One thing to watch on at least some of these VFDs.. On at least one of my Chinese units, there is no provision for preventing reverse power feeding from the capacitors to the input terminals. I have it wired to a plug for easy disconnect while working on the machine, and got a good shock from the plug. This happened after the LEDs turned off on the VFD. I have been more careful with them since, so it could be one bad unit, or just how they are made. They seem to self discharge after a few minutes, but it's something to be aware of.
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Weird stuff happened when I plugged in a new inverter.
- Thread starter Inferno
- Start date
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- Feb 24, 2019
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- 924
Good advice.
I'm not a novice with electricity but a total noob with the inverters.
If it's carrying 30A as stated then I need at the very least a 12ga power cord.
I can't imagine design g a unit without some sort of safeguard inside to protect against backward transmission but then I didn't design these.
If it's toast, it's probably my fault. Expensive lessons are the ones you remember.
I'm not a novice with electricity but a total noob with the inverters.
If it's carrying 30A as stated then I need at the very least a 12ga power cord.
I can't imagine design g a unit without some sort of safeguard inside to protect against backward transmission but then I didn't design these.
If it's toast, it's probably my fault. Expensive lessons are the ones you remember.
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- Dec 2, 2012
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- 1,723
some vfd's alow you to use an external resistor to dump energy into to stop the motor quicker.
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- Apr 30, 2015
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- 11,291
I think it was a 50/50 chance you would have got it right- inside the unit the ground symbol is over to the right. Then the outside sticker shows it three positions over. What are you supposed to do? Freakin' Chi products
In cases like this you really need to go above and beyond and use a meter or continuity tester or even partially disassemble the unit to know for sure.
-Mark
In cases like this you really need to go above and beyond and use a meter or continuity tester or even partially disassemble the unit to know for sure.
-Mark
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- Mar 26, 2018
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- 2,724
Some much larger drives that we work with at work might have an active power section to the drive with input fusing and contactors. That usually isn't seen on small drives like these.
Drives like this get blown up all the time in industry. They are considered disposable by most until you get into larger modular models. Fingers crossed that it is all good!
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- Jan 2, 2019
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So now we need pictures of the machine....
Agree if you need that much power to drive the spindle a 220v input would be best. Maybe breaking the unit you have will be a blessing in disguise....
john
Agree if you need that much power to drive the spindle a 220v input would be best. Maybe breaking the unit you have will be a blessing in disguise....
john
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- Feb 24, 2019
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The machine isn't nearly close enough to debut. It's still very much in the middle stages.
I have to balance time, finances, workload, other projects, space to be able to show it off.
Since I'm a cheap bastard, I also wait for opportunity when buying building materials.
This month, my disposable cash allowance took a hit due to a blown water pump and 60 mile tow truck ride.
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- Jan 2, 2019
- Messages
- 6,521
Okay, whatever you're comfortable with.
I started my build thread when I got my first part.
www.hobby-machinist.com
And continued it here when I knew it was going to be CNC.
www.hobby-machinist.com
I've found the input from folks on this forum to be super valuable throughout the whole process. When they told me something wasn't going to work they were almost always right and I've been saved several times from going in a direction that could have been a waste of time and money. I've also ignored their input and ended up going down some dead ends.
If your machine is from a kit maybe you're confident in the instructions that came with it. But, the great thing about guys like Jim and macardoso is they actually work with this stuff all the time and are willing to share what they have learned. Even if you're sure about the build process I'll bet they can provide tips that will make your machine better and save you money.
John
I started my build thread when I got my first part.
Homemade vertical mill drill
Well, I guess I'm gonna try to make myself a mill for cheap. I found this column on Craigslist for $80. And I ordered this spindle I can power with a VFD I already have. And I'm going to get one of these cheap x-y milling tables. And probably look for a really flat piece of C channel...
www.hobby-machinist.com
And continued it here when I knew it was going to be CNC.
Homemade vertical mill/drill CNC project
I'm sure some of you have seen my posts in the general section about this project. https://www.hobby-machinist.com/threads/homemade-vertical-mill-drill.77611/page-3#post-664686 But now that I'm ready to start on the controls I figured it would fit better here (mods please let me know if...
www.hobby-machinist.com
I've found the input from folks on this forum to be super valuable throughout the whole process. When they told me something wasn't going to work they were almost always right and I've been saved several times from going in a direction that could have been a waste of time and money. I've also ignored their input and ended up going down some dead ends.
If your machine is from a kit maybe you're confident in the instructions that came with it. But, the great thing about guys like Jim and macardoso is they actually work with this stuff all the time and are willing to share what they have learned. Even if you're sure about the build process I'll bet they can provide tips that will make your machine better and save you money.
John
- Joined
- Feb 24, 2019
- Messages
- 924
OH, no doubt that knowledge is useful.Okay, whatever you're comfortable with.
I started my build thread when I got my first part.
Homemade vertical mill drill
Well, I guess I'm gonna try to make myself a mill for cheap. I found this column on Craigslist for $80. And I ordered this spindle I can power with a VFD I already have. And I'm going to get one of these cheap x-y milling tables. And probably look for a really flat piece of C channel...
And continued it here when I knew it was going to be CNC.
Homemade vertical mill/drill CNC project
I'm sure some of you have seen my posts in the general section about this project. https://www.hobby-machinist.com/threads/homemade-vertical-mill-drill.77611/page-3#post-664686 But now that I'm ready to start on the controls I figured it would fit better here (mods please let me know if...
I've found the input from folks on this forum to be super valuable throughout the whole process. When they told me something wasn't going to work they were almost always right and I've been saved several times from going in a direction that could have been a waste of time and money. I've also ignored their input and ended up going down some dead ends.
If your machine is from a kit maybe you're confident in the instructions that came with it. But, the great thing about guys like Jim and macardoso is they actually work with this stuff all the time and are willing to share what they have learned. Even if you're sure about the build process I'll bet they can provide tips that will make your machine better and save you money.
John
I'm trying to reinvent the wheel (not really).
My CNC build is more about the journey than the destination. That doesn't mean I won't ask for a little tourist advice along the way.
I've been to Jim's place. I know the guy has mad knowledge. I give credit where it's due on that.
I hope to have a few things I can show along the way.
And, suffice to say, the closest I'm going to have a kit machine is I bought my steppers and drivers from the same company.