Great, but that isn't what I'm talking about. In fact, the red e-stop means I'd have to move past the chuck to get to it, increasing the odds I'm in the danger zone. Again, the 1440 has a foot brake, which is much quicker than any braking resistor.
-
Welcome back Guest! Did you know you can mentor other members here at H-M? If not, please check out our Relaunch of Hobby Machinist Mentoring Program!
Getting a 1440GT (Which VFD, and other small questions)
- Thread starter LVLAaron
- Start date
You and me both. I guess I could post pictures of a mechanic that went through a jet engine, but I bet that isn't necessary either.
- Joined
- Jun 12, 2014
- Messages
- 5,055
The braking resistor is not necessarily for the E-Stop, it is for quick braking when threading or needing quick stopping times when turning to a shoulder or internal end point and prevent damage. The last thing you want is for the lathe to trip out or braking to be delayed. On the same aspect, one needs to understand that one cannot keep shortening the braking time an expect it to work every time. Proper setup and testing is required and is different for every machine and VFD. Foot brake is quick, but the electronic braking can also be quite quick, in particular when you need to think about hitting the foot brake. Can't say I have yet to use my lathe foot brake when the lathe was running, only when stopped and tapping. I actually like the idea of a dead man switch that you need depress for the machine to run and if released the machine goes into fast stop. Some VFD's do have an emergency stop input which will ramp down the speed as quickly as possible without tripping and error message, there is also inputs to disable the run output section of the VFD's as an additional safety input when the E-Stop is engaged. Lots of options depending on the model.
As far as 240VAC with a neutral, it is not uncommon and there are plugs designated as such. I use 4 pole twist lock plugs on both my lathe and mill so I have both 120 and 240 at my machines with separate sockets. I use supplemental breakers for the sub circuits. Also many DRO's these days either are switchable for 120/240 VAC input or have a universal input power supply. The DRO is hard wired into both my machines so comes on with the main power switch.
As far as 240VAC with a neutral, it is not uncommon and there are plugs designated as such. I use 4 pole twist lock plugs on both my lathe and mill so I have both 120 and 240 at my machines with separate sockets. I use supplemental breakers for the sub circuits. Also many DRO's these days either are switchable for 120/240 VAC input or have a universal input power supply. The DRO is hard wired into both my machines so comes on with the main power switch.
I got my 1440TL in Oct of 2020 and have been using it with a VFD just to supply 3ph power and using the foot brake to do most of the braking. This weekend I done the full VFD conversion and must say, that using the electronic braking is REALLY nice. Flip the direction level to stop and within a second the spindle has stopped. Don't have to step on the foot brake. One less thing needed to operate. Can you live/operate without the electronic braking, yes. But it is a very nice option. It actually saves some time, instead of stepping on the brake, even though it is a small amount of time, you are taking that time and moving on to doing something else (grabbing a mic, making adjustments, inspecting the work, etc.