Inverters, Sine Wave?

Submitted: Tuesday, Aug 03, 2004 at 14:12
ThreadID: 15259 Views:3981 Replies:6 FollowUps:14
This Thread has been Archived
I was up the bush a couple of weeks ago and took a number of digital shots and then hooked up the flip top to view and edit them, via a $70 Dick Smith 150 watt inverter and it worked a treat.

I've read in advertising material about the need for a "pure sine wave" inverter to run electronic equipment. What is the merit, if any, to this?

Has anyone damaged equipment using an "impure" inverter?
Back Expand Un-Read 0 Moderator

Reply By: Baz (NSW) - Tuesday, Aug 03, 2004 at 14:39

Tuesday, Aug 03, 2004 at 14:39
Hey Jimbo, pure sine wave is for delicate electrical equipment (eg) medical equip, scientific equip, modified is OK for most other items.

Baz.
AnswerID: 71070

Follow Up By: Member - Jimbo (VIC) - Tuesday, Aug 03, 2004 at 14:48

Tuesday, Aug 03, 2004 at 14:48
Thanks Baz'

I assume from that a fliptop is not considered delicate?
0
FollowupID: 331289

Follow Up By: Vince NSW - Tuesday, Aug 03, 2004 at 14:50

Tuesday, Aug 03, 2004 at 14:50
Can't be Jimbo, Mine has survived me using it
Vince
0
FollowupID: 331294

Follow Up By: Baz (NSW) - Tuesday, Aug 03, 2004 at 14:53

Tuesday, Aug 03, 2004 at 14:53
Yeah i'd say so, we have two inverters 1 pure for Nessie's nebulizer and 1 for charging laptop and camera's.
0
FollowupID: 331295

Follow Up By: Member - Jeff M (WA) - Tuesday, Aug 03, 2004 at 15:04

Tuesday, Aug 03, 2004 at 15:04
That dick smith inverter is not a "modified sinewave" it's a square wave, I have the same one. Yeah it'll work, however it will eventually damage the power supply if it's a switch mode (which a notebook supply is). I do use my inverter to charge my video camera (which I shouldn't) and it works fine, but one day it will pop it. I just put it on when I really need it.
For $79 you could have bought a laptop 12v power supply from Jaycar that will be much more efficnat and won't damage anything.

www.jaycar.com.au

They run from 15v to 24v. They have power adaptors to suit almost all laptops complete with them. You can then hardaire the supply into your 12v system and just have the plug there ready to hook the notebook up when you need it.
0
FollowupID: 331300

Follow Up By: Bonz (Vic) - Tuesday, Aug 03, 2004 at 17:32

Tuesday, Aug 03, 2004 at 17:32
Jimbo, The "delicate" piece of equipment is the charger not the laptop/notebook computer. Most of these little things will handle square wave inverters no problems as they have internal circuitry that copes with a range of different input waveforms and produce the DC at the other end.
.
Time is an illusion produced by the passage of history
.

Lifetime Member
My Profile  My Blog  My Position  Send Message
Moderator

0
FollowupID: 331316

Follow Up By: Member - Jeff M (WA) - Tuesday, Aug 03, 2004 at 17:35

Tuesday, Aug 03, 2004 at 17:35
Bonz, what is this circutry that copes with different input waveforms?? My geek of a brother told me it's a standard switch mode power supply that will die with constant square wave "abuse".
0
FollowupID: 331318

Follow Up By: Bonz (Vic) - Tuesday, Aug 03, 2004 at 17:55

Tuesday, Aug 03, 2004 at 17:55
Its one of them Jeff, but they'll cope for ages with a little square wave, and for longer with modified sine wave (which is what I would go for anyway). If you are planning on running all the time with the inverter then go for the sine wave, otherwise even with a little abuse the power supply will probably outlast the laptop. Anyways if it does cack itself theyre only $50-$80 to replace, and thats less than the difference between the sine and modified sine wave anyway.

I had a modified sine wave inverter and just got a sine wave one and theyre heaps more robust and betterer I reckon anyways. Would have had a 350w sine wave inverter if I knew how to work e-bay better.
.
Time is an illusion produced by the passage of history
.

Lifetime Member
My Profile  My Blog  My Position  Send Message
Moderator

0
FollowupID: 331325

Follow Up By: Member - Jeff M (WA) - Tuesday, Aug 03, 2004 at 18:01

Tuesday, Aug 03, 2004 at 18:01
You're probally right about outlasting the laptop! LOL.
Yeah, I still reckon buying the Jaycar 12v Unit is the best option for people running Ozi while traveling, it's just neater, safer, more efficiant. However I still agree that having an invertor of some description on board is handy, just make sure you can isolate it for water crossings, nothing like having 240v under the drivers seat (between your legs) while doing deep crossings hey! LOL
Oooo, I'm crossing my legs just thinking about it!
0
FollowupID: 331328

Reply By: Member - Sand Man (SA) - Tuesday, Aug 03, 2004 at 14:50

Tuesday, Aug 03, 2004 at 14:50
Hi Ya Jimbo,

I agree. I was also led to believe that "some" Laptops required a pure sign wave to operate, but this was from a manufacturer/distributor of the more expensive type of inverter.

I also have a "cheapie" 300 watt modified sign wave inverter which powers my IBM Thinkpad without any problems whatsoever. Cost me about $130 from JCAR whom also sell the more expensive pure sign wave unit.

The salesperson said "what do you want the expensive one for?"
He said (nice bloke) try the cheaper one and if it doesn't work, we'll refund your money.

Sometimes you do get a helpful dude behind the counter.
Bill


I'm diagonally parked in a parallel Universe!

Member
My Profile  My Blog  My Position  Send Message

AnswerID: 71071

Follow Up By: Utemad - Tuesday, Aug 03, 2004 at 14:57

Tuesday, Aug 03, 2004 at 14:57
I have the Jaycar 200w inverter. Runs my HP laptop fine but not my Dad's Dell. The Dell won't even charge the battery from the inverter just trips the inverter out. I have read from other threads that Dells need a pure sine wave or some sort of genuine adaptor or something.

Utemad
0
FollowupID: 331297

Follow Up By: Member - Wim (Bris) - Tuesday, Aug 03, 2004 at 15:08

Tuesday, Aug 03, 2004 at 15:08
Utemad
Tried my Dell on 150w no joy, same problem as you. Now have 300w unit and o/k. Not sine wave either. Old 150w will charge laptop but not run.

Regards
Camper setup
July 2012 - Hay River & Binns track
VKS 737 Mobile 0091
Selcall 0091

Lifetime Member
My Profile  My Blog  Send Message

0
FollowupID: 331301

Follow Up By: Bonz (Vic) - Tuesday, Aug 03, 2004 at 17:45

Tuesday, Aug 03, 2004 at 17:45
I was going to say if it trips out the inverter the problem is watt and how much, try something like 300w or larger. Dick Smith has a 300w pure sine wave for about $295, dual outlets for 240v on the front and a whole lot more size and heatsinks and robustness built in, also its 1000w surge, so it'll overcome the "starting" current of some devices. When you price inverters look for the surge rating as well, as some devices can pull up to three times their running current on starting.
.
Time is an illusion produced by the passage of history
.

Lifetime Member
My Profile  My Blog  My Position  Send Message
Moderator

0
FollowupID: 331320

Reply By: Member - Tim D (VIC) - Tuesday, Aug 03, 2004 at 15:22

Tuesday, Aug 03, 2004 at 15:22
I have the same problem gone through 3 invertors over the last 12 months trying to run my toshiba laptop but since I spent $79 and got the laptop 15-22volt one from jaycar no more problem
AnswerID: 71077

Follow Up By: Member - Jimbo (VIC) - Tuesday, Aug 03, 2004 at 16:31

Tuesday, Aug 03, 2004 at 16:31
Tim,

When you say you've gone through 3 invereters do you mean they died or just didn't work in the first place. Is mine likely to die on me if I use the fliptop off it?
0
FollowupID: 331308

Reply By: Willem - Tuesday, Aug 03, 2004 at 15:49

Tuesday, Aug 03, 2004 at 15:49
I was advised to buy a Pure Sinewave inverter for the laptop which I did. The 150watt inverter at a cost of $280 cooked a condensor when I married the laptop to it when running Oziexplorer. My mate fixed the inverter and since then I have bought a Kerio 12v dc laptop power source and it works very well. The inverter still sits there for running a variety of appliances when needed.
AnswerID: 71079

Follow Up By: Member - Ray - Tuesday, Aug 03, 2004 at 16:22

Tuesday, Aug 03, 2004 at 16:22
Inverters? Laptops? Digital mapping? Willem wash your mouth out.
0
FollowupID: 331306

Follow Up By: ExplorOz Team - Michelle - Wednesday, Aug 04, 2004 at 01:54

Wednesday, Aug 04, 2004 at 01:54
...and I have the proof here that he does use it. Our Willem has recorded actual OziExplorer plot files to accompany the new Flinders trek notes that he's survyed for us recently. You'll see them published soon too which means you can even download his plot files and drive them yourself.
Michelle Martin
Marketing & Customer Support
I.T. Beyond Pty Ltd / ExplorOz

Lifetime Member
My Profile  My Blog  My Position  Send Message
Moderator

0
FollowupID: 331399

Reply By: Big Kidz (Andrew & Jen) - Tuesday, Aug 03, 2004 at 17:50

Tuesday, Aug 03, 2004 at 17:50
Hi Jimbo

I had normal Dick Smith Inverter that was not pure sine wave but a square like me. It worked quite well for a while but my laptop power supply used to get hotter than when at home and it also made a louder buzzing sound when plugged in. After a while it seemed to make the power supply overload and we had to turn it off and wait till things cooled down. I got nervous after hearing about them burning out the notebook power supply and changed to a Jaycar Pure Sine wave inverter and it does not run cooler and quieter.

Andrew
AnswerID: 71107

Reply By: brett - Tuesday, Aug 03, 2004 at 21:30

Tuesday, Aug 03, 2004 at 21:30
Switch mode power supply's are most likely to be the least affected by a modified sine wave. The people that were told they need a pure sinewave did they tell you why? The first thing a switch mode supply does to the incoming 240V is fully rectify it and produce DC, then it switches this DC at a rate of approx 30KHz and converts it back to AC before going through a very small transformer to reduce the voltage to what ever is required, then rectified and regulated to produce a very stable regulated DC supply. By the time the incoming 240 AC is rectified then chopped up at 30Khz it really doesn't matter what the incoming AC looked like, whether it was a pure sinewave or a stepped one doesn't really matter. You will get far better results with a switch mode than a conventional iron cored transformer when run from a modified sinewave. The iron cored transformer will become very innefficient with a modified sine wave, it will get hotter and produce less current. The switch mode supply is the one that doesn't weigh much, feels like there's not much in side it.
AnswerID: 71148

Sponsored Links

Popular Products (13)