I recently made a speakerbox for my bike using a dewalt sander toolbox. I put 2 5"x7" speakers, a 12v 12ah SLA battery, and a Lepai TA2020 amp with an on/off switch wired in between the battery & amp. The setup worked great for 2 weeks, used 3 times for 3-4 hours each time. Afterwards the battery has been hooked to a battery tender junior to charge & maintain. Yesterday I went to use it and heard distortion & realized the positive connector to the battery was loose, I secured the wire & then went to use it a few hours later & the amplifier would not turn on. I tested the amp at home plugged directly into the wall, and it is still totally dead. The battery has 13+volts, which I assume is fine. I'm wondering did I ruin the amp? Should my setup be hooked up differently?
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
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1) very cool looking sound system 
2) you show everything but the main suspect, the amplifier .
Some doubts still not cleared, I had read the post earlier but didn't answer because it was not clearly written, suspect others did the same:
3)
we don't know what you used and what's meant as a trickle charger for a car battery may dry up or kill a way smaller SLA.
I'm worried by your 13V reading, when unplugged from the charger battery shows somewhat more for a few minutes, but in, say, 1/2 hour it settles to 12.6V
If just unplugged (or even worse, still trickle charging) , voltage can be anything up to 15V , but that's meaningless.
So wait at least 1/2 hour and remeasure, that's the "good" one.
you have an extra 12V supply for the Lepai?
show it.
measure that it supplies 12V (or thearabouts) both with and without load.
It might show 12V to a multimeter and suddenly collapse under load.
2) you show everything but the main suspect, the amplifier .
Some doubts still not cleared, I had read the post earlier but didn't answer because it was not clearly written, suspect others did the same:
3)
show it
show it
we don't know what you used and what's meant as a trickle charger for a car battery may dry up or kill a way smaller SLA.
I'm worried by your 13V reading, when unplugged from the charger battery shows somewhat more for a few minutes, but in, say, 1/2 hour it settles to 12.6V
If just unplugged (or even worse, still trickle charging) , voltage can be anything up to 15V , but that's meaningless.
So wait at least 1/2 hour and remeasure, that's the "good" one.
maybe the repair was not good enough, measure that proper voltage actually reaches the amplifier and that it didn't blow a fuse.
what does that mean?
you have an extra 12V supply for the Lepai?
show it.
measure that it supplies 12V (or thearabouts) both with and without load.
It might show 12V to a multimeter and suddenly collapse under load.
Thanks very much for the reply.
Unfortunately I've already mailed the amplifier back to Amazon so I cannot share any photos of it with this setup. With that said hopefully these additional photos will help.
Here are photos of the Batter Tender Junior, shown how I hook it up when charging. The battery has not been hooked up to the charger and plugged into the wall at all today. I've shown my multimeter in the photo to make sure I am reading/using it correctly in this case it appears to be at 14v or 15v. Also shown is a photo of the same test performed on the DC jack while hooked up to the battery and my switch turned on, still showing 14v or 15v. Before sending the Lepai Amp back I did open it up and did not find any fuse to speak of. The only fuse in the entire setup that I am aware of is on the cable for the battery charger and it looks fine.
Thanks again, let me know any other info I can provide.
Unfortunately I've already mailed the amplifier back to Amazon so I cannot share any photos of it with this setup. With that said hopefully these additional photos will help.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
Here are photos of the Batter Tender Junior, shown how I hook it up when charging. The battery has not been hooked up to the charger and plugged into the wall at all today. I've shown my multimeter in the photo to make sure I am reading/using it correctly in this case it appears to be at 14v or 15v. Also shown is a photo of the same test performed on the DC jack while hooked up to the battery and my switch turned on, still showing 14v or 15v. Before sending the Lepai Amp back I did open it up and did not find any fuse to speak of. The only fuse in the entire setup that I am aware of is on the cable for the battery charger and it looks fine.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
Thanks again, let me know any other info I can provide.
Thanks for the reply. I only use the charger at the end of a night of using the speaker. With the switch off I would unplug the dc jack from the amp, then unplug the (+) and (-) connections at the battery. At that point I would attach the (+) and (-) alligator clips from the charger to the battery and plug the charger into the wall. When charged fully and ready to use the system again I would repeat this process in reverse. I figured it would be good to isolate the battery while charging so I have not left it hooked up to anything while charging.
My unsure areas within this setup were the following.
Other than the on/off switch should there be anything hooked up between the battery and amplifier?
Also the dc jack and wire I am using was scavenged from a random dc power adaptor, I just cut the plug end off and incorporated it into this setup.
Thanks again for any and all help. I've tried searching for info on the bike stereo setups all over and either find setups with no info on how all the connections and components should be done. Or in the case of this site I believe I found the info but it is for the most part over my head.
My unsure areas within this setup were the following.
Other than the on/off switch should there be anything hooked up between the battery and amplifier?
Also the dc jack and wire I am using was scavenged from a random dc power adaptor, I just cut the plug end off and incorporated it into this setup.
Thanks again for any and all help. I've tried searching for info on the bike stereo setups all over and either find setups with no info on how all the connections and components should be done. Or in the case of this site I believe I found the info but it is for the most part over my head.
Important notice:
You should *never*, and I mean absolutely *never*, use a SLA battery in a circuit without a suitable fuse. These batteries are capable of delivering very high currents into a short circuit! This can lead to fires or even exploding batteries!
If anything goes wrong inside your box, the SLA battery is capable of keeping those tiny wires glowing red or white hot for minutes, melting everything nearby or setting the whole thing on fire!
First step before reinstalling the amp: Mount an appropriately sized fuse holder into your device!
Regards,
Rundmaus
You should *never*, and I mean absolutely *never*, use a SLA battery in a circuit without a suitable fuse. These batteries are capable of delivering very high currents into a short circuit! This can lead to fires or even exploding batteries!
If anything goes wrong inside your box, the SLA battery is capable of keeping those tiny wires glowing red or white hot for minutes, melting everything nearby or setting the whole thing on fire!
First step before reinstalling the amp: Mount an appropriately sized fuse holder into your device!
Regards,
Rundmaus
Thanks very much for your reply! This sounds like it may be the cause of the issues. Here is a link to the info about the amp that we are using:
http://www.amazon.com/gp/product/B0049P6OTI?psc=1&redirect=true&ref_=oh_aui_detailpage_o03_s00
It would typically use a 12v 2A power supply, and I am using a 12V 12ah SLA battery, do you have a suggestion of what size fuse I should use? Bus type or tube type? does it matter? Lastly, where in the setup should it be wired? Between the (+) of the battery and the on/off switch?
http://www.amazon.com/gp/product/B0049P6OTI?psc=1&redirect=true&ref_=oh_aui_detailpage_o03_s00
It would typically use a 12v 2A power supply, and I am using a 12V 12ah SLA battery, do you have a suggestion of what size fuse I should use? Bus type or tube type? does it matter? Lastly, where in the setup should it be wired? Between the (+) of the battery and the on/off switch?
indeed good points by RM >always use an inline fuse located close to the battery terminals. doesn't matter which side, but plus side is traditional for neg. grounded cases
2x20W/12V = 3.3 > use a 3A or 4A SB fuse, make sure it's inclosed in an insulated covered type holder, infact all your fast-on connectors can be sleeved as well. You can probably use some heat shrink in a pinch
2x20W/12V = 3.3 > use a 3A or 4A SB fuse, make sure it's inclosed in an insulated covered type holder, infact all your fast-on connectors can be sleeved as well. You can probably use some heat shrink in a pinch
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Take a 12V light bulb, like a #194 automotive marker light, and temporarily connect it across the 12V amplifier power connector. If you can switch the light on and off you have a good line and battery. If not, turn it on and start measuring with your voltmeter to find the high resistance connection or switch.
Rundmaus -- excellent point about the fuse. Any fuse holder will work, even the ones you get from the auto parts store. Just make sure you use a fuse that is at least 1.333 X your max operating current. If you don't the fuse may have an early failure due to metal fatigue from internal heating. I would put it in the + line.
Tina
Rundmaus -- excellent point about the fuse. Any fuse holder will work, even the ones you get from the auto parts store. Just make sure you use a fuse that is at least 1.333 X your max operating current. If you don't the fuse may have an early failure due to metal fatigue from internal heating. I would put it in the + line.
Tina
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