My DIY "Megabond" portable power station

OK so I have to post up my pictures of the same idea that I have been using for about a month.

MinGrey02Stg2 wrote in post #10273681
I understand they may have a decent discharge rate, but what about their surge rate? The battery pack for your heli uses probably around 16 to 20g wire and is plenty for the current that the servos/motor pull. I'd bet it doesn't have the surge power to start a small motorcycle engine, though. It would take a hell of a lipo pack to deliver 875 amps for 30 seconds like the lead acid battery in my setup is capable of. I would much rather run lipo packs if they were ideal because their weight would be such a help, but it would hurt the bank to see strobes fry them because their short surges.

I stand corrected... I did a little research and found this.

I'd say lipos would be perfect for something like this. With 125ah worth of them even at a modest 20C (for the cheaper ones) you are talking about 2500 amps continuously. Double that for a 30 sec burst. Newer lipo cells are rated at 40-60C.

it would be more complicated though, you would need the circuitry to keep the pack balanced and protect from over-discharging. That stuff is available for a DIYer or you can buy packs premade with all that built in.

Interesting project. My only comments would be to further what the others have said on the importance of:
1. insulating the positive terminal on both the battery and at the inverter
2. I would not use that w/o a GFCI

Also, I'm not saying it is not "pure sine wave"....but are you really sure it is ? A lot of this stuff these days coming out of china is being labeled "pure sine wave" when in reality it's modified sine wave. Let's just say maybe they are losing something in the translation !
I mean....I don't where this one was made or where you sourced it from, but I can tell you there is a difference sometimes in how this stuff gets marketed when it's manufactured here in the USA vs some of what comes out of china.

george m w wrote in post #10301330
Interesting project. My only comments would be to further what the others have said on the importance of:
1. insulating the positive terminal on both the battery and at the inverter
2. I would not use that w/o a GFCI

Also, I'm not saying it is not "pure sine wave"....but are you really sure it is ? A lot of this stuff these days coming out of china is being labeled "pure sine wave" when in reality it's modified sine wave. Let's just say maybe they are losing something in the translation !
I mean....I don't where this one was made or where you sourced it from, but I can tell you there is a difference sometimes in how this stuff gets marketed when it's manufactured here in the USA vs some of what comes out of china.

I've looked at the OSP video on youtube. The guy use a tecktronic scope and showed glitches on the sinewave. I dont think its a concern but its certainly not a "pure" sine wave.

A square wave is definitely a world apart from an analog sine. Hard to believe a china inverter would have lost translation in a "pure sine wave" inverter.

The sunforce 1000w unit looks promising but not sure of the signal output. Lotsa cheapy ones out there like powerjack and OSP. I just hope if there is failures that it simply dies and not destroys a strobe.

I am looking at Aims, Samlex and statpower/xantrex inverters for my diy.

Alan,
Yes....I agree that Samlex would be a good way to go. I am not saying the original poster has made a "bad" choice....I'm just saying that there is usually a reason that some of this stuff is "lower priced".
And for sure...I'd hate to fry several hundred dollars worth of monolights just because I was trying to save some money on a DIY project. I'm not an EE.....but I know enough to, "know what I don't know".

TroyRaymond wrote in post #10275605
I stand corrected... I did a little research and found this.

Your quote talks about a 5 Ah RC pack with two cells. You would have to connect 25 of those in parallel to have 125Ah. My two cell RC LiPo (60C) is around 250g in weight including hard case. I would say the 100 cells would weight around 5 kilos...

LiPo's are perfectly fine for this job save the price. The Chevrolet Volt is powered by a LiPo pack

Quick question relating to inverter. I am working on my own set-up with a car battery and 400 w PSW inverter. I hooked up my 640, 320 and 160 w/s lights and started getting a loud whistle sound. I unplugged all the lights and still get the loud whistle. Any idea what that may be?

robbscott wrote in post #10622858
Quick question relating to inverter. I am working on my own set-up with a car battery and 400 w PSW inverter. I hooked up my 640, 320 and 160 w/s lights and started getting a loud whistle sound. I unplugged all the lights and still get the loud whistle. Any idea what that may be?

I believe this was posted to another thread and gotten some responses. It's very hard to determine the cause or the exact nature of the problem but it would seem that you're overloading the inverter and trying to draw far more power than the inverter can deliver.

robbscott wrote in post #10622858
Quick question relating to inverter. I am working on my own set-up with a car battery and 400 w PSW inverter. I hooked up my 640, 320 and 160 w/s lights and started getting a loud whistle sound. I unplugged all the lights and still get the loud whistle. Any idea what that may be?

Does it only make the noise when all three lights are hooked up? If so, you're probably overloading the inverter. What battery are you using?

Seems like Paul Buff just figured out the LiPo:
http://www.alienbees.c​om/vmini.html

500 shots on one charge is good enough for me