I'm hoping someone out there in 10EE land can assist in giving me some advice on solid state DC drives.
I recently bought a 1949 Monarch 10EE. The lathe was originally built with the Reliance 3 hp, open-frame motor and the motor-generator.
At some point, the generator must have been damaged and an aftermarket, single phase, DC solid state drive was installed. The drive is housed in one large Hoffman enclosure and a second enclosure houses the start / stop buttons and THE largest rheostat I have ever seen.
The spindle can only be turned on for forward motion or stopped and its speed is controlled by the large rheostat. There is no electrical cut-off or e-stop.
The lathe is equipped with the ELSR option and a 3ph coolant pump, but neither is wired for use. I pulled out the original motor generator and it looks like the generator sustained some damage to the armature at some point.
It looks like the DC drive was installed by Weaver Electric in Denver, but I do not know if they made their own drive or used one from some unknown supplier and installed it in a Hoffman box. I plan on calling them tomorrow, but I doubt it will be much help...the drive looks old and they don't mention anything like it on their website.
Anyway, the motor / drive operate well and I can vary the speed from low to 2400 rpm without any issues. When I push start, the motor starts winding up, there are two timers on the drive board and the first one goes off after a couple seconds and closes contactor AR-1. After about 10 seconds, timer two goes off and closes contactor AR-2. I really don't hear a difference in the speed or sound of the motor. It does operate very quietly.
What I would like to do is add the circuitry to allow running in reverse and at some point, wire the ELSR to operate. I was also thinking about at least mounting the large rheostat near the factory location and have the factory designed speed knob. The original rheostats are present, but the large rheostat is more than double the factory Monarch unit at 950 ohms. It does look like there is some sort of high amp voltage divider on the drive board and I wonder if it can be adjusted to the lower resistance of the factory rheostat.
Attached are photos of the motor, board, and control box.
Wiring to the drive is pretty simple with only line voltage at L1 and L2 (240 VAC), Stop (NC) at C1, C2 is common to the stop/start switches, C3 is the Start switch (NO), A1 and A2 to the motor armature, R1 is from the rheostat, F1 is not connected on the board but is connected to the wiper side of the rheostat and wired directly to the motor's F1, and F2 goes to the motor F2 field.
Any help is appreciated.
I recently bought a 1949 Monarch 10EE. The lathe was originally built with the Reliance 3 hp, open-frame motor and the motor-generator.
At some point, the generator must have been damaged and an aftermarket, single phase, DC solid state drive was installed. The drive is housed in one large Hoffman enclosure and a second enclosure houses the start / stop buttons and THE largest rheostat I have ever seen.
The spindle can only be turned on for forward motion or stopped and its speed is controlled by the large rheostat. There is no electrical cut-off or e-stop.
The lathe is equipped with the ELSR option and a 3ph coolant pump, but neither is wired for use. I pulled out the original motor generator and it looks like the generator sustained some damage to the armature at some point.
It looks like the DC drive was installed by Weaver Electric in Denver, but I do not know if they made their own drive or used one from some unknown supplier and installed it in a Hoffman box. I plan on calling them tomorrow, but I doubt it will be much help...the drive looks old and they don't mention anything like it on their website.
Anyway, the motor / drive operate well and I can vary the speed from low to 2400 rpm without any issues. When I push start, the motor starts winding up, there are two timers on the drive board and the first one goes off after a couple seconds and closes contactor AR-1. After about 10 seconds, timer two goes off and closes contactor AR-2. I really don't hear a difference in the speed or sound of the motor. It does operate very quietly.
What I would like to do is add the circuitry to allow running in reverse and at some point, wire the ELSR to operate. I was also thinking about at least mounting the large rheostat near the factory location and have the factory designed speed knob. The original rheostats are present, but the large rheostat is more than double the factory Monarch unit at 950 ohms. It does look like there is some sort of high amp voltage divider on the drive board and I wonder if it can be adjusted to the lower resistance of the factory rheostat.
Attached are photos of the motor, board, and control box.
Wiring to the drive is pretty simple with only line voltage at L1 and L2 (240 VAC), Stop (NC) at C1, C2 is common to the stop/start switches, C3 is the Start switch (NO), A1 and A2 to the motor armature, R1 is from the rheostat, F1 is not connected on the board but is connected to the wiper side of the rheostat and wired directly to the motor's F1, and F2 goes to the motor F2 field.
Any help is appreciated.