john stones 1 - Moderator Posted August 31, 2015 Share Posted August 31, 2015 This suitable for making a power supply unit for charging lipo's, biggest I use is 4s 3300mah, but am fed up charging one at a time so will be buying a charger to do four at once. John Quote Link to comment Share on other sites More sharing options...
Hugo Strugstad Posted August 31, 2015 Share Posted August 31, 2015 It is possible to use this, but it cold have has more Ampere. Chargin 4s 3300mAh batteries at 1c will require 49watts. Charging 4 of those, almost 200W. Your PSU can deliver max 14 Amps (168W at 12 v). If this is constant max current you may be Abel to charge 3 of your batteries at 1c simultaneosly. Quote Link to comment Share on other sites More sharing options...
John Privett Posted August 31, 2015 Share Posted August 31, 2015 I think that PSU will struggle to charge 4 x 4S, 3300 batteries at the same time. It's slightly worse than Hugo suggests, as at the end of the constant current phase of the charge, the charger has to supply 3.3A at 16.8v which is a little over 55W. Of course no charger is anything like 100% efficient, so the input poser to the charger will need to be more. How much more? I don't know! I'd be surprised if it was as little as 60W input per battery - which means 5A, or if all 4 reach that stage at the same time 20A. The PC PSU pictured is only rated at 14A at 12v. I use an old Microsoft Xbox PSU (a tenner off ebay), but it too would struggle with your requirement. It is rated at 16.5A at12v - a touch under 200W. It copes fine with the biggest batteries I charge - 2 x 3S 2700 mAh plus 2x 3S 3000mAh together. Quote Link to comment Share on other sites More sharing options...
john stones 1 - Moderator Posted August 31, 2015 Author Share Posted August 31, 2015 Cheers, I think I follow you...this one should be o.k then, scroll down it has all bumf. John Quote Link to comment Share on other sites More sharing options...
John Privett Posted August 31, 2015 Share Posted August 31, 2015 That one's good for 36A on the 12v rail, according to the spec, so much more like what you'll want. I assume you've already checked the numerous articles online specifying what you need to do to make a PC PSU function as a charger supply? Essentially (apart from modifying the connectors) you'll need to bridge two of the terminals (could do it with a switch if you wanted) that signals the PSU to actually turn on the outputs. Secondly - and this might not be needed on recent PSUs - you may need to put a load on the 5v line. Without this the 12v supply may not run at the correct voltage - as I said though, this might not be a problem these days. On the one I previously used, I put a 12v car bulb across the 5v line. It glows orange and as well as providing a load, reminds me that it's switched on - as if the fan whirring away isn't already enough of a clue! Quote Link to comment Share on other sites More sharing options...
john stones 1 - Moderator Posted August 31, 2015 Author Share Posted August 31, 2015 Thanks John, this one has an on/off switch at the back, yes I've been viewing the tutorials on converting one and i'll be asking questions when i'm unsure. John Quote Link to comment Share on other sites More sharing options...
John Privett Posted August 31, 2015 Share Posted August 31, 2015 The on/off switch at the back just "powers up" the power supply. Even when switched on at the back, it doesn't actually do anything useful until the two connections mentioned earlier are bridged. This is mimicking how it functions on a PC. Many PCs have that little switch on the back of the PSU, and I'd say that 99.99% of them are never turned off at that switch. So the PSU is 'live' at all times the PC is plugged in to the mains. But only when you press the "power" button" (which bridges those two connections mentioned earlier) does the PSU, and consequently the PC, burst into life. Quote Link to comment Share on other sites More sharing options...
john stones 1 - Moderator Posted August 31, 2015 Author Share Posted August 31, 2015 Cheers John, i'll ask questions when it turns up. John Quote Link to comment Share on other sites More sharing options...
Gavin Mack Posted September 1, 2015 Share Posted September 1, 2015 see link below on how to use ex server power supplies which are higher power than pc power supplies and easier to convert **LINK** Quote Link to comment Share on other sites More sharing options...
Brian Pearson Posted September 1, 2015 Share Posted September 1, 2015 I used two dps 600b power supplies I got 9ff ebay for twenty quid. Then wired them in series to give 24v. I can charge whatever I want....obviously limited to your charger. The details on how to do it are on the Web. You MUST isolate one unit. But it's fairly straightforward. Quote Link to comment Share on other sites More sharing options...
Masher Posted September 1, 2015 Share Posted September 1, 2015 Posted by Gavin Mack on 01/09/2015 10:02:29: see link below on how to use ex server power supplies which are higher power than pc power supplies and easier to convert **LINK** That's what I have done - good quality and cheap Quote Link to comment Share on other sites More sharing options...
Andy Meade Posted September 1, 2015 Share Posted September 1, 2015 Thanks for the link - I have 4 of those supplies in the loft I can use. I remember they were very noisy though! Quote Link to comment Share on other sites More sharing options...
FlyinBrian Posted September 1, 2015 Share Posted September 1, 2015 Posted by Masher on 01/09/2015 10:54:58: Posted by Gavin Mack on 01/09/2015 10:02:29: see link below on how to use ex server power supplies which are higher power than pc power supplies and easier to convert **LINK** That's what I have done - good quality and cheap Me too, very easy mod and works very well. Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.