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Battery Power for EXOS-IIGT with PMC-Eight


Robert Parks
 

My mount did not come with any battery pack; bought in-house at ES.  Lance advises it no longer ships with a d/c battery pack.  Question: what is the recommended way to "remote power" when one is away from an A/C power source.  

I searched the posts and haven't seen this topic directly addressed, but I'm new to Groupsio so I apologize if this is repetitive.

Scott


Keith Krayanek
 

Scott,

I called when I realized the same thing.  I called ES told them there was no battery pack and they sent me for their older Bressor mount.  Of course the tip is a different size.  And I did not realize the tip was a different size from the ac corded tip.  I measured the battery pack tip  and got a tip for that and hooked it up to a 12 v marine battery.  Worked fine until the day of the solar eclipse.  Being in North GA I was getting a full solar eclipse.  About an half hour before full totality the mount stopped working.  The PMC-Eight locked up and the mount would stop tracking.  If you just touched the wire I could reproduce the same symptoms later on.  I should have noticed that the battery pack tip was a different size from the supplied A/C tip.  Then again so should have customer service at ES known that.  But they tried and that is more than some other companies.  

I did get the mount early, I exchanged my older Bressor Mount for the EXOS-II Mount with ES.  

Get yourself a  5.5mm/2.1mm DC tip and some wire and a 12 v battery.  Make sure you make the tip positive.  This is the correct size for the PMC-eight, exact size of the A/C tip.  Do not know if there any safeties in the PMC-eight, so be very sure you plug in the tip to the positive of the battery.  You do not want to reverse the polarity.  

Hope this helps

Keith Krayanek 


Steve Siedentop
 

I believe the PMC8 has reverse polarity protection.  As the PMC8 uses the "standard" 5.5 x 2.1mm center positive plug, you'll find options readily available.

Note to Jerry:  I'd like to see ES include at least a DC power cable as that's what the competition is doing and these mounts will be judged against competing products in the same price class.

That being said, a Celestron power cable will work just fine.  I made my own using Anderson Power Poles.  I also made my own battery box for less than $100 including the deep cycle battery.  If you don't need something that big, there are plenty of 12 volt battery options.

  I'll dig out a parts list when I get home.



-Steve


Steve Siedentop
 

Keith -

Do you live in Georgia or were you visiting for the eclipse?

-Steve


Wes Mcdonald
 

At the AHSP the issue of polarity protection came up with Jerry.  The PMC8 is indeed protected.

I found the cable for my Meade LX200 is correct for the PMC8 also.  I had two (one is none) so that worked out well for me.

If you make your own power tank be sure to fuse the thing.  

Wes

On Tue, Sep 18, 2018 at 6:19 PM Steve Siedentop <sdsiedentop@...> wrote:
I believe the PMC8 has reverse polarity protection.  As the PMC8 uses the "standard" 5.5 x 2.1mm center positive plug, you'll find options readily available.

Note to Jerry:  I'd like to see ES include at least a DC power cable as that's what the competition is doing and these mounts will be judged against competing products in the same price class.

That being said, a Celestron power cable will work just fine.  I made my own using Anderson Power Poles.  I also made my own battery box for less than $100 including the deep cycle battery.  If you don't need something that big, there are plenty of 12 volt battery options.

  I'll dig out a parts list when I get home.



-Steve


Wes Mcdonald
 

One last thing.  The PMC8 draws about .5 amps sitting there tracking at sidereal rates on an Exos II.  Don't know what the peak current is.  5 amps should be sufficient for a fuse.

Wes

On Tue, Sep 18, 2018 at 6:40 PM wes McDonald <wesmcd6@...> wrote:
At the AHSP the issue of polarity protection came up with Jerry.  The PMC8 is indeed protected.

I found the cable for my Meade LX200 is correct for the PMC8 also.  I had two (one is none) so that worked out well for me.

If you make your own power tank be sure to fuse the thing.  

Wes

On Tue, Sep 18, 2018 at 6:19 PM Steve Siedentop <sdsiedentop@...> wrote:
I believe the PMC8 has reverse polarity protection.  As the PMC8 uses the "standard" 5.5 x 2.1mm center positive plug, you'll find options readily available.

Note to Jerry:  I'd like to see ES include at least a DC power cable as that's what the competition is doing and these mounts will be judged against competing products in the same price class.

That being said, a Celestron power cable will work just fine.  I made my own using Anderson Power Poles.  I also made my own battery box for less than $100 including the deep cycle battery.  If you don't need something that big, there are plenty of 12 volt battery options.

  I'll dig out a parts list when I get home.



-Steve


Peter Turner
 

Just checked and the tip for the Celestron Power Pack fits.


Thomas O
 

Hi All,

I am looking at buying this tripod and mount and will occasionally walk to the park near my house to use so AC won't always be available.  My question is, would a 12v battery with up to 7AH and a 200w power inverter get the job done for this rig?

Below are links to the products

https://www.batteriesplus.com/productdetails/SLA12=7F?locationofinterest=&locationphysical=9012387&gclid=Cj0KCQiA8f_eBRDcARIsAEKwRGf4dl97XxpvT9K8GOKQGqlslre22QD-MJrddhbtuMib-WGcteCy-58aAgS1EALw_wcB

https://www.amazon.com/Power-Bright-PW200-12-Inverter-Watt/dp/B000NP30HC/ref=sr_1_60?s=automotive&ie=UTF8&qid=1541455129&sr=1-60&refinements=p_n_feature_keywords_browse-bin%3A11437820011

Thanks for the feedback


Wes Mcdonald
 

Tom:

You don't need to use an inverter, you can power the mount directly from a 12V battery.  I run mine from a deep discharge marine battery with ridiculous capacity, just because. I had it.  My Battery Monitoring Unit indicates the PMC-8 draws a quiescent current of about .5A.  Thus a 7AH battery would theoretically last 14 hours.  I wouldn't want to run it that way though, probably need to limit the discharge to 50% or so which is 7 hours.  Then you will be eventually, or now, wanting to add dew control for the scope which is big consumer of energy, say about 1A per strap.  Say a total of 2.5A.  Now we are getting down there in usage time. 

Recommend you go with some kind of auto/marine lead acid battery.  Put it into a battery box, and wire in some cigarette lighter sockets with fuses.  Provide a means for attaching a battery charger, buy a charger.  An on/off switch is a bonus.

Wes.


Paul Shirley
 

I am a new owner of the Exos with PMC-8, so take this for what it's worth. My first light with the mount was Saturday night, and I powered it with a Talentcell rechargeable Li-on power bank with a 12v 5amp usb port (11000mah), and also with the 8 D power pack that came with my original Exos-2GT. I had alignment issues initially (that were not battery related), and was constantly slewing for the first three hours. Total time I used the mount was about 4.5 hours. Both worked fine. What did not work was a jumpstarter with a usb port that put out a maximum of 3.1A. I found this out when I first un-boxed the mount. BTW, afterward the 8 D battery pack was still at 11.8 volts.

Since the D cell battery pack will go with the Exos-2GT when I sell it, I have since purchased a Dura-Cell portable power pack from Costco with a 12v plug receptacle. I will try that as soon as the clouds clear this week. 

Disclaimer: I am visual only, don't run anything else but the scope.


Thomas O
 

Wes,

Thank you very much for your detailed recommendations, much appreciated!


Jeremy Parker
 

Hi All,

Maybe some will find this useful... I got a Celestron PowerTank Lithium (the smaller one) for my ES G11, initially just to use for visual use for impromptu star parties, and it could power the mount easily overnight, plus add enough red/orange ambient light around the mount to prevent people from bumping into it.

Any standard 2.1mm X 5.5mm female to female cable should work for connecting to the PMC-Eight, like this one from Amazon:
https://www.amazon.com/gp/product/B01BKSZ7NA/ref=oh_aui_detailpage_o03_s01?ie=UTF8&psc=1

The LiFePO battery technology that is used in these latest Powertanks is very good for this application, if you can justify the higher cost. It holds the output voltage for longer before dropping, and does better with cold temperatures compared to other battery types. And it can be recharged about twice as many times as typical LiPo batteries.The only other downside to the smaller Powertank is that you can only use the 12V outlet OR the USB outlets, not both at the same time. So I just got the Powertank Lithium Pro (the larger one), which does let you use the two 12V outlets and the USB simultaneously. I bought a 12V to 9V DC-to-DC converter off Amazon, and made an adapter to power my Nikon D5300 off the bigger Powertank.
 
My Microsoft Surface Pro runs off 12V already, so I found a 2.1mm X 5.5mm power cable for it:
With those items and a couple 2.1mm X 5.5mm Y-cables, I can completely power my rig off the batteries. Based on some initial testing indoors, I think I can get a night's worth of imaging in at a remote site (depending on how much I turn my dew heaters up). The smaller Powertank was only powering the ES G11, and it had plenty of juice left in it by morning. So I may use a 12V Y-cable to connect both the mount and D5300 to the smaller Powertank, leaving the computer power, USB hub, and dew heaters to be handled by the Powertank Pro.

I do also like the idea of a single customized battery box, and fused connections, as well as products like the Pegasus Astro Pocket Powerbox which looks very slick and could also take the place of my dew heater controller:
https://agenaastro.com/pegasus-astro-pocket-power-box.html

But I will step into the more serious solutions after I get some time in at remote sites with what I have now...

Regards,
Jeremy


Peter Turner
 

I use the Celestron Power Tank.  You can get it from lots of places.  Here's a link to one: https://www.adorama.com/cnpt.html?gclid=CjwKCAiAt4rfBRBKEiwAC678KbbjBQkidiJbIVTXsFqLaa32_IQHWNNQJGp6cJ3yHMZHTs2bjzXUkRoC6UIQAvD_BwE  It lasts for multiple multi-hour sessions.  It will also recharge your car battery if that goes out will your at a dark site.  I highly recommend it.

Pete


Jason Haefner
 

Celestron Power Tanks are the biggest rip off IMO.  They give you a $20 dollar battery and the shell is completely unnecessary.  The batteries aren't deep cycle either from what I understand.  They are rebadged car jump starters.  A better alternative is a $35 for a 18AH deep cycle or bigger depending on what you need or want to spend..  $30 for anderson power pole connectors.  ATC Style Fuse Holder 10 GA with Ring Terminals and Powerpole Connectors  & 2.1mm Straight DC Coaxial Power Plug to Powerpole Adapter 6 ft.  from powerwerx.com


Tim Robertson
 

I have the Celestron Power Tank that I use with my other mount without issues, I tried to run the PMC-Eight with it and it I got no power light. I will need a portable power source for this controller. Watching this thread.

Tim


Peter Turner
 

I first started using the Celestron Power Tank with my Celestron CG5-GT mount.  I seem to remember some posts on Cloudy Nights about having to fiddle with the mount's connector (in your case PMC-8.  I don't remember if I had to do those fiddles or not with the CG5 When I got my CGEM mount it was nice because it came with an adaptor screwed into the mount so made a great connection.  However when I sold that mount I sent along that connector, so am back to my original one that came with the Power Tank.  I have no problems powering the PMC-8 with it.  Take a look at this post on CN, the third or fourth response discusses what I'm talking about.


Tim Robertson
 

Thanks for the tip on the TalentCell- I picked one up on Amazon and it is working great! Prefect size and power.

Tim