APC backing up a scanner test I did...

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kc8qln

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I have a small 3 year old APC backup I was just using on a cheap TV. The model number is ES-725. The spec for the ES-725 shows 1 Hour 20 Minutes with 50 Watts. But, I am sure the scanner is less than 5 watts.

So I expected 8 or 10 hours of use (as least as much as AA batteries would last), if not a lot more. So I plugged my Uniden 996T scanner into it, and let it "run out" to see how long it would go on the APC battery itself.

It went 2 hours and died!!

Does this mean my APC is basically dead? Or am I not doing something right?

If it should last 1:20 on 50 watts, I would expect a lot more from just a scanner.
 

mass-man

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YEP...your APC is dead!!!

The batts inside just don't last forever, or in your case five years!!!

Time for a new one-------
 

hiegtx

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kc8qln said:
I have a small 3 year old APC backup I was just using on a cheap TV. The model number is ES-725. The spec for the ES-725 shows 1 Hour 20 Minutes with 50 Watts. But, I am sure the scanner is less than 5 watts.

So I expected 8 or 10 hours of use (as least as much as AA batteries would last), if not a lot more. So I plugged my Uniden 996T scanner into it, and let it "run out" to see how long it would go on the APC battery itself.

It went 2 hours and died!!

Does this mean my APC is basically dead? Or am I not doing something right?

If it should last 1:20 on 50 watts, I would expect a lot more from just a scanner.
You have several things working against you for getting 8-10 hours of use.

First, look at the power supply for the 996. What is the amperage output? (It should be expressed in milliamperes, or abbreviated as "ma". And the voltage? The one for it's closest digital relative, the BCD396T, is rated at 800ma, or .8 amps. At 6 volts nominal operating output, that might be 5 watts output. But wall warts are not 100% efficient. Some of the power comsumed is lost as heat. Your hand will tell you that. So actual power consumed will be more.

The 996, I presume, takes a 12v output adapter. Multiply the power output (in amps) by the nominal voltage, presumably 12v. I'd add at least 25% to that figure for inefficiency. I would imagine it's power requirement is greater than the 396, as it has a more robust processor, greater audio volume, and a larger display (with more backlighting).

Your APC supply is also not 100% efficient. It stores power in one or more battery cells. But to turn that back into usable ac current, it has to use an oscillator to convert the dc power from the battery into ac, so that the voltage can be stepped back up to normal ac line voltage. Again, some of this energy is lost as heat in the process.

Lastly, at three years old, it's likely that one or more of the battery cells may not be holding their full charge anymore. This you could address by purchasing replacements at a battery specialty store or from an APC dealer.

For another thread along this line, with a couple of alternate suggestions. see this.
 
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I have tried it with my APC backup. I believe its a ES-350 would have to look at it to be sure but I only get around 1 1/2-2 hrs out of it with either my 996 or my 2006. The APC is only about 7 or 8 months old
 

kf4lne

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Those things are really only good for a few minutes under maximum load. If you want to power your scanner for extended periods i would suggest investing in a gel-cell and trickle charger and appropriate cables to power the scanner. Most scanners come with a 12VDC wall-wart with a standard plug on the end, you can usually pick up those plugs at Radio Shack and you can use just about any wire of at least 16 guage (maybe even smaller) to connect the radios with. Check around at hamfests for batteries, you can usually find them in large piles that came from a hospital, many times in great condition since the back up batteries used in hospital equipment has to be changed regardless of condition on a regular schedule.
 

Al42

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kf4lne said:
Those things are really only good for a few minutes under maximum load.
Battery backup is battery backup. I get more than 12 hours on an 1100 watt/15 minute backup when it's lightly loaded (cordless phone, cable modem, wireless router). 1100 watts/15 minutes is 275 watthours, almost any way you look at it, so a 20 watt drain will last for over 12 hours. And the little switching wall warts, if heat is any indicator, are very efficient.
 
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