All you need is 2 25amp diodes and hook up so it looks like one half of
a4 diode full wave bridge rectifier, or it looks like a 2 diode full
wave bridge rectifier. The output is positive, and the input of each
diode is the positive output from each power supply.

in + |
\
+ out
/
in + |

pos from power1 to diode | output tied to second diode output
common output is positive at amp/power1 + amp/power2
pos from power2 to diode | output tied to first diode output

I would still supply each amp separately, due to voltage requirements.

Bob N9LVU

wrote:
I just had two powersupplies and ran the cables together so a simple
way of putting it would be that I have an amp, and i took the + from
both powersupplies, and put them to the + on the amp and the same with
the -. do you think it would work for me to get some bridge rectifiers
from radioshack? (25 amp bridge rectifier is $3.50 or something like
that,) get 2 of them and isolate each powersupply?

On 2 Jan 2005 18:53:36 -0800, wrote:

I just had two powersupplies and ran the cables together so a simple
way of putting it would be that I have an amp, and i took the + from
both powersupplies, and put them to the + on the amp and the same with
the -. do you think it would work for me to get some bridge rectifiers
from radioshack? (25 amp bridge rectifier is $3.50 or something like
that,) get 2 of them and isolate each powersupply?

Go to your local auto supply store and get a reverse-polarity
two-battery isolator. Tell them that you are running a
positive-ground British RV or something exotic like that. These
devices exist but they have to be ordered from the warehouse. They
consist of two horse-size diodes mounted on a heat sink with nice
big screw terminals. There should be a clear hook-up diagram with
it. This will be cheaper and easier than buying the components and
manufacturing the device yourself.

Connect one P/S to one input, and the other P/S to the other input.
Connect the load (amps) to the output/common. Warning - if one
supply has a slightly greater output voltage than the other, that
one will pick up the whole load. Digital metering of each supply's
output and the load voltage (nominally 0.7 V below the supply
voltage) is important.

That's how I run my communications center, with a big marine
gel-cell battery floating on the DC bus (13.8 V). Haven't had a
problem in five years' continuous duty.

--
73 de K2ASP - Phil Kane

On 2 Jan 2005 18:53:36 -0800, wrote:

I just had two powersupplies and ran the cables together so a simple
way of putting it would be that I have an amp, and i took the + from
both powersupplies, and put them to the + on the amp and the same with
the -. do you think it would work for me to get some bridge rectifiers
from radioshack? (25 amp bridge rectifier is $3.50 or something like
that,) get 2 of them and isolate each powersupply?

Go to your local auto supply store and get a reverse-polarity
two-battery isolator. Tell them that you are running a
positive-ground British RV or something exotic like that. These
devices exist but they have to be ordered from the warehouse. They
consist of two horse-size diodes mounted on a heat sink with nice
big screw terminals. There should be a clear hook-up diagram with
it. This will be cheaper and easier than buying the components and
manufacturing the device yourself.

Connect one P/S to one input, and the other P/S to the other input.
Connect the load (amps) to the output/common. Warning - if one
supply has a slightly greater output voltage than the other, that
one will pick up the whole load. Digital metering of each supply's
output and the load voltage (nominally 0.7 V below the supply
voltage) is important.

That's how I run my communications center, with a big marine
gel-cell battery floating on the DC bus (13.8 V). Haven't had a
problem in five years' continuous duty.

--
73 de K2ASP - Phil Kane

I just had two powersupplies and ran the cables together so a simple
way of putting it would be that I have an amp, and i took the + from
both powersupplies, and put them to the + on the amp and the same with
the -. do you think it would work for me to get some bridge rectifiers
from radioshack? (25 amp bridge rectifier is $3.50 or something like
that,) get 2 of them and isolate each powersupply?

Did you isolate the supplies with high power diodes?? Or run each amp on
it's own power supply.

Bob N9LVU

wrote:
Is it possible to run two radioshack switching supplies in parallel? I
have tried it however one always seems to shut down, so i would only be
getting 25 amps max. I need all the amperage I can get because I am
running two car audio amplifiers in my room... Thanks for any advice
or instructions!

-Matt

In article .com,
says...

Is it possible to run two radioshack switching supplies in parallel? I
have tried it however one always seems to shut down, so i would only be
getting 25 amps max. I need all the amperage I can get because I am
running two car audio amplifiers in my room... Thanks for any advice
or instructions!

Why in the Multiverse would you need that much audio power in your
room?

Do you have no concern for the quality of your hearing in later
life?

sigh Ahh, well... You need to diode-isolate the supplies, as has
been pointed out. I would add that it may be a good idea to use Schottky
power devices as opposed to generic diodes. Schottkys have a much lower
forward voltage drop.

Run the positive lead from each supply to the anode side of one
diode. Tie the cathode side of the diodes together, and take your common
positive output from there. The ground leads may be tied together
without isolation.

Good luck. Hope your neighbors don't object to the noise.


--
Dr. Anton T. Squeegee, Director, Dutch Surrealist Plumbing Institute.
(Known to some as Bruce Lane, ARS KC7GR,
kyrrin (a/t) bluefeathertech[d=o=t]calm -- www.bluefeathertech.com
"If Salvador Dali had owned a computer, would it have been equipped
with surreal ports?"

wrote in message
oups.com...
Is it possible to run two radioshack switching supplies in parallel? I
have tried it however one always seems to shut down, so i would only be
getting 25 amps max. I need all the amperage I can get because I am
running two car audio amplifiers in my room... Thanks for any advice
or instructions!


Yes, this would be possible but not the best choice.

Check out the Astron power supplies, in particular the RS-70M.
It should provide sufficient power, is very well regulated.
Google will find them for you.

--

... Hank

http://horedson.home.att.net
http://w0rli.home.att.net

Motorhome accesories include the use of 2 batteries with diodes. So check
with some local motorhome dealers.

--

73
Hank WD5JFR
wrote in message
oups.com...
Is it possible to run two radioshack switching supplies in parallel? I
have tried it however one always seems to shut down, so i would only be
getting 25 amps max. I need all the amperage I can get because I am
running two car audio amplifiers in my room... Thanks for any advice
or instructions!

-Matt

In article .com,
says...

Is it possible to run two radioshack switching supplies in parallel? I
have tried it however one always seems to shut down, so i would only be
getting 25 amps max. I need all the amperage I can get because I am
running two car audio amplifiers in my room... Thanks for any advice
or instructions!

Why in the Multiverse would you need that much audio power in your
room?

Do you have no concern for the quality of your hearing in later
life?

sigh Ahh, well... You need to diode-isolate the supplies, as has
been pointed out. I would add that it may be a good idea to use Schottky
power devices as opposed to generic diodes. Schottkys have a much lower
forward voltage drop.

Run the positive lead from each supply to the anode side of one
diode. Tie the cathode side of the diodes together, and take your common
positive output from there. The ground leads may be tied together
without isolation.

Good luck. Hope your neighbors don't object to the noise.


--
Dr. Anton T. Squeegee, Director, Dutch Surrealist Plumbing Institute.
(Known to some as Bruce Lane, ARS KC7GR,
kyrrin (a/t) bluefeathertech[d=o=t]calm -- www.bluefeathertech.com
"If Salvador Dali had owned a computer, would it have been equipped
with surreal ports?"

wrote in message
oups.com...
Is it possible to run two radioshack switching supplies in parallel? I
have tried it however one always seems to shut down, so i would only be
getting 25 amps max. I need all the amperage I can get because I am
running two car audio amplifiers in my room... Thanks for any advice
or instructions!


Yes, this would be possible but not the best choice.

Check out the Astron power supplies, in particular the RS-70M.
It should provide sufficient power, is very well regulated.
Google will find them for you.

--

... Hank

http://horedson.home.att.net
http://w0rli.home.att.net