|Forum topic by Thuzmund||posted 01-19-2015 10:51 PM||4072 views||3 times favorited||38 replies|
01-19-2015 10:51 PM
After days and days of research, I’m tossing out a couple questions that I just couldn’t find answers to. I’m researching the DC Treadmill motor lathe conversion. Looks like it’s worth the 150 bucks or so to give it a try for my needs—safely turning out of balance pieces and coring with a little more power than my current 3/4hp motor has. I have seen at least four different threads on this topic here at LJ…but no answers to the following questions.
1) Lots of motors on ebay are listed at amps or volts beyond what I think I can supply. My residential service is 110 (or 115/120…haven’t actually measured the darn thing) VAC, 15 amps. I’m aware that 15 amp circuits can supply more than 15 for short periods of time, but I am naturally afraid of running, say, a 18 amp motor on my 15 amp line for several hours. Beyond this, many motors only give volt ratings, like “1.5hp at 95VDC.” More confusion for me.
Now, to supply DC voltage I must use a controller box that converts to DC and supplies (and therefore limits?) juice. Therefore, am I correct in assuming that I can avoid overloading my house wiring by using a a controller that supplies a safe amperage?
2) What happens when the motor runs at lower amps than it is rated for (let’s say an 18 amp motor)? I’ve read that it will heat up and die prematurely, but after shopping around for treadmills, I see that many many treadmills with 2.5 or 3hp motors have normal 120V power cords and say nothing in the manual about using 20amp service. They do say you must use a power strip (circuit breaker) for safety. This means that thousands of treadmills are running the exact same setup as I’m imagining—a motor running under amperage but prevented from drawing an unsafe amount of juice. These treadmills must not be burning up left and right. Is it safe to assume that I can run a motor for many years under the rated amps on the nameplate?
3) Last question: Will my house 110VAC actually be able to provide 110VDC after the conversion, or is voltage lost during the rectification process? I’ve seen sources saying both—some say I can only get 75% of the voltage at DC and others saying it will be a 1-to-1 conversion. Any ideas on what type of DC voltage I can expect from a DC controller plugged into my wall?
Thanks in advance. I’m trying to decide between motors listed at 1 or 1.5hp around 10-15amps, or 2 to 2.25 hp rated around 16-18 amps. All of these are “peak figures” and the nameplates say that they will run continuous duty around 90VDC, with a loss of about 30-50% of hp.
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