Speakerplans.com Homepage
Forum Home Forum Home > General > 12v Powered Systems
  New Posts New Posts RSS Feed - TH & Unity Horn 24v Solar sound system
  FAQ FAQ  Forum Search   Events   Register Register  Login Login

TH & Unity Horn 24v Solar sound system

 Post Reply Post Reply Page  <1 9101112>
Author
Message
Phil B View Drop Down
Old Croc
Old Croc
Avatar

Joined: 21 November 2004
Location: Melbourne
Status: Offline
Points: 2260
Post Options Post Options   Thanks (0) Thanks(0)   Quote Phil B Quote  Post ReplyReply Direct Link To This Post Posted: 01 April 2020 at 12:43pm
Well we snuck in with our last gig on Sat 14th March... a day before lockdown. So here's a few snaps from the Last of the Summer 2020 vintage gigs...to remind us all what gigs were !!!

First off is one of my favourite events .. we provide sound for Melbourne Girls College Cinema Night. They have an awesome curriculum pushing alternative tech and how energy is produced / stored etc. They use pedal powered generators to charge a battery bank all day which then powers the projector at night for the film screening... we provide the off grid sound system. As well as the screening the students show off their talent with some small band / solo performances ....









The hound is of course the team boss... and goes to all my gigs.

Next up was a small " boutique " festival upstate out of Melb... Festival #23 a lovely setting, some really nice eclectic acts and generally some lovely people.. we had to turn half the system back outside after the Djs got their wish to play in the sun, in the end a great choice... we ran bands inside after dark. A highlight for me was having Freq Nasty give our " outside" half a good test with his afternoon set. The keystones were impressive..just two boxes off an FFa 6K got the place rumbling !













And the last gig for 2020... aptly named Come Together Festival .. always a tricky one for us. We need both solar trailers as we do lights , sound and backline. No change over times , just band after band. But as this was lock-down day minus one we had a few cancellations. Another lovely gig with some awesome bands











And that was the end of our gigs..... time to do the maintenance and yearly clean...and it's only Autumn...


Edited by Phil B - 01 April 2020 at 11:59pm
Mostly harmless.... except if catering is shut.

Solar Sound System Shennanigans..http://diyhifi.biz/
Back to Top
Phil B View Drop Down
Old Croc
Old Croc
Avatar

Joined: 21 November 2004
Location: Melbourne
Status: Offline
Points: 2260
Post Options Post Options   Thanks (0) Thanks(0)   Quote Phil B Quote  Post ReplyReply Direct Link To This Post Posted: 18 July 2020 at 2:32am


Some VERY big caps, originally used on electric locomotives in the USA ! These are to go over each 12v bank to see if we can reduce " ripple" in the batteries when the inverter is working really hard. Modern amps tend to demand huge current very quickly and the batteries just can't react quick enough.

I've told everyone to not touch the terminals as the short circuit ampage is frightening !

.p.
Mostly harmless.... except if catering is shut.

Solar Sound System Shennanigans..http://diyhifi.biz/
Back to Top
fatfreddiescat View Drop Down
Young Croc
Young Croc
Avatar

Joined: 15 October 2010
Location: N.E.Wales
Status: Offline
Points: 895
Post Options Post Options   Thanks (0) Thanks(0)   Quote fatfreddiescat Quote  Post ReplyReply Direct Link To This Post Posted: 18 July 2020 at 9:27am
Bloomin eck, nice find.
Back to Top
slaz View Drop Down
Old Croc
Old Croc
Avatar

Joined: 27 November 2009
Location: London E2
Status: Offline
Points: 2627
Post Options Post Options   Thanks (0) Thanks(0)   Quote slaz Quote  Post ReplyReply Direct Link To This Post Posted: 18 July 2020 at 9:55am
Fookinell. Well if they don't cure the ripple you could probably use em for a spot of welding :-)

REMEMBER....POLITICIANS AND DIAPERS SHOULD BE CHANGED OFTEN AND FOR THE SAME REASON
Back to Top
odc04r View Drop Down
Old Croc
Old Croc
Avatar

Joined: 12 July 2006
Location: Sarfampton
Status: Offline
Points: 5483
Post Options Post Options   Thanks (0) Thanks(0)   Quote odc04r Quote  Post ReplyReply Direct Link To This Post Posted: 18 July 2020 at 8:00pm
Well they are quite something, yes you definately want to be sure those are discharged before working with them.
Back to Top
bass*en*mass View Drop Down
Old Croc
Old Croc
Avatar

Joined: 03 September 2009
Location: "unknown"
Status: Offline
Points: 4008
Post Options Post Options   Thanks (0) Thanks(0)   Quote bass*en*mass Quote  Post ReplyReply Direct Link To This Post Posted: 18 July 2020 at 8:56pm
Lovely Jobs you got there Phil..! Bonus marks and congrats for the proof solar/battery powered systems do work.. :)

Back to Top
Xoc1 View Drop Down
Registered User
Registered User


Joined: 15 October 2012
Location: Devon UK
Status: Offline
Points: 251
Post Options Post Options   Thanks (0) Thanks(0)   Quote Xoc1 Quote  Post ReplyReply Direct Link To This Post Posted: 18 July 2020 at 11:41pm
How do you connect a capacitor that big though. Do you need to bring it up to voltage slowly before connecting it to the battery, almost like a soft start?
Back to Top
Phil B View Drop Down
Old Croc
Old Croc
Avatar

Joined: 21 November 2004
Location: Melbourne
Status: Offline
Points: 2260
Post Options Post Options   Thanks (0) Thanks(0)   Quote Phil B Quote  Post ReplyReply Direct Link To This Post Posted: 19 July 2020 at 5:28am
Originally posted by Xoc1 Xoc1 wrote:

How do you connect a capacitor that big though. Do you need to bring it up to voltage slowly before connecting it to the battery, almost like a soft start?


I'm looking into that !! I'll let you know how we go...

.p.
Mostly harmless.... except if catering is shut.

Solar Sound System Shennanigans..http://diyhifi.biz/
Back to Top
odc04r View Drop Down
Old Croc
Old Croc
Avatar

Joined: 12 July 2006
Location: Sarfampton
Status: Offline
Points: 5483
Post Options Post Options   Thanks (0) Thanks(0)   Quote odc04r Quote  Post ReplyReply Direct Link To This Post Posted: 19 July 2020 at 12:04pm
A current limited charging arrangement probably would not be a bad idea. Lot of stress on the batteries otherwise I would think during turn on. Would depend what you are running of course, of typical SLA type arrangement I'd have to guess would be fine. After all your typical SLA will fire a starter motor for many years and those draw a good few A for seconds.
Back to Top
studio45 View Drop Down
Old Croc
Old Croc
Avatar

Joined: 16 October 2007
Location: United Kingdom
Status: Offline
Points: 3843
Post Options Post Options   Thanks (0) Thanks(0)   Quote studio45 Quote  Post ReplyReply Direct Link To This Post Posted: 19 July 2020 at 2:46pm
You definitely need a soft start - a discharged supercap bank is a dead short and will pull hundreds of amps from a lead-acid bank if you just hook er right up. Simplest solution would be a relay and some 12v lamps, arranged such that the lamps are in series with the positive line to the caps when they're flat, and switched out of circuit when the voltage gets to say 12v (activates the relay coil). Some power loss in said coil, perhaps a MOSFET circuit could be more efficient. 
Of course if the cap bank drops below 12v at all during operation this might not work out too well, with the bulbs switching in and out too often. I guess you'd have to try it out.
Studio45 - Box Builder Commotion Soundsystem -Mobile PA
Back to Top
odc04r View Drop Down
Old Croc
Old Croc
Avatar

Joined: 12 July 2006
Location: Sarfampton
Status: Offline
Points: 5483
Post Options Post Options   Thanks (0) Thanks(0)   Quote odc04r Quote  Post ReplyReply Direct Link To This Post Posted: 19 July 2020 at 9:52pm
I'd not disagree, but playing devil's advocate a starter motor could easily draw 50A+ for a good few seconds sustained and SLAs are doing that every day. This cap bank may pull higher, but probably for a shorter time on turn on.

That said, first thing I would do is the maths, then I'd consult some datasheets, and then I'd probably be off to build some kind of current limiter :)

But there's no free lunch though. If you're going to head down the route of classic 3 terminal regulation with a reference source, pass device and feedback loop, you are going to lose some voltage over it. You'll get a current limiter, but may lose ~0.6V from the battery voltage over it at best. Maybe this is not a problem.


Back to Top
studio45 View Drop Down
Old Croc
Old Croc
Avatar

Joined: 16 October 2007
Location: United Kingdom
Status: Offline
Points: 3843
Post Options Post Options   Thanks (0) Thanks(0)   Quote studio45 Quote  Post ReplyReply Direct Link To This Post Posted: 20 July 2020 at 11:00am
Well, actually SLA (sealed lead acid/gel cell/AGM/maintenance-free) aren't any good at all for starter motor duty, which is actually 300A+ for a medium sized engine. Only flooded lead acid (the kind with liquid acid inside, that you can't tip over else it dribbles out) can cope with that kind of instantaneous current.

I suppose you could be brave, and just accept the massive spark that happens the first time you hook up the caps to the batteries; if you're then leaving them connected all the time, not a problem; it will be a doozy though!

or, use the bulb to limit current initially via some croc clip leads, then when charged bolt up the connection permanently.
Studio45 - Box Builder Commotion Soundsystem -Mobile PA
Back to Top
 Post Reply Post Reply Page  <1 9101112>
  Share Topic   

Forum Jump Forum Permissions View Drop Down

Forum Software by Web Wiz Forums® version 12.03
Copyright ©2001-2019 Web Wiz Ltd.

This page was generated in 0.078 seconds.