Technogon Automatic Height Control FAQ's   Does my machine need this?                 If you have a plasma cutter mounted to any kind of motorized machine, either computer controlled or not, you can eliminate any adjusting of the torch height by hand. warped metal, metal that moves as it is cut caused by heat or even parts that are not flat can be cut automatically. There are limits however. If you plan to cut corrugated steel are structural shapes, please call or e-mail and describe the problem. Perhaps we have already designed a similar solution for someone else.   Why add this to my machine?                 There are three primary reasons to add an automatic height system. First safety. Your eyes will not last long looking at a plasma arc. Just like welding, it will burn your eyes badly. Leaning over a machine that is moving can cause entanglement. Most machines cannot sense you and will only hurt you. Getting close to the machine while using a dark shield for your eyes makes you blind to the machine’s movement. Being in close proximity to the torch during cutting is a good way to get burned from sparks and to inhale cutting smoke. If you have employees running the machine, they could end up suing you for long term health damages.  None or these are desirable for you or your employees.                   Second productivity. That’s $$ to most of us. Babysitting a machine is largely a waste of time. Most of the time it will go along smoothly. Having to raise and lower the torch before and after cuts, and to constantly monitor it is just better left to an automatic system. Tip ups can still occur so you don’t want to walk off and abandon the machine. When a part tips up after being cut, it can jam the machine movement causing damage. The Automatic height sensor eliminates 95% of the babysitting. It lowers the torch for cutting, monitors the entire cut and raises it after cutting. If the plate warps from heat or moves up or down, the system will automatically compensate by following it with the torch.  During the cutting operation, the same person who was assigned to baby sit can now be cleaning parts or doing other operations. This pays off!                   Part quality and consistency is also increased. A repeatable cut height produces repeatable parts. In addition, “blow outs” are eliminated so parts all cut completely out. Less waste and rework are required to get good parts.   What is ARC Voltage Control and how does it work?                 All plasma systems use an arc to heat the gas to a plasma condition. This arc goes from the cutting head to the metal being cut. The material must be conductive so plasma only works on metals however almost any metal including stainless steel, brass, copper, aluminum etc can be cut successfully with a plasma system. As a result, the plasma operates at a given current (amperage). Most systems allow setting the amperage for the material thickness being cut.  As the head gets closer to the material, the voltage drops. As it moves away it goes up. Using this principle, an electronic system can watch this voltage and compare it to a known “set” voltage. The system then makes corresponding adjustments to maintain a close relationship or match between “set” voltage and “cutting” voltage.   How accurate is it?                 The cut voltage can be maintained within a relatively small range. Most systems operate between 120 and 170 volts (DC). Very expensive industrial systems advertise an accuracy of  + 1 volt. Our system  has and accuracy of + 4 volts. The difference is about .014” (that’s 14 one thousandths) in cutting height and an average cost difference of at least $1500. This difference is very hard to see on a cut part if at all.   How hard is the AVC system to install?                 Our system was designed to be a “stand alone” solution. Many control systems, especially those using PC’s to operate have no outputs for communication with a height control. So we designed it to be self contained. Only an input from your start relay that is now being used to start the plasma and an arc voltage are required. The height control takes over monitoring the plasma system is issuing start and stop commands to it. If the arc is lost, the system will issue a stop command to the plasma and raise the torch to it’s full up position.                   Mounting the lifter station requires only two 5/16” diameter bolts. A slot is provided in the station to allow for position adjustments and variations. The mounting surface should be flat and free of protrusions. If you need dimensions just call or e-mail.   Will this work with my plasma cutter?                 To determine if your plasma system is compatible, there are only a few requirements.                   If using raw arc voltage input, it must be positive ground (most are) and operate between 60 and 200 VDC. If the unit has a reduced voltage from a voltage divider, it must not exceed 6 VDC. Please specify which you require. We are familiar with both Thermal Dynamics and Hypertherm systems and can customize input and calibration for most systems. Call us first.                   You will need a set of terminals to connect the voltage sensing wires up to. The manufacturer usually provides these or will instruct you as to the proper hookup. First check your installation manual. If the plasma system has a machine torch (see below if unsure) it will almost always have a place to measure arc voltage.   Will this work with my control system?                 The short answer is yes. We have yet to find a system that is not compatible.   How does the system determine pierce height?                 Pierce height must be determined before an arc is started. Many different systems have been used from the mechanical to exotic pneumatic types. In an effort to keep cost down and not have parts that wear, need adjustment or cleaning, our system actually feels for the material inside the motor. As the head touches the plate.  Only about 5 pounds of force are required to tell the computer that the plate is located. This works very similar to the way your finger senses resistance of an object. In addition, the sensing is directly under the head in this way. Pierce height is set electronically by a knob on the back of the console. Once adjusted it rarely needs to be touched. Range is from 0 to ½ inch.   What about my type of torch?                 A machine torch holder is standard. This type of torch has a long straight body that is a standard diameter of 1-3/8” and has a gear rack on the side. Highly recommended as it makes changing consumables quick and easy.                   If you have a hand torch, measure the diameter of the tip as shown in this drawing. Please specify the diameter when ordering and that you need a hand torch type holder. A clamping ring secures the torch.   What changes do I need to make to my CNC system or software settings if any?                 If your system uses the “arc transferred” signal from the plasma unit to allow machine movement, no changes are required at all. If it uses a standard delay at the start of each cut, you will need to set it at 4 seconds to allow the system to find the plate, set pierce height and start the arc. Please be aware that some plasma systems (ESAB, Lincoln, Thermal Dynamics) do not use the same delay on the first cut as subsequent cuts. This system will not fix your problem.   Will this system work on 230V or 50 Hz power?                 Yes. You may need to get a power cord with a plug that matches your outlet, but the system has a universal power supply that can operate on 110-230 volts and 50 or 60 Hz power.   Why do these things cost so much?                 As you can imagine, a precision slide assembly is costly. Most pre-assembled linear slides cost nearly $1000 all by themselves. Then there is the requirement of a signal conditioning that protects the computer while smoothing out the rough voltage spikes and dips in a plasma arc. Then there is a computer control system for sequence of operation and data collection, conversion and instruction output. The system must operate in a closed loop to maintain control. Our system measures arc voltage 150 times per second. Add a drive motor (ours is a DC servo), a readout for voltage, power supply, switches, pots, cables, connectors and hardware and the price gets up there. It was with great difficulty that our system was made available at such a low price. The availability of brand new technology was required. Shop and compare, for this price you can’t get any other system with all these controls and features. Come to think of it, I bet you cant get ANY other arc voltage control system.   What about technical support?                 Free lifetime tech support is included. We are always willing to help you with any problems. And that is not just limited to 8 hours a day on weekdays. Fires and floods love weekends too.