DIY pure sine wave inverter

[Edwin Francis]

I believe Tim is correct -- the last para of the TS' original post says it. Put together a (commercially-made) inverter & sealed-acid battery (will need a charger as well), not design and build it from the ground up.

Here's one guy who did just this (all-in-one casing, circuit breakers and all) :
http://www.instructables.com/id/A-Portable-Power-Box-for-Photographers/

I suppose Sim Lim Tower (there was an earlier reference for inverters from there) is still the best place to look for the component parts you'll need. Don't really know how much you'll save though, and it probably won't be worth the time you spend on putting things together. Also, it would probably be a good idea to ask a friend who knows about these things to look over your plans and make recommendations (pref an electrical engineer)

 

[yamcake]

yes.. i dont intend to DIY the inverter itself.. haha. that will be quite crazy.
anyway, i want to put it together because i would want it to be more flexible, i.e fit a larger capacity battery, to it.. i estimate i'll save like 20% of the cost put together...

i'll go down sim lim tower to take a look this weekend.. haha...

 

[Yappy]

Sorry. I don't understand why pure sine wave got to do with teh power supply!

 

[tim]

Most low-cost inverters have modified square wave output (sometimes called modified sine
wave) with harmonic distortion of around 40%. They are an economical choice in power
systems where waveform is not critical. Their high surge capacity allows them to start
large motors while their high efficiency makes them economical when running small loads
like a stereo or a small light.

They can power most lighting, televisions, appliances and computers very well. We do not
recommend them for computer systems with laser printers.

Unfortunately, this type of inverter may destroy some low cost rechargeable tools and
flashlights, and their waveform will not allow many laser printers, copiers, light dimmers and
some variable speed tools to operate.

Some audio equipment will have a background buzz that may be annoying to music
connoisseurs. Due to the wave form and high harmonic distortion some motors will
consume more power on a modified square wave.

The result is more noise, heat and losses. This is not usually a problem if this type of wave
form is only being used for brief and infrequent backup power.

However, for continuous year-around use, a motor running hotter will have a
shortened expected life. You may even hear a distinct hum when running on modified
sine wave power.

The image below shows a typical modified sine wave as compared with a true sine wave.

 

[ZerocoolAstra]

yes.. i dont intend to DIY the inverter itself.. haha. that will be quite crazy.
anyway, i want to put it together because i would want it to be more flexible, i.e fit a larger capacity battery, to it.. i estimate i'll save like 20% of the cost put together...

i'll go down sim lim tower to take a look this weekend.. haha...

have to go down on saturday morning i think. They aren't open throughout the weekend, like Sim Lim Square.

 

[Yappy]

Most low-cost inverters have modified square wave output (sometimes called modified sine
wave) with harmonic distortion of around 40%. They are an economical choice in power
systems where waveform is not critical. Their high surge capacity allows them to start
large motors while their high efficiency makes them economical when running small loads
like a stereo or a small light.

They can power most lighting, televisions, appliances and computers very well. We do not
recommend them for computer systems with laser printers.

Unfortunately, this type of inverter may destroy some low cost rechargeable tools and
flashlights, and their waveform will not allow many laser printers, copiers, light dimmers and
some variable speed tools to operate.

Some audio equipment will have a background buzz that may be annoying to music
connoisseurs. Due to the wave form and high harmonic distortion some motors will
consume more power on a modified square wave.

The result is more noise, heat and losses. This is not usually a problem if this type of wave
form is only being used for brief and infrequent backup power.

However, for continuous year-around use, a motor running hotter will have a
shortened expected life. You may even hear a distinct hum when running on modified
sine wave power.

The image below shows a typical modified sine wave as compared with a true sine wave.

Thank you for taking the trouble to reply. Appreciate it very much!

 

[catchlights]

Thanks to Tim for the details info on inverter, and also thanks to TS and many others has contribute ideas and links.

Initially thinking of getting a Vagabond, however, now it seem not possible to get it
Rob Galbraith: Paul C. Buff ceases sale of products outside the U.S., Canada

I google the DIY portable power supply from the net, not just for using studio strobe on location, but also a portable power supply can be use for family outing.

The DIY idea it seem workable, however, most info found online are made for 110V, would appreciate any members expertise in this area could recommend parts and component for 220V and can be source locally.

Here are the links I found on research,

DIY Vagabond / power pack parts list

YouTube - Homemade Vegabond Inverter Portable Power Source

Flash / Strobe Topics DIY strobe lighting battery pack ...

DIY Portable Power

DIY Vagabond - Portable Power pack for Monolights at Erik Seo ...

DIY Vegabond II true Sin-Wave inverter to power your strobes

Tim Kemple » DIY: Alien Bees Power Pack — Lose Weight on Location

 

[kkcharles82]

I am an electronics design engineer by profession ( in power electronics ) for about 15 years. DO NOT attempt to DIY a pure sine wave inverter yourself. Give up the idea.... it is too complex for someone not in this line without proper test equipment and tools. It will take you years to built one....

go buy it from ebay or shops in SimLim Tower.

good luck,
Billy

I agree on that standpoint. If you are asking for schematics on pure sine inverters, you should really be buying one and not building one. It is very very complex and not a bunch of components that will fit and work at first go. I am a research student in inverter topology and design in NTU, I can tell you even myself and my fellow researchers here can face situations that we do not understand fully still (not the theory but the practical issues)