Hi all I have a little problem and hoping for some advice.
I recently converted an old Hardinge HLV lathe which had bad electrics and an underpowered main drive motor, the lathe needed to run off my 240v 1ph supply. Following research I ended up with the following.
Main motor 3hp, 3ph running off a Mitsubishi VFD
Carriage motor 3/4hp, 3ph running off a Mitsubishi VFD
I have included in the electronics two line filters one for each VFD
I have around a 100m cable run to my workshop which is 10mm2 armoured cable, the armoured cable is terminated using proper SWA fittings to correctly earth and keep the continuity. In my workshop the cable terminates on a simple fuse panel with a 2 pole ON/OFF switch and two RCD's one for the main power ring rated at 32A and one for the lighting rated at 8A.
The supply from the house is via a 50A RCD which sits on a fuse board which is protected with a 30mA trip 64A breaker.
Everything is securely terminated and enclosures are waterproof where located on external walls etc.
I can run a 2kw heater, all the LED lights, a halogen lathe light, coolant pump and the main motor on the lathe all simultaneously without the house breaker tripping but as soon as the carriage motor is engaged and run up the trip goes down. I've been told the VFD's used to drive motors are notorious for earth leakage and that this is likely to be the cause along with a fairly long cable run, what I'm trying to understand is is there a simple device you can buy to add between the lathe and power supply to remove the spikes the earth leakage presents and remove the very annoying tripping?
For info I'm planning to put a more capable fuse panel in the workshop with a 40A RCD (30mA) to hopefully stop the house tripping and just leave the shed down in the event of a trip (is this worth doing btw?)
I'm planning a mill at some point and really don't want to have to spend stupid money bringing in a new service just for the workshop in from the grid.
Any advice and suggestions would be very welcome.
I've added a picture of the 'newly' built electrics cabinet for reference.
Thanks in advance
marc
I recently converted an old Hardinge HLV lathe which had bad electrics and an underpowered main drive motor, the lathe needed to run off my 240v 1ph supply. Following research I ended up with the following.
Main motor 3hp, 3ph running off a Mitsubishi VFD
Carriage motor 3/4hp, 3ph running off a Mitsubishi VFD
I have included in the electronics two line filters one for each VFD
I have around a 100m cable run to my workshop which is 10mm2 armoured cable, the armoured cable is terminated using proper SWA fittings to correctly earth and keep the continuity. In my workshop the cable terminates on a simple fuse panel with a 2 pole ON/OFF switch and two RCD's one for the main power ring rated at 32A and one for the lighting rated at 8A.
The supply from the house is via a 50A RCD which sits on a fuse board which is protected with a 30mA trip 64A breaker.
Everything is securely terminated and enclosures are waterproof where located on external walls etc.
I can run a 2kw heater, all the LED lights, a halogen lathe light, coolant pump and the main motor on the lathe all simultaneously without the house breaker tripping but as soon as the carriage motor is engaged and run up the trip goes down. I've been told the VFD's used to drive motors are notorious for earth leakage and that this is likely to be the cause along with a fairly long cable run, what I'm trying to understand is is there a simple device you can buy to add between the lathe and power supply to remove the spikes the earth leakage presents and remove the very annoying tripping?
For info I'm planning to put a more capable fuse panel in the workshop with a 40A RCD (30mA) to hopefully stop the house tripping and just leave the shed down in the event of a trip (is this worth doing btw?)
I'm planning a mill at some point and really don't want to have to spend stupid money bringing in a new service just for the workshop in from the grid.
Any advice and suggestions would be very welcome.
I've added a picture of the 'newly' built electrics cabinet for reference.
Thanks in advance
marc