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Power source for EM-200

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#1 Hypnotist

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Posted 27 January 2011 - 04:28 PM

Hi,
I've been using a car battery to power my EM-200 but I don't like it because of its weight (and I have to return it to a friend of mine sometime soon). Does anybody have an idea what battery I should get?
:help:
Thanks and clear skies
Bart

#2 Jwemes

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Posted 27 January 2011 - 05:10 PM

If weight is your prime issue, you might consider a motorcycle battery. However, if your EM-200 is a Temma, and you slew to a large number of objects during an evening, you might really need a power source that can deliver like an auto battery. I use a group24 in a battery box, and it will drive my non-Temma NJP motors for several nights with no problems.

#3 Planemo

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Posted 27 January 2011 - 08:03 PM

Go to wallyworld and buy a 75amp hr. marine deep cycle battery for about $60. It will run the mount and dew control for several nights.

#4 Dwight J

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Posted 27 January 2011 - 10:31 PM

Hi Bart: I use a gel cell 35 AH battery - it will power the mount for a couple of nights depending on how much slewing you do. I actually bought two of them so I can utilize the 24 volt faster slewing aspect of the mount. They are quick to recharge and lighter than lead-acid batteries. Mine are 5 by 7.75 and 6 inches high. I bought them at a local battery supply store for $70 each.

#5 Hypnotist

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Posted 28 January 2011 - 11:22 AM

So you're telling me there's nothing like Celestron's power tank for EM-200 Temma II mounts?

#6 jrcrilly

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Posted 28 January 2011 - 11:29 AM

So you're telling me there's nothing like Celestron's power tank for EM-200 Temma II mounts?


You can certainly operate a Tak mount with a Power Tank (I've done it). Most of us, however, prefer to operate these mounts at 24VDC.

#7 LLEEGE

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Posted 28 January 2011 - 03:42 PM

I could be wrong, but I think the newer Tak mounts will slew at 700x with only 12v. Hard to figure out from the ad literature.
You can wire two Powertanks in series to get 24v if that is not he case or you need 700x slew rates.

#8 Hypnotist

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Posted 28 January 2011 - 05:09 PM

Do you have a link for the powertank?

#9 LLEEGE

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Posted 28 January 2011 - 06:15 PM

This is what I use for my mounts. It works well with the 900 and 1200.

#10 LLEEGE

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Posted 28 January 2011 - 06:16 PM

What I like about it is it has 2 12v ports. One for the mount and one for the dew heaters.

#11 Lew Chilton

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Posted 28 January 2011 - 08:09 PM

Do you have a link for the powertank?


Bart,

OPT is near you in nearby Oceanside. It carries the Celestron Powertanks. But there are better options than the Powertanks, as mentioned in this thread. In my opinion, your scope needs a larger capacity battery than the Powertanks can provide, unless you gang them up in parallel.

#12 Poochpa

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Posted 29 January 2011 - 08:13 PM

Careful here. The older EM-200 Temma II can operate at 12v or 24v (24v for faster 700x slews). The new version, the Temma-2M, is 12v only (700x) and will be damaged by a 24v battery.
Mike

#13 Lew Chilton

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Posted 30 January 2011 - 11:58 PM

Careful here. The older EM-200 Temma II can operate at 12v or 24v (24v for faster 700x slews). The new version, the Temma-2M, is 12v only (700x) and will be damaged by a 24v battery.
Mike


Mike, I'm not sure if you're referring to my post or not.

If you hook up two batteries of equal voltage and capacity in PARALLEL, the combination will produce the same voltage but double the amp/hr. rating.

If you hook up the same two identical batteries in SERIES, you will double the voltage but retain the same amp/hr. rating.






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