Some results:
I've been running the motor in the original photos with one fan as a temporary "air mover". Itr draws .66A, 79w, with 120v across the green and red wires. I assume it's turning 3100rpm, give or take.
My motor run caps arrived. I experimented with various caps in series on the green supply wire. Results:
4uF - motor would not operate.
8uF - motor would start only with help, turning less than 60rpm, .61A, 9w, erratic voltage readings.
15uF - self-starts without help, turns ~250rpm, 1A, 29w, 32v. Too slow for my needs.
20uF - self-starts, turns ~500rpm, 1.3A, 49w, 44v. Perfect speed. Quiet, slow air mover.
30uF - self-starts, hiccups as it reaches top speed, 1.8A, 106w, 82v. Too fast. Also using more power for less rpm.
I didn't notice any rapid heat buildup, but I only ran each combination for a minute or less.
Pretty cool. Thanks rossw!
I have a few other questions:
I bought some smaller motors, $4 each. They fit the fan housing perfectly.
Label:
117v 60hz 1140rpm Cont
65v 50hz 950rpm CONT
Type: KPT, HP 1/40, PH 1
The paperwork that came with the motor calls for a 25uF 370vac run capacitor.
I don't have a 25uF. I tested the motor with my 8, 15, 20, and 30uF caps.
8 - .13A & 16w slow.
15 - .34A & 32w perfect speed.
20 - .56A & 51w faster.
30 - 1A & 105w faster still.
This motor is perfect for my air moving job with the 15uF cap, but it calls for a 25uF cap.
Will I be shortening the life of the motor if I elect to use it with a 15uF run cap?
Also - the motor has oil holes. What type of oil? Coupla drops enough?
Lastly, the wire diagram says:
L1 to white
L2 to blue
L2 also to cap in series to paired green and black.
It works in this configuration, but I guess there's no ground?
Thanks!