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Using 1.2 V NiMH batteries #iEXOS-100


Mehdi Tlili
 

I would prefer using rechargeable batteries in my IEXOS but the problem is that the NiMH batteries have only 1.2V, resulting in a total voltage of 9.6V when put in series compared to 12V when using classical alkaline batteries.
Would that affect the tracking performance or damage the motors? Or is there a voltage regulator built in?


Chris Tardif
 

The mount will chew through rechargeable batteries.   If you're taking it to the field then get one of those larger powerbank / powertanks.  If its in the back yard, get a 12v power supply and an extension cord.  I bought a 12v PS off amazon 18 months ago and haven't looked back.
--
Mounts: Explore Scientific IEXOS-100 w Celestron CG5 tripod, iOptron CEM 40
Scopes: Explore Scientific FCD-100 ED-102CF, Various Canon lenses, ZWO mini-guidescope, StarField 60mm guide-scope.
CameraASI120MM Mini (mono), Altair GPCAM 130
Control PC: Intel NUC
Loc: 44 -79


Mehdi Tlili
 

Thanks for the feedback. Any idea on how much current it pulls while star tracking and while moving to a given position?


Jerry Hubbell - Explore Scientific VP Engineering
 

On Mon, Aug 24, 2020 at 09:01 AM, <mehdi.tlili@...> wrote:
Would that affect the tracking performance or damage the motors? Or is there a voltage regulator built in?
Hi Mehdi,  thanks for you questions.
The PMC-Eight requires a nominal 12 VDC power supply. The internal voltage regulators for driving the motors are 10 VDC. The minimum voltage for the system where anything less than that is about 10.6 VDC. Any voltage below this will cause the motors to not provide enough torque and the system would fail. This doesn't impact the controller, or WiFi communications, only the motors. So the 9.6 VDC would definitely not work. If you want to use the rechargeable NiMH batteries, you would need to have at least 10 of them in series, and I would suggest 11 for more margin. The PMC-Eight will work fine with input voltages from 12 - 16 VDC. If you decide to build your own battery pack pay close attention to the connector polarity. The center pin is positive with the outside barrel negative. There is reverse polarity protection on the system, but it is best not to challenge it.
 
--
Jerry Hubbell
Vice President of Engineering

Explore Scientific, LLC.
jrh at explorescientific.com

www.explorescientificusa.com
1010 S. 48th Street
Springdale, AR 72762
1-866-252-3811

Author: Scientific Astrophotography: How Amateurs Can Generate and Use Professional Imaging Data
             Remote Observatories for Amateur Astronomers: Using High-Powered Telescopes From Home


Mark Slade Remote Observatory (MSRO) IAU MPC W54 Equipment
Wilderness, VA
Mounts
: ES PMC-Eight G11 + Telescope Drive Master (TDM)
Scopes: ES 165 FPL-53 ED APO CF, ES 102 FCD100 ED APO CF
Cameras:  QHY174M-GPS + FW, QHY163C
Misc: 3-inch 0.7x Focal Reducer Field Flattener, Filters: Luminance,
Red, V-band Photometric, Diffuser, 200 lpmm Spectral Grating

Software: MaxIm DL 6, Cartes du Ciel, Astrometrica, AstroImageJ, AutoStakkert!


Harry
 

Hi Mehdi, I also have the iExos100. I now use the Explore Scientific USB Power Bank. Its small, light weight, and fits perfectly in the iExos stock plastic battery pack holder. I power the mount, and a couple of dew heaters, and it will last at least several hours. I have been outside for 2-3 hours, and it is still around 75-80 capacity (estimated). It also has a red light that I use to illuminate the area under the mount.
--
Harry
Vero Beach, FL

Mounts: ES iExos 100-PMC Eight, ExploreStars iPad, Fire HD8
Scopes: ES  ED80CF, ES AR102,  Meade ETX 90 EC (Deforked)
Software: MacOS, Starry Sky Stacker, Affinity Photo, Lightroom,  SkySafari Plus
Cameras: Nikon D600, D5500
Misc: ES USB Power Bank, Rigel QuikFinder, 0.8x Focal Reducer, Filters:
 Optolong L-Pro, L-eNhance





Shailendra Sharma <sshailendrasharma@...>
 

This exactly what I wanted. But difficult to get in the uk. So settled for the skywatcher 17ah tank.


From: MAIN@ESPMC-Eight.groups.io <MAIN@ESPMC-Eight.groups.io> on behalf of Harry via groups.io <flykai1@...>
Sent: Monday, August 24, 2020 4:08:48 PM
To: MAIN@ESPMC-Eight.groups.io <MAIN@ESPMC-Eight.groups.io>
Subject: Re: [ESPMC-Eight] Using 1.2 V NiMH batteries #iEXOS-100
 
Hi Mehdi, I also have the iExos100. I now use the Explore Scientific USB Power Bank. Its small, light weight, and fits perfectly in the iExos stock plastic battery pack holder. I power the mount, and a couple of dew heaters, and it will last at least several hours. I have been outside for 2-3 hours, and it is still around 75-80 capacity (estimated). It also has a red light that I use to illuminate the area under the mount.
--
Harry
Vero Beach, FL

Mounts: ES iExos 100-PMC Eight, ExploreStars iPad, Fire HD8
Scopes: ES  ED80CF, ES AR102,  Meade ETX 90 EC (Deforked)
Software: MacOS, Starry Sky Stacker, Affinity Photo, Lightroom,  SkySafari Plus
Cameras: Nikon D600, D5500
Misc: ES USB Power Bank, Rigel QuikFinder, 0.8x Focal Reducer, Filters:
 Optolong L-Pro, L-eNhance





Yorksman
 

I got hold of some Panasonic Alkaline batteries but the mount failed very quickly. I thought it was a fault. Then I noticed the batteries said 'for low powered products'. Got some duracels and they ar still working. More expensive of course but you do need to deliver enough power constantly.


Brian Ginn
 

You may want to take the batteries out every time you are not using them.

My experience with Duracell's is that they leak far too often.

I've been buying Costco's Kirkland brand and haven't had a leak so far.





--
Brian
Thousand Oaks, CA

Mount : ES EXOS-2GT PMC-8
*Controller* : (ExploreStars, Android 8.1.0, 10" Samsung Tab A)
Scope : ES ED80 f/6 Triplet
Camera : Canon 6D


Brian Ginn
 

I was referring to alkaline batteries, not NiMH.

Also, I don't have the iEXOS 100, so I cannot speak as to how they operate in that.

On 8/24/2020 2:20 PM, Brian Ginn via groups.io wrote:
You may want to take the batteries out every time you are not using them.

My experience with Duracell's is that they leak far too often.

I've been buying Costco's Kirkland brand and haven't had a leak so far.




--
Brian
Thousand Oaks, CA

Mount : ES EXOS-2GT PMC-8
*Controller* : (ExploreStars, Android 8.1.0, 10" Samsung Tab A)
Scope : ES ED80 f/6 Triplet
Camera : Canon 6D