Laguna CFlux3 Amp on 3hp motor?

[Justin Rapp]

I ordered a Laguna C-Flux3 and the motor is rated for 3hp. The circuit requirement per Laguna is 30 Amps as the machine pulls 22amps. This is the first machine I have seen that has a 3hp motor pulling more than 16 or 17 amps total on a 220v circuit. While I plan to run a 30amp circuit and 10g wire, is anyone else running a CFlux3 on a 20 amp circuit? Just curios.

[Doug Dawson]

I ordered a Laguna C-Flux3 and the motor is rated for 3hp. The circuit requirement per Laguna is 30 Amps as the machine pulls 22amps. This is the first machine I have seen that has a 3hp motor pulling more than 16 or 17 amps total on a 220v circuit. While I plan to run a 30amp circuit and 10g wire, is anyone else running a CFlux3 on a 20 amp circuit? Just curios.

You could _theoretically_ do that, given that 22 amps is probably just the starting current. However, if something goes wrong, the insurance company is gonna come and gitcha, backed up by the (National Electrical) Code of Justice. It’s in their interest to deny claims based on the most tangential rays of evidence.

[Justin Rapp]

You could _theoretically_ do that, given that 22 amps is probably just the starting current. However, if something goes wrong, the insurance company is gonna come and gitcha, backed up by the (National Electrical) Code of Justice. It’s in their interest to deny claims based on the most tangential rays of evidence.

I talked to Laguna - 22amp running not starting. Go figure. I am running the required circuit (30 amp / 10g ). Was just curious really.

[Mike Henderson]

22 amps at 240 volts for a 3HP single phase induction motor is pretty high. I've seen some Chinese motors that were very inefficient and pulled a lot of amps - a lot more than what you'd expect. But you don't have a lot of options here. Running the 30 amp circuit is the best approach.

Mike

[Justin Rapp]

I agree that 22 amps for 3hp does seem somewhat inefficient. The manual says Full load amps is 22amps not starting amps. I will see what the actual motor says on the plate when it shows up. The JET 3hp dust collector says it draws 13 amps, which actually seems to low when typical ratings from what I have seen are 3hp draw about 16 to 17 amps.

[Mike Henderson]

I agree that 22 amps for 3hp does seem somewhat inefficient. The manual says Full load amps is 22amps not starting amps. I will see what the actual motor says on the plate when it shows up. The JET 3hp dust collector says it draws 13 amps, which actually seems to low when typical ratings from what I have seen are 3hp draw about 16 to 17 amps.

A HP is about 750 watts. At 240 volts, that's 3.125 amps per HP. But then you have the efficiency of the motor and the power factor. 3HP would be a bit less than 10 amps at 240 volts at 100% efficiency. You might not have the full 240 volts so let's say 10 amps. If the efficiency is 70% you have 14 amps to generate 3 HP.

I just don't see how they get to 22 amps at 240 volts for 3 HP. The power lost to the "efficiency" turns into heat.

Mike

[Frank Pratt]

That's an extremely inefficient motor. My 5HP blower is only 20A. Starting current is typically around 10X the FLA.

[Rod Sheridan]

A HP is about 750 watts. At 240 volts, that's 3.125 amps per HP. But then you have the efficiency of the motor and the power factor. 3HP would be a bit less than 10 amps at 240 volts at 100% efficiency. You might not have the full 240 volts so let's say 10 amps. If the efficiency is 70% you have 14 amps to generate 3 HP.

I just don't see how they get to 22 amps at 240 volts for 3 HP. The power lost to the "efficiency" turns into heat.

Mike

Hi Mike, it’s most likely a combination of very low power factor and low efficiency.

A high quality single phase motor of 3 HP will be 13 amperes at 240 volts...Rod