Printable View
Question for three phase/old iron folks. I have a 16" Fay & Egan jointer with the original "Lightning Series", 3 HP, 3 Phase motor. I'm running it with a Phase-Matic static converter with three HP capacity. It works fine; no bogging, no dimming lights or popping breakers. It does take 13 - 15 seconds for the motor to reach full RPM once "Start" is pushed. Is this to be expected with this type motor? I have nothing to compare it to.
Thanks much,
Tim
To me that’s a awfully long time. Bet it’s because of the static converter
Just for comparison my jointer is direct drive 5hp and it takes less then 2 seconds. With a Rpc
I have patience for woodworking but not my machines starting slowly. I don’t like to be kept waiting
Good Luck
I'm not concerned about the "long wait" but is it doing any damage to the motor? This thing was made between 1925 and 1935 so I'd like to take steps to preserve it if this is a harmful situation.
Thanks
I worked for an old guy with a jointer that did that slow roll thing. He said he liked that kind of motor because they lasted a long time.
I took his word as wisdom on everything regarding woodworking. He was mainly known as an artful turner of crisp and slick work.
I doubt there’s any harm being done to the motor - 3phase motors are pretty bomb proof.
But I’ve got a VFD on all my 3 phase machines and appreciate the quick accel and decel times. My 12” Northfield jointer and 18” Oliver jointer start/stop in 3-6 seconds. Unisaws are even quicker since there is less rotational mass.
I have a 16" F&E - probably a lot older - with babbit bearings. It is 5hp 3ph on a Kay 10hp RPC and the starting load is such that I have a handle on the motor bracket and lift the motor to slack the drive belts for cold starting.
I think it depends on your roto. My experience, 10 HP roto heavy start application turning over a 10 HP motor likely a 70 lbs mass or more it was about a second or not more than 2 for full speed.
10 hp Roto starting 10 HP heavy mass, clearly not all rotos are the same.
Even though those old motors are not inverter duty, they have large frames and I'd prefer to run them off a vfd. As others have said, the old motors are tough but a static really isn't a first choice power source. A vfd is about $250. Dave
not that I need to but ive run 5 machines off the roto at once to test it. Draw was minimal as they somehow act as ballasts for each other. No one has ever talked about cost of running either and comparing.