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600-800mA seemed too low to me, assuming that the mA's are per-motor, plus some overhead for the PMC8 itself.
So... I decided to perform a test of incrementally adding and removing load. The only convenient tool I have to measure with is the amps reported by my Pocket Powerbox's control applet. So yes, this is a system measuring itself, and probably in 0.1A increments. So no great precision, but still, I think, good enough to reflect incremental changes.
I did two iterations and got the same results from each. I did not try a slew, just tracking.
With only the Powerbox and Anker USB hub (powered) connected, 0.1A reported
Connect PMC8 and its motors, 0.9A to 1.4A lo/hi reported, rapidly changing, with most values between 1.1 and 1.3A
Disconnect the DEC motor only: 0.6-0.9A lo/hi, less rapidly changing, with most values 0.7 to 0.8A
Disconnect the RA motor as well (ie: just PMC8 + USB hub overhead): 0.2A steady
Connect the DEC motor: 0.6-0.7A lo/hi
Connect the RA motor: 0.9-1.4A lo/hi, and again most values are in the range of 1.1-1.3A
Again, no great expectation of laboratory precision here, but it looks to me like (2x600)+100 = 1300mA (fluctuating) would be closer.
What do you think?
On Sun, Aug 23, 2020, at 22:53, Jerry Hubbell - Explore Scientific VP Engineering wrote:
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