Is-the-wattage-of-a-microwave-the-input-or-the-output#:~:text=Here's%20some%20information%20about%20input%20and%20output,something%20to%20measure%20the%20amount%20of%20water

 

[wildebus]

Hi Everyone.
As I understand it microwave ovens use a lot more power on start up than they do while running, So how do you know say on one advertised as being 900 watts how much the start up would be?
I hope this makes sense. Any replies appreciated. Thanks.

I've seen this said lots of times, but I have never observed this on any microwaves I have had.
I wonder if people confuse the way the power goes on and off with a 'start-up' power? If you have say a 900W microwave and you set it at 600W, the microwave will usually be at full power for 2/3rds the the time and off for 1/3rd the time to give an average of 600W. (the same pattern can be seen when using an Induction Hob where you can see liquid bubbling and then stop bubbling on an off-off cycle).
There are some microwaves that actually lower the power and stay running at the lower power all the time, but they are rare.

Now to find out how much the microwave draws on full power, there should be a label on the back that has the Input power (as opposed to the 'cooking' power, which is what the 900W would be). Typically the Input power is around 1.3 x the Cooking power, but it does vary between microwaves. My current microwave is an 800W model and has an input power of 1050W. My previous one was also an 800W model but had an input power of 1150W.
You could also put a Watt-meter on the socket and plug the microwave into that and see what it shows for a more exact number. Available on Amazon for around a tenner.

 

[Wooie1958]

My factory fitted 700 watt microwave had 900 watt input power.

 

[mistericeman]

They're usually advertised by cooking power...

You'll need to read the specs/label to discover the imput power...

Bear in mind a 900w (cooking power) will use the same amount of power from your batteries to heat the same item of food as a 1800w cooking power....
It'll just take roughly twice the amount of time.

You'll need a fairly chonky inverter/leads to run even a 900w version....
We had a 3000w/6000w peak inverter that coped fine for limited usage.

 

[Topmast]

Thanks everyone , I am now totally confused ,the reason for asking was if using a say 800 watts oven what size generator would be needed to overcome the start up? If I am understanding the answers correctly there should be be a label stating cooking power .

 

[mistericeman]

Thanks everyone , I am now totally confused ,the reason for asking was if using a say 800 watts oven what size generator would be needed to overcome the start up? If I am understanding the answers correctly there should be be a label stating cooking power .

Usually on the rear.....

Or Google the make/model for specs

 

[wildebus]

Thanks everyone , I am now totally confused ,the reason for asking was if using a say 800 watts oven what size generator would be needed to overcome the start up? If I am understanding the answers correctly there should be be a label stating cooking power .

That is if you believe there is a "start up" to overcome....

You mean a label stating "input power". Cooking power is quoted up front in the description. I replied before telling you where to find the input power.

.....You'll need a fairly chonky inverter/leads to run even a 900w version....
We had a 3000w/6000w peak inverter that coped fine for limited usage.

Not really. I run my 800W (cooking power) inverter just fine on my 1350W Inverter.

 

[Topmast]

Thanks everyone for your imput , I always find electric problems confusing.

 

[Trotter]

Thanks everyone for your imput , I always find electric problems confusing.

You are not alone.

 

[trevskoda]

Thanks everyone for your imput , I always find electric problems confusing.

Others its a way of life.

 

[myvanwy]

I spent 30 plus years repairing motors, transformers etc. The problem is, any appliance that needs magnetism to work, has inductance. This is where an inrush of current (amps) is needed to power the hardware. Once the mag field is up and running, current drops off. eg, an absorption fridge uses a heating element (wire) and a compressor fridge a motor. The former has no inductance and the latter has lots on start up. A microwave has a huge transformer inside. No getting away from that at the mo.