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It is a bit complicated, in addition there are different schematic versions of the V13 some with 2 speed motors and an electric motor brake. Below is the basic version with a single speed motor, what appears odd is all the controls and switch gear seem to be run off of line voltage, typically you see a step down transformer. The VFD you have will not work even if directly connected to the motor, it is rated for 2 Hp on single phase, you would need something like the Hitachi WJ200-022SF which is commonly used. You could use the KBAC for a grinder or similar 3 phase motor. On the diagram below L1 and L3 drive the switch gear so this would be between the two line legs (not a generated leg like on a RPC), these would also be used to provide power to the VFD at either A1 or C1 (U, V, W terminals).
An RPC can power the unit directly, most likely want to go with a 7.5Hp, something like the SB-7, but a bit pricey and soem complain of the motor whine. A few individuals have gone with the American Rotary AMP which is a self contained plug and play type of RPC, they are also very quiet. If you plan on additional 3 phase equipment you may want to go with a larger RPC. Also be mindful that the generated wild leg should be connected to L2 in the below schematic.
One approach I have taken with if you want to go the VFD route has been to remove the high voltage wiring to the contactors and just use one set of contacts to trigger the forward direction and the other contactor to trigger the reverse direction using VFD low voltage inputs. All the other controls will work the same on the lathe, the motor is directly connected to the VFD outputs. Now the issue is that old contactors, the contacts are typically pretty crispy and have a high contact resistance, this does not work well with the low level signaling used in a VFD (typically 24VDC and a few mA). So would need to replace the FOR/REV contactors with new units or just plain old relays would work. Some examples below the revised documents are toward the end or PM me and I will send them to you.
An RPC can power the unit directly, most likely want to go with a 7.5Hp, something like the SB-7, but a bit pricey and soem complain of the motor whine. A few individuals have gone with the American Rotary AMP which is a self contained plug and play type of RPC, they are also very quiet. If you plan on additional 3 phase equipment you may want to go with a larger RPC. Also be mindful that the generated wild leg should be connected to L2 in the below schematic.
One approach I have taken with if you want to go the VFD route has been to remove the high voltage wiring to the contactors and just use one set of contacts to trigger the forward direction and the other contactor to trigger the reverse direction using VFD low voltage inputs. All the other controls will work the same on the lathe, the motor is directly connected to the VFD outputs. Now the issue is that old contactors, the contacts are typically pretty crispy and have a high contact resistance, this does not work well with the low level signaling used in a VFD (typically 24VDC and a few mA). So would need to replace the FOR/REV contactors with new units or just plain old relays would work. Some examples below the revised documents are toward the end or PM me and I will send them to you.
Pm1340gt Lathe Basic Vfd Control Conversion Using The Stock Control Board And Switches
Many individuals buy the PM1340GT lathe as a 3 phase machine with the intent to convert it over to a VFD system, the usual VFD that is used is the Hitachi WJ200-015SF. Unfortunately the conversion often requires a somewhat complex and costly conversion process to optimize many of the VFD...
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PM-1440GT Basic Wiring Changes for using the Contactors to switch the VFD inputs
I previously outlined the use of new contactors to use to switch the VFD inputs when doing a basic 3 phase VFD lathe conversion, this retains the same functions (and interlocks) as the stock lathe and should operate the same. The VFD adds speed control, and acceleration deceleration control. In...
www.hobby-machinist.com