HP calculations?....

Mark Rios

Member
Messages
797
Location
Central CA
No HP listed on motor info sticker. This is an Emerson electric motor on a Table Saw

Specs are:

120V or 240V

Amps 13/6.5

RPM 2850/3450

Can someone kindly tell me the HP, please?

Thanks very much for your time.
 
Thanks Don. The 2HP was what I got as well. But I didn't have any idea about how to factor the efficiency or even what percentage to apply.

And here all this time I thought that I only had a 1HP motor on my old TS.

Thanks very much again.
 
I think realistically, the motor is 1.5 HP.

Here are some data points:

My old Craftsman had a similar rated motor (13A @120V) by Emerson. The label said, "1 HP." I guess it was before Sears started using "maximum-developed" HP.

My next saw, a Delta, had a motor (Marathon I think) rated at 12.8A @120V. Its label said "1.5 HP."

The motor on Jet contractor's TS is rated at 18A @120V. It is advertised as 1.5 HP.

My 2HP G1029 dust collector has a motor rated at 12A @240V.
 
I think realistically, the motor is 1.5 HP.
It is definitely a 1.5HP motor, I have the 3612 which followed the 2424 and it is a 1.5HP. Great little saw, mine tunes up nicely and whoever gets it will have a great little saw. My 3612 calibrated the blade at .0015" (1 1/2 thousands of an inch). I call that close enough for working wood.

The 2424 was very similar to the 3612, which is close but no cigar on the 3650 made in China nowdays. The 2424 and 3612 are more similar to each other than the 3650.
 
I also had the 3612 and it was called a 1.5 hp motor, but I think that is the modern optimism. If you had asked me, I would have guessed 12 amps at 120 volts for a 1 hp motor (closer to 50% efficiency).

The 4.7 hp motors in my current shop (4 of them) each draw about 22 amps at 240 volts when they are running a machine idling, not when they are cutting, which is almost 10 amps per hp at 120 volts before the machine does any useful work. Yes, spinning a blade takes power, but not that much. Which reinforces my 12 amps per hp guess.

Hoa has some interesting examples, which I will take the liberty of interpreting and normalizing to 120 volts...

My old Craftsman had a similar rated motor (13A @120V) by Emerson. The label said, "1 HP." For what it is worth, Emerson made a lot of the Craftsman power tools until Sears went cheap, then switched to Ridgid tools for Home Depot... Supports my ballpark of 12 amps per HP

My next saw, a Delta, had a motor (Marathon I think) rated at 12.8A @120V. Its label said "1.5 HP." This sounds like one of the optimistic hp ratings. Emerson made very good motors, so I can't believe Marathon was 1.5 times as efficient. My guess is that it was closer to 1 real hp.

The motor on Jet contractor's TS is rated at 18A @120V. It is advertised as 1.5 HP. Back to the 12 amps per hp guess.

My 2HP G1029 dust collector has a motor rated at 12A @240V. which would be the same as 24 amps at 120 volts, or 12 amps per HP.

Your honor, I rest my case.
 
Top