It is likely that the charger would be in a current-limited mode when you first connected it, as the batteries would be trying to take more current than the charger could supply. Normally the charger would change from a current-limited mode to a constant-voltage mode as the batteries charged up. 30V is too high to leave connected to the batteries once they have charged up. More advanced chargers alter the float-charge voltage depending on the battery temperature, but for a normal charger, anything over 28V (for a 24V SLA battery) is too high to leave connected as a float charger.
When I'm charging a 24V battery pack from a bench PSU, I set the PSU to 27.6V and monitor the battery current. Once the current taken from the PSU by the battery pack has dropped below 50mA (for 7A-H or 12 A-H batteries) then it is effectively fully charged and can be disconnected.
When I'm charging a 24V battery pack from a bench PSU, I set the PSU to 27.6V and monitor the battery current. Once the current taken from the PSU by the battery pack has dropped below 50mA (for 7A-H or 12 A-H batteries) then it is effectively fully charged and can be disconnected.
Well, 30v is still higher than I would use! I have a Chinese-made 24V charger myself, intended for charging the 24V battery pack in an electric scooter, so it really is meant to charge batteries of 17 amp-hours or so. If the 30V supply is connected for too long it will cause excess pressure and temperature in the smaller 7 amp-hour batteries. Perhaps you could leave the charger connected until the green light comes on and see what the charger voltage does.
Does the charger buzz all the time, or only when it is current limiting? Is the charger a switch-mode type (looks like a laptop PSU), or is it a traditional mains-transformer type? Either way, a 50Hz or possibly 100Hz buzz isn't surprising. Is there a current rating on the charger? I guess it will only need to be connected for 3 or 4 hours to fully charge the batteries, so the buzz might not be too much of a problem.
Does the charger buzz all the time, or only when it is current limiting? Is the charger a switch-mode type (looks like a laptop PSU), or is it a traditional mains-transformer type? Either way, a 50Hz or possibly 100Hz buzz isn't surprising. Is there a current rating on the charger? I guess it will only need to be connected for 3 or 4 hours to fully charge the batteries, so the buzz might not be too much of a problem.
EDIT: FWIW: I've been using the TK2050 sure board with 8800mAh 22.2v Li-ion cells outside and in other places without a mains supply and it sounds very nice.
The 4.7uH XXL's have been out of stock for months at Farnell, would you say there us much difference with the 6.8uH XXL's as they have plenty of 6.8uH XXL's in stock?
Last edited:
Check again now
Check the WE-PD XXL coils at 4.7uH again. Someone else just got some. If not, the 6.8 will sound much better than the stock coils.
I see I wrote 24V instead of 12V, it should of course be: connect + to + and - to - to charge with 12V charger !
Mine is a 4A charger made by "Coming Data" and bought on Ebay. It gives a regulated output of 27.8V, with a current limit at about 3.6A. it is almost totally silent.
Thanks, I've just check and they've now got over 200 in stock, I've ordered 8.
Hifimediy asked me yesterday if I could help him to sell the boards outside China because he don't have a paypal account or uses ebay. I accepted, as I want to get this out to more people so that we can explore how to tweak it. And I also thought it could be fun to be involved in this
I have been checking out shipping options out of china. This is (as everything else in China) not as simple and straightforward as in other places. I will try one shipper first and see how that works. The price will maybe have to be adjusted depending on how the shipping works.
We've settled on a price including shipping of 42USD. I will have two boards now, and more around 15th next month. PM me if you are interested. I think payment by paypal would be the easiest now. Maybe I could put them on ebay later, but I have never used ebay for selling, so I would have to look deeper into that.
I hope I can still be part of the discussion about this board even if I'm involved selling them. I'm only doing this because I was so impressed by this board and want to get it out to others.
I have been checking out shipping options out of china. This is (as everything else in China) not as simple and straightforward as in other places. I will try one shipper first and see how that works. The price will maybe have to be adjusted depending on how the shipping works.
We've settled on a price including shipping of 42USD. I will have two boards now, and more around 15th next month. PM me if you are interested. I think payment by paypal would be the easiest now. Maybe I could put them on ebay later, but I have never used ebay for selling, so I would have to look deeper into that.
I hope I can still be part of the discussion about this board even if I'm involved selling them. I'm only doing this because I was so impressed by this board and want to get it out to others.
Did you look at the dayton unit?
I have been playing with the thought of putting these boards in a cabinet together with a meanwell psu. I have a few friends that are in need of a new amp, but wouldnt accept having the board just sitting there without a case. Also I would want a case myself eventually, so I was thinking of finding a suitable case and make a few amps. I might consider making some extra and offer for sale. But this will not happen overnight..
Is the Dayton unit any good? I only know one place to get it and they're out of stock.
Is the Sig 30.2 comparable to Dayton? I guess the Sig 30.2 is so expensive due to the "fancy" cabinet/case and the touch sensitive power on/off button and of course the battery PSU. But if it the performance of the Dayton is nearly the same as the Sig 30.2 then I'll try it without any hassle.
- Status
- This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.