Thanks for the offer and confirmation! I probably should stick with GA firmware, though.  Yes, the numbers I mentioned were just tracking, not slewing.  Very odd - I remember the earlier bump up, and I think I even did a bit of testing on one you were trying. 

Anyway, if all is as intended, then I'll just roll with it and figure out how to augment my power. 

Out of curiosity, though... did the amperage range I found look reasonable to you, considering the power consumption of the PMC8 itself, PLUS the steppers?

- Bob

On Sun, Aug 23, 2020, at 16:38, Jerry Hubbell - Explore Scientific VP Engineering wrote:
On Sun, Aug 23, 2020 at 02:54 PM, Robert Hoskin wrote:

So... basically just asking you to confirm that power consumption defined in firmware for both tracking and slewing really is as intended, and a heads up for you on possible battery run time impacts. 
Hi Bob, thanks for the feedback.  For the EXOS 2 I changed the current from 600 mA (tracking and slewing) in 9T10/11 to 700 mA (tracking and slewing) in 9T13/15 and then in 9T17 to 600 mA (tracking) and 900 mA (slewing). I have confirmed these numbers in the firmware code.

If you are mostly tracking then the motor current should be the same as you saw in version 9T10/11.  I can send you a custom firmware with only 600 mA if you like to compare. I increased the motor current during slew so that it would overcome more inertial load and also overcome a little more imbalance. Let me know what you would like to do.
Jerry Hubbell
Vice President of Engineering
Explore Scientific, LLC.
jrh at
1010 S. 48th Street
Springdale, AR 72762

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
: 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!

Mounts: ES PMC-8 EXOS2
Scopes: SV 102EDT, ZWO 60/280 Guide
Cameras:  Nikon D5300, Altair GPCAM2 290M
Software: ASCOM, CdC, AstroTortilla, BYN Pro, Sharpcap, PHD2
Computer:  Thinkpad x230, Win7Pro/64

Join to automatically receive all group messages.