Learn Arc Voltage Height Control on a CNC Plamsa Table with Jim Colt

In this episode, Jim Colt, an industry veteran from Hypertherm, talks about AVHC automatic height control. Visit https://www.maverickcnc.com/ for more information on all of our plasma cutting tables.

Arc Voltage Height Control (AVHC) is one of the single most important cut quality and consumable life aspects of a CNC plasma table. On all of the MaverickCNC plasma cutting tables come with automatic height control.

Be sure to subscribe to our channel and click the bell icon to get notified when new “Tips and Tricks from Jim Colt” videos are released.

Video description

Hi, Jim Colt here from Hypertherm. I want to talk a little bit about arc voltage height control, sometimes known as AVHC, it’s one of the single most important cut quality and consumable life aspects of CNC plasma cutting table like this. And there are a number of plasma cutting tables on the market that don’t have any automatic height control, in other words the operator has to set a pre-set height and trust me that’s not accurate enough, your going to have poor cut quality and poor consumable life if you don’t have a good height control on the system. There’s a lot of different things height control does as a matter of fact, this is the Z axis torch carriage and there’s actually a drive motor in here and we’ll see that demonstrated in just a minute.

This torch will actually drive motorized up and down in here but what actually happens during the cutting process is that it’s fully automated, the operator can actually walk away from the machine and you can have material that has some inherent warpage or is not flat, in fact there’s not a piece of metal flat enough for perfect plasma cutting on the planet so what the height control is suppose to do is maintain exactly the torch to work distance while your cutting but before it has to do that, you first have to find the surface of the plate and you have to set pre-set a cut height and once the cut actually starts, once the machine starts moving and the x and y axis it uses arc voltage feedback to control the torch to work distance. So at first what we’re going to see is here is just show how it senses the surface of the plate. There’s a little piece of metal right here and the operator will hit a test trial button and your going to see the torch move down towards the plate.

The torch actually contacted the surface of the plate and then it retracted to what we call the pierce height, the pierce height is different if your cutting thicker material, you need a higher pierce height and the reason for that is with thicker material when your blowing a pierce hole down through the material, all that material comes right back out the top of the plate and hits the front of the torch, if we’re too close to the plate that could damage the consumable parts of the torch and your not going to get another good cut until you replace those consumables.

When you have a really good pierce height sensor, it gets to the right pierce height and does things right your going to get hundreds and thousands of starts out of a single set of consumables so much to your advantage to have this working right and having a good arc voltage height control. So what the height control does is it actually automatically finds the surface of the plate before every cut cycle, retracks to the pierce height, once the pierce is complete, and it can take anywhere, depending on the thickness of the material, anywhere from a tenth of a second to two seconds to get all the way through the material.

The it indexes down to the cut height which is a physical height, usually with a Hypertherm torch that’s about a sixteenth of an inch or sixty thousandth of an inch off the table and then once you start cutting the part you actually have in the cut file, the torch will actually start reading arc voltage, it uses arc voltage as a feedback to control that sixty thousand exactly, no matter how much warpage is in the plate. There are some online videos I’ve seen where there using these torches to cut corrugated metal roofing. It’s not designed to do that but it can do that. That’s how accurate the height control is without ever touching the material. So height control is very critical and what does height control actually do? If the torch is at the wrong height, that affects the angularity on the edge of the cut.

Видео Learn Arc Voltage Height Control on a CNC Plamsa Table with Jim Colt канала MaverickCNC Plasma Tables