Battery or Accu Power supply

[ralf]

what do you think about it?

i wonder about that schematic. when it`s switched on, there should be the ripple of the mains over the battery supply.
i think when the batteries supply the amp, the mains should not be connected to the battery.??!!!

Regards,
Ralf

[ralf]

Halojoy, (thanks for your statement)

how can one test the battery state.
how can i know if the batteries are full,
can the batteries be overloaded or underloaded and cause of that get damaged. how can i prevent that?
are there schematics or circuits to manage the fullfilling batteries?

regards,
Ralf

[ralf]

Originally posted by rtirion
Is it wise to want to feed an amplifier that draws at least 4
amperes all the time with batteries?
You will have a lot of work when you need to recharge them
every few hours of playtime.
Even if you decided to come up with a circuit that will handle the
charge job, (which is not a trivial task), you will have to ask
yourself if it is worth all the extra trouble/expenses.
Especcially if you know that there is a real good alternative in the form of an isolation transformer.
If you are going to use batteries I would shure like to read your experiences with them.

Regards.

show us other/better psu schematics....

regards,
Ralf

[Klaus]

Hi Ralf,

a friend of mine did many testss with power amps fead by accus. His statemant could be quoted in this way: it is extremely clear, but the dynamics is sufferíng a bit. I think the high inner dynamic resistance of the accus is the matter. They can not follow impulses fast enough, that is the reason that they need best big capacitors parallel.

Test it, make your experimences and please let us know...

Regards

Klaus

[Elso Kwak]

Hi all,
Please be carefull with car or even truck lead-acid batteries. A <B>HIGHLY </B>explosive mixture of hydrogen/oxygen gas can escape. This can blow up your listening room or entire home. Also the sulphuric-acid spattered around can seriously damage your eyes.
Please be carefull and place the car batteries <B>OUTSIDE</B> in the open air, well ventilated! Do not overcharge as this increases the risk of gaseruption.
Texas Instruments makes a nice charger controller IC but I think it is not intended for these monsters. If I would ever go this far I would use a <B>good quality</B> lead acid charger with overload protection and auto switch-off as sold in car accessoires shops. Also I would not choose the fast charge option as this increases the chance of gas eruption.
Don't make your hobby turn into a disaster!
See also:
http://db.audioasylum.com/cgi/m.pl?f...ve&r=&session=

[ralf]

Originally posted by Klaus
Hi Ralf,

a friend of mine did many testss with power amps fead by accus. His statemant could be quoted in this way: it is extremely clear, but the dynamics is sufferíng a bit. I think the high inner dynamic resistance of the accus is the matter. They can not follow impulses fast enough, that is the reason that they need best big capacitors parallel.

Test it, make your experimences and please let us know...

Regards

Klaus

Hi Klaus,

is it possible to communicate with yor friend about this, you know i live about 100km away from Frankfurt (near Hockenheim).

But, when one uses good and big capacitors, all problems should be overgone and the psu should follow big impulses fast.!?

Has anyone alternative PSU`s

Regards,

Ralf

[Klaus]

Hi Ralf,

the word “a friend” was to strong, it was just a mate, a buddy. I have lost contact to him since he moved his living location from Hamburg to ? one year ago. So sorry, no more contact available. He told me in former mails and a phone call about the results I quoted. As far as I remember he used strong industry batteries for emergency exit illumination systems at a ZAP solute amp.

If “good and big” caps could cover disadvantages of slow impulse capability of accus I´m not shure about. It could just be tested, I guess...

My personal opinion: with good PSU´s - using well oversized transformers, big and fast cans with faster impulse caps bridged, low-impedance soft recovery rectifiers, strong leads etc., and most important a appropriate cable from the fuse box to the hifi set in the appartment – the quality of the PSU is almost perfect. No battery needed for power amps. For pre-amps, phono-stages etc the story told totally different of cause!

Best regards to 100km south

Klaus

[Sparhawk]

Originally posted by ralf
how can one test the battery state.
how can i know if the batteries are full,
can the batteries be overloaded or underloaded and cause of that get damaged. how can i prevent that?
are there schematics or circuits to manage the fullfilling batteries?

regards,
Ralf

Determining the state of charge (SOC) of a battery is not an easy thing to do. For large lead-acid batteries (ie, car batteries) the most direct method is to measure the specific gravity of the electrolyte using a hydrometer. You can also estimate SOC from the battery voltage, but for this you need the voltage vs. SOC graph for your particular battery. Probably the most common way to measure SOC is with a watt-hour meter. You start with a fully charged battery, and keep track of watt-hours out vs. watt-hours in.

You should never discharge a lead-acid battery to lower than 50% depth of discharge (DOD). Doing so will warp the lead plates and rapidly kill the battery. Even 50% DOD is really too much for long battery life. A good deep-cycle lead acid battery (not a car battery) will last for 10 years or more with daily cycles to 20%DOD.

Typical car battery chargers are very bad for the battery. A good multi-stage charger with variable setpoints is essential for long battery life.

[ralf]

Hi, has no one an example for a really good conventional PSU? - which is worth to rival with Batteries?

Regards,
Ralf