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Post Info TOPIC: Amps and watts and stuff...


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Amps and watts and stuff...
 


Blowed if all that a/h watts stuff will stick in my brain. I have a stick blender I use for my toothless diet - smoothies and stuff like that. It's a 250 watter. My house battery is an AGM 105ah and the inverter is 300 watt (max 600). If I use the blender once or twice a day for two minutes each time, will the sky fall in?



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Gary

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If the stick draws 250W and your inverter provides 300W (600W max for short periods) you should be OK. We used to test such theories in the Old Navy using The Smoke Test: Fire it up and if it starts smoking, you know it's not feasible (the sky may or may not fall in).

Hope this helps, and Seasons greetings!

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I, also,think you will be ok.Just don,t run it all day. Love the Smoke test, but it can be a little hard on your equipment, and you tend not to be able to use said equipment after trying it out this way.Bill

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Thanks, peeps. I do like my smoothies fresh ya know.

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Hi Gary
Just did the quick maths for you

4min per day x 300W [allowing for conversion losses]divdie by 60 [mins]divide by 12V =0.416665Ahrs per day

PeterQ

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oldtrack123 wrote:


Hi Gary
Just did the quick maths for you

4min per day x 300W [allowing for conversion losses]divdie by 60 [mins]divide by 12V =0.416665Ahrs per day

PeterQ


 So is that a YES or a NO Peter ?????

 

Talk about Baffling everyone with science

Or as we used to say in the RAAF

Bullshxt Baffles Brains...

 

 



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Not hard to see, 4min per day gives .4166 Ahs per day. Less than half an amp hr, not worth worrying about.

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D.L.Bishop


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DeBe wrote:

Not hard to see, 4min per day gives .4166 Ahs per day. Less than half an amp hr, not worth worrying about.


 That part is easy...

BUT

 

I am wondering if the 300w inverter will handle a 250w appliance under load :- Breaking down a banana etc..

I would have been more inclined to go for a bigger inverter so it isn't working close to it's max.. say a 600w/1200w pure sinewave they are almost the same outside dimensions and very little more money if any  but able to handle the load with ease..

Just my opinion...



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oldbobsbus wrote:.

 That part is easy...

BUT

 

I am wondering if the 300w inverter will handle a 250w appliance under load :- Breaking down a banana etc..

I would have been more inclined to go for a bigger inverter so it isn't working close to it's max.. say a 600w/1200w pure sinewave they are almost the same outside dimensions and very little more money if any  but able to handle the load with ease..

Just my opinion...


 

Hi

I am glad it is just your opinion[obviuosly not very well informed on inverters]

It certainly is not MINE

The inverter is rated 300W CONTINIOUS!!

it could probably run 400W for 5<10Minutes

The Stick is rated 250W continious or possible less than continious

So why ,in your opinion should the inverter not be able to cope??

It also hase a surge current rating of 600Wshould be more than able to cope with the start up current of the type  type of motor involved![usually series wound or permanent magnet shunt type] ]

IF the start up Current is a problem WHEN starting under load, there is a simple solution

Just load it AFTER it has started

 Besides THAT, he HAS an inverter [300W cont 600W surge]

, His question was is it ok to use??no

PeterQ

A very definate YES



-- Edited by oldtrack123 on Wednesday 4th of December 2013 04:50:40 PM



-- Edited by oldtrack123 on Wednesday 4th of December 2013 04:53:04 PM



-- Edited by oldtrack123 on Wednesday 4th of December 2013 04:57:12 PM



-- Edited by oldtrack123 on Wednesday 4th of December 2013 05:00:51 PM

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Well, I don't know much about watts and stuff but I do know a thing or two about bananas. I break the banana into sections as it goes into the smoothie mix. Then I give the mix a few quick whizzes on 150W (low speed) just to mash it up a bit, and then about a minute on 250W. However, upgrading the inverter is something I'll probably do at some stage. The one I have came with the rig. Thanks again, fellow GNs.

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Hi Gary
YES, running at low speed is also the answer IF it's start up knocked the inverter, that reduces the start up current as well as the run current

PeterQ

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Gary.. I have to agree with Peter..

I see no issue at all..

the ONLY time that you will run into any issues at all if you have something else running..[On the inverter]

I like the minimalist feel you give off..

And YES watt's. volt's, Amp's and Amp-hours are a Pain..

Juergen

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Then add ice . Yum !!

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Whats out there


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GaryKelly wrote:

Well, I don't know much about watts and stuff but I do know a thing or two about bananas. I break the banana into sections as it goes into the smoothie mix. Then I give the mix a few quick whizzes on 150W (low speed) just to mash it up a bit, and then about a minute on 250W. However, upgrading the inverter is something I'll probably do at some stage. The one I have came with the rig. Thanks again, fellow GNs.


 

Good idea to get a bigger inverter, never know when you may need it to run a tool or something else down the track when you increase your power supply with extra panels. Currently they are pretty cheap and readily available, just like solar panels.

Originally had a 300/600w inverter, now have a couple of pure sine wave 1000w inverters, one as a spare. Not many things you'd take in your van or MH use over 1000/watts continuously, that you'd want to run on battery storage, in my opinion.



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native pepper wrote: 

Good idea to get a bigger inverter, never know when you may need it to run a tool or something else down the track when you increase your power supply with extra panels. Currently they are pretty cheap and readily available, just like solar panels.

Originally had a 300/600w inverter, now have a couple of pure sine wave 1000w inverters, one as a spare. Not many things you'd take in your van or MH use over 1000/watts continuously, that you'd want to run on battery storage, in my opinion.


 

Hi

Just remember that oversized means less efficient in energy use

The energy efficiency is best when running near rated max continious load

Besides THAT he has ONE that is quite suitable for his CURRENT purposes

 

 

PeterQ



-- Edited by oldtrack123 on Thursday 5th of December 2013 04:54:19 PM

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oldtrack123 wrote:

Hi

Just remember that oversized means less efficient in energy use

The energy efficiency is best when running near rated max continious load

Besides THAT he has ONE that is quite suitable for his CURRENT purposes

 

 

PeterQ



-- Edited by oldtrack123 on Thursday 5th of December 2013 04:54:19 PM


 No Doubt you will run a replacement to Gary when his close to the wind inverter burns out no matter where he is  in this vast land of ours Peter,  becoz you advised him that his present one will do the job..

There is NO WAY I would be relying on an inverter that is working at it's near max constant load, or don't you have an inverter in your rig.. I like to know my inverters are doing it easy..

Ohhh and BTW how much extra power would he use if he had a 600w/1200w unit running the same times as the one he now has..

 

Be sure to give Gary your phone number so he can get you to deliver one when he needs it...smile



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Just 2 points that I would make here. 1. Bigger is not necessarily less efficient, many larger inverters have a lower quiescent current and lower running losses than their smaller brethren. 2. Many small inverters, especially modified wave ones, will not effectively run motors with even half the rated continuous wattage of the inverter and can be even worse running some tv sets. My advice would be to get a unit that is rated for at least twice the continuous wattage of what you will be running.

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HI

It seems SOME poster have not read the OP's question

He simply asked could he run his blender stick rated @250W for around 2Mins on HIS CURRENT 300W cont  600W surge rated inverter

He did not ask what else he could run ,either at the same time ,or on their own.!!

JUST his blender!

Now I must admit I,& so have others, not asked the question is HIS inverter a MODIFIED SQUARE WAVE  or pure SINEWAVE??

This is relavent not to the size of the inverter[ which I consider quite ample for the JOB HE HAS ASKED] but due to the effect A MODIFIED SQUARE WAVE , no matter how high it was rated would have on the blender motor

To the OP

You will not do any iimmediate damage to either the blender or the inverter IF iit is a MODIFIED SQUARE WAVE,

BUt the blender may not run smoothly,. depending on the method of speed control ,THAT may not function correctly  & the motor will run hotter than normal. BUT that is a feature of MODIFIED SQUARE INVERTERS ,NOT THE SIZE OF THE INVERTER

If you do ever intend to get another inverter MAKE sure it is PURE SINE WAVE

Size appropriate to your expected loads ,With Ample surge current rating to cope with motor start currents[ depending on type & load at start up ,can be 5<7times actual full load run current]

As I stated earlier  the start up current  of the blender may be too much for the 600W surge rating of the inverter ,in which case it will trip out,NO HARM done to either !!

But starting on a lower speed as you do ,lessens that high start up current!!

I Would stonly suggest you do not panic 

Just try it & see how it goes

Again you cannot damage either unless you stall /overload the blender& do not switch it OFF quickly

 

 

PeterQ



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100% Correct Peter,

Thats why I suggested up ^^^^^^^^^^^ there that Gary would be covering himself by looking at getting a 600w/1200w PURE sinewave inverter..

300w/600w

http://www.ebay.com.au/itm/Pure-Sine-Wave-Power-Inverter-300w-600w-12v-240v-/270859893490?pt=AU_Boat_Parts_Accessories&hash=item3f1081faf2

600w/1200w

http://www.ebay.com.au/itm/Pure-Sine-Wave-Power-Inverter-600w-1200w-12v-240v-/260901149832?pt=AU_Boat_Parts_Accessories&hash=item3cbeeb9c88


Like I said there is very little difference in the price ....



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oldtrack123 wrote:
native pepper wrote: 

Good idea to get a bigger inverter, never know when you may need it to run a tool or something else down the track when you increase your power supply with extra panels. Currently they are pretty cheap and readily available, just like solar panels.

Originally had a 300/600w inverter, now have a couple of pure sine wave 1000w inverters, one as a spare. Not many things you'd take in your van or MH use over 1000/watts continuously, that you'd want to run on battery storage, in my opinion.


 

Hi

Just remember that oversized means less efficient in energy use

The energy efficiency is best when running near rated max continious load

Besides THAT he has ONE that is quite suitable for his CURRENT purposes

 

 

PeterQ



-- Edited by oldtrack123 on Thursday 5th of December 2013 04:54:19 PM


Simply made a suggestion for possible future use, not interested in nit picking, or egofests. Personally would prefer to have excess energy available to use if needed, rather than run electronic equipment at close to maximum. In my understanding and experience, electronics run at near capacity, create more heat and wear on components.

Our first 300w inverter I made from a kit lasted about 10 yearsusing it at about half capacity, when we got more stuff to run at near maximum capacity, it would get hot and finally stopped. The next commercial 300w one also ran hot when near capacity and lasted less than 2 years. Our cheap Chinese built 1000w inverters which we've had for more than 2 years, never gets hot and from my calculations, uses the same if not less power, as less energy is lost in heat dissipation and we now have a 82cm led TV running of the inverter, as well as other things and it never gets any where near as hot as the 300w ones.

I'm not technically that savvy, so asked an electronic engineer before purchasing a bigger one and he told me using higher rated equipment will use more energy at startup, but less during operation as heat lose is very small and components are working well below capacity. It makes logical sense and seems to be that way in operation with all mechanical and electrical equipment.

If I drive our bus at 100klms, which is close to maximum speed, it uses more fuel, runs hotter and increases wear. If I run it at 80-90klm it runs very smooth at much lower temps, uses much less fuel and wear and tear is reduced significantly. The difference in outcomes is very little in performance, time and distance traveled, but wear is dramatically reduced through lower temps and mechanical strain on components. Electronic components are no different, they are all subject to the same laws of physics, I beleive.

 



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Gary hi

Thank you for putting that question up, I liked the answers learning from them that I can run a fan that I have with the inverter which I have, good stuff.

Once again to all. Cheers



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Radar.



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My, my, the lads are getting restless. By the way, my inverter is pure sine.

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Don't forget to add the rum to the smoothy.

Ice cream, a banana and a shot of rum, blend it and "instant troppo"



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Keith
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good answer Gary


heat is the enemy of all electronic equipment and as you say is actually wasted energy.


I would add though there is very likely a point at which "oversize" is too big and does waste energy through inefficiency.


as a rule of thumb (my thumb only) I would look to about 50% spare capacity, maybe 33% if ambient temps were cool enough.


When sizing gensets for hospitals (I know this is OT) we always looked to about 35% oversize including any large startup currents within the allowed load.


frank

-- Edited by KFT on Friday 6th of December 2013 10:14:46 AM

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I hadn't thought about heat in the context of the inverter... although I am aware of heat when I use the blender. Being hand held, I can feel the motor getting warm and I'm careful not to allow it to get too warm. But now that heat generated by the inverter has been mentioned, a small 12V fan has been installed near the inverter. Now I know what it's for... I wasn't sure if it was for the battery or the inverter or both. In the meantime, I suppose I could use the blender on low speed (150W) which takes a little longer but still does the job. That would provide 50% spare capacity. I rather fancy the idea of a dash of rum as well hehe.

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HI
just another point that SOME posters may not understand,that is part of the heat equation with electrics is "DUTY CYCLE} the "ON"[run] time compared to "OFF" time
Depending on design factors, that duty cyclefor most appliances & tools may have to be calculated over as short as 5Mins or up to 30Mins<
The so called SURGE rating of inverters is for a very short time more in seconds!.[3<5]which is realy all a motor or any device with a high start current should require, 

Gary's 2<4Mins run time would be a very LOW duty cycle for an inverter that has a 17% safety margin on it's continious[100% run time] rating for the load in question!!

In fact the inverter could well be running at it's most efficient point, the specs woud /should indicate just what that point is.


THe fact that the blender gets hot could also indicate it is not intended for CONTINIOUS duty
It would overheat long before the inverter!!

Duty cycle is a widely used means of determining electrical ratings for motors, welding machines, tools ,appliances, etc.

Welding macines for Manual arc welding are typical
The macines MAX output may be 200A but it may only be able to do that for short periods like 3Mins in 10Mins without overheating

Even your house wiring is based on similar factors, but in that case referred to as diversity factor[simply because it involves multiple loads]

Again Gary IF your inverter is pure sine wave & the blender starts ok on full speed use it with confidence.
If you have a problem with starting on full sped start it on low speed but do not let it stall THAT will damage the BLENDER ,NO MATTER HOW IT IS SUPPLIED

IF A MODIFIED SQUARE WAVE inverter ,NO MATTER WHAT SIZE, the blender may have problems with speed control [smooth running]& overheating but since it is hand held you would have some indication of when it is getting too hot,

THe same factors applies to ANY other appliance you may wish to use from  inverter s

Many items run quite ok ,on MODIFIED SQUARE WAVE inverters, but which will .is a bit of an unknown[ some lap tops will others will not]

Motors will typical be noisy & run hotter 

Tvs may or may not

THAT IS WHY I ALWAYS recommend a PURE sine wave inverter 

PeterQ



-- Edited by oldtrack123 on Friday 6th of December 2013 12:13:03 PM



-- Edited by oldtrack123 on Friday 6th of December 2013 12:20:21 PM

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Vanderee wrote:

Don't forget to add the rum to the smoothy.

Ice cream, a banana and a shot of rum, blend it and "instant troppo"


 Must be Bundaberg or Capt. Morgan though.....hic

 

Peter



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bugger, i forgot the question.....

Short answer, yes it will work fine.

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I have a 3000 watt ( cont ) inverter and have no issues with blender ! I'm not going out to buy another one !!
Sheesh !

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Gary hi

I was doing quite well learning to make a smoothie, not sure about the rum but would go with brandy, when I was younger mum would make me a egg nog  between my early morning starts and morning tea, well mum runs out of vanilla and goes to the medical cabinet gets the brandy, what a great drink for a 15 year old doing 12 hour days.

Along the way I have grained heaps of understandable information about inverters, once again you to all. Cheers



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