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Battery for CG5-GT

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#1 astrocy

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Posted 01 February 2010 - 10:42 AM

I am thinking to buy a 12V battery to power a Celestron CG5-GT mount, but I am not sure what to get. The battery will be used for 3-4 hour sessions and I am estimating a GoTo every about 5 minutes. Possible choices are 7A, 9A, 12A, 18A, but battery weight is also a factor to consider.

#2 rmollise

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Posted 01 February 2010 - 11:15 AM

If you are really gonna be goin on go-tos every five minutes, you will want the 18ah.

#3 RTLR 12

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Posted 02 February 2010 - 12:25 AM

I get about 3 1/2 hours of active use from my 7ah battery and about 7 hours from my 18ah battery. That's just running the scope without any accessories. After that, even though the voltage is sufficient while tracking, the voltage drop when slewing is not enough to properly power the mount. The result of which is error codes such as "NO RESPONSE 16 or 17" which result in inaccurate GO-TO's or "PRESS ENTER TO START ALIGNMENT" in which case there is a loss of alignment.

Stan

#4 astrocy

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Posted 04 February 2010 - 11:56 AM

Should I charge the battery after each use regardless the duration of the session? If I don't use it for a long period should I charge it and how often?

#5 Eddgie

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Posted 04 February 2010 - 12:31 PM

Some may depend on the type of battery, but for standard sealed lead acid gel types, you should fully recharge after every use.

Think about a car battery. Once you start the car, the alternator IMMEDITALY starts recharging the battery, and they will last thousands of cycles.

The chemicals will die from old age (3 to 7 years) before the battery dies from the amount of charge cycles. Again, think car battery.

The problem though is that I have bought 7 amp batteries from these dedicated battery stores to use in things like electric string trimmers (I am a greenie), and they would often only last a year or two.

I had a battery in my lawnmower that was made by Panasonic (2 actully, for 24 vdc). Those batteries ran my lawnmower for SEVEN YEARS! And I have LONG growing seasons. These batteries would power the lawn more for 30 to 40 minutes even cutting tall grass.

Of course the batteries cost $65 apiece, but after seeing how long a really excellent lead acid seald battery COULD last, I stopped buying my batteries at battery stores. I now order them on the web. I pay more, but my batteries last twice two three times as long.

Regards.

#6 Patrick

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Posted 05 February 2010 - 02:04 PM

I use a 33 amp hour wheel chair battery which is a good amount of power yet is nice and portable.

Should I charge the battery after each use regardless the duration of the session? If I don't use it for a long period should I charge it and how often?



Yes, it's very important to keep your batteries charged up after each use and also if you don't use them in a while. I try to put the charger on my batteries at least every 6 weeks over winter if I'm not using them. The best way to ruin a good battery is to let it discharge over time.

Patrick

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#7 rapdas

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Posted 05 February 2010 - 03:57 PM

Is there a cheaper battery option out there than the Orion's Dynamo which goes for about $90? It has a number of extras like the FM player and the halogen light which i do not need so i figure there may be cheaper bare battery options out there.
My mount requires 12V DC at 2 amps and i would like a session to last about 3 hours.

#8 Chris Rowland

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Posted 05 February 2010 - 05:35 PM

Shouldn't that be Spinach?

#9 Patrick

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Posted 06 February 2010 - 12:35 AM

i figure there may be cheaper bare battery options out there.
My mount requires 12V DC at 2 amps and i would like a session to last about 3 hours.



A 33 amp hour wheel chair battery like I posted above can be purchased for $60-70. Add a Radio Shack alligator clip/cigarette light DC power connector and you're all set.

Still too big? I've shopped around quite a bit for batteries, and this size is pretty good. You can get 5 amp hour batteries, but I wouldn't recommend them when it comes to recharging them.

Patrick

#10 Astroforecast

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Posted 06 February 2010 - 02:09 AM

I use a 90 Amp-Hour marine deep cycle battery that I already had on my boat. You can get them at a sporting goods store on sale for about $40-90 depending on size. I've discharged mine completely many times over a two year period and its still going strong. Just be sure to fully recharge it as soon as possible. Otherwise you'll get sulfation on the internal plates and the battery won't take a charge. A small charger will run an additional $25+ depending on charge rate and other features.

Here's a 23 Amp-Hour for $45 at Academy
http://www.academy.c...0105-00150-1478

#11 rapdas

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Posted 06 February 2010 - 10:10 AM

Cool! Thanks guys :)

#12 Joe Lalumia

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Posted 06 February 2010 - 06:07 PM

Really cannot beat those marine deep cycle batteries-- they run trolling motors all day long to almost complete discharge. Optima always gets good reviews in boating magazines- there is a blue top and a yellow top-

http://www.cabelas.c...0007&hasJS=true

Here are some customer comments:
http://www.eham.net/...ews/detail/6774

Buy the blue top version-- for deep cycle. It's the one everyone uses in boating applications. Expensive- Pat's battery is also a good one.






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