Speed control for 230v motor

CNCman · May 10, 2023

I'm a DIY'er. Setting up a dual purpose shop-cooling and overspray fan. Bought this motor which reads "1.5 hp" but, looking at the amps, shouldn't it really be closer to 3hp? Anyway, I'd like to be able to slow it down occasionally because it will knock you off balance to walk in front of it. * I have the safety grate removed only to take photos of the motor's spec plate. Used it for the first time, yesterday, to remove overspray and It did so very quickly. Have it wired 220v right now. What type speed control do I need? Thanks

CNCman · May 12, 2023

What about a Variac? 20Amp Variac 2000VA 0-230V Transformer Variable AC Voltage Regulator Metered 840281556571 | eBay - https://www.ebay.com/itm/165656098755?hash=item2691df77c3:g:VUEAAOSwN6ZjEglr&amdata=enc%3AAQAIAAAAwFJ4AsY%2BnTIA7R4AeuM%2FPy3Hj%2FKQxA%2BUfWNnJZ1Z9r3iUPEH6i7DPS60ohcz7QV6ULZhYhcbeoDrfDFArWAhc6nsw0iTzLsL4xe32%2BvFrZXn0C85c186KkBk5TKkzzn7drAbSFmHfla4KiJr9dRUHV0Qs7ev0wQI30K2uZo%2BWHEvab6tpnZ1rFrmiTQK6C4lG%2F2BBKYV6mYjif44sAPozfo5yoQjOTwbyWAyuO%2F45riBvUr81tg2QjVIClcDDkBkXw%3D%3D%7Ctkp%3ABk9SR8qTh4aCYg

James · May 12, 2023

try a bigger pully on the fan end of the belt.

Marvo · May 13, 2023

CNCman said:
I'm a DIY'er. Setting up a dual purpose shop-cooling and overspray fan. Bought this motor which reads "1.5 hp" but, looking at the amps, shouldn't it really be closer to 3hp? Anyway, I'd like to be able to slow it down occasionally because it will knock you off balance to walk in front of it. * I have the safety grate removed only to take photos of the motor's spec plate. Used it for the first time, yesterday, to remove overspray and It did so very quickly. Have it wired 220v right now. What type speed control do I need? Thanks

This is a common misconception, the horsepower (or kilowatt) rating given on a motor refers to the amount of mechanical work it can do. Because of this the current draw of a motor will always be higher than the figure you calculate from its power rating due to inefficiencies such as noise and heat energy it produces whilst running.