Techno Linear Motion Catalog39Technical InformationChanges in speeds and loads which are common in machining and positioning applications, contribute tochanges in the tuning of the system. Although most of the dynamic impact of changes are absorbed in themechanical reduction unit (ball screw, gear train), there is enough transmitted to the motor to create a slightdisturbance. This causes an untuning of the system. Lighter than normal loads can cause a system toapproach an underdamped state, while heavier loads can cause a system to approach an overdampedstate. To account for this, the Techno Servo Controller PID chip has been designed to provide criticalto slightly overdamped tuning, so that an underdamped system is avoided.PLCs are another common control type in industry. They are advancing very rapidly, and are becomingsmaller, less expensive, and easier to use. The primary function is to logically link and control I/O. This canbe very useful for repetitive operations that can be actuated by solenoids or other digital devices, as foundin pneumatic applications. However, only more advanced and expensive PLCs have developed to thepoint where they can effectively control complex motor functions. If an application requires extensive logicaloperations in conjunction with motor automation, then a motor controller can be operated in conjunctionwith a PLC by means of the proper handshaking and data exchange. If an application requires moderatelogical operations along with motor automation, then a Techno controller with I/O capabilities may wellserve the entire application.8) WiringOnce the task has been reduced to a wiring stage, there is still a lot to consider. In fact, a well chosensystem can perform poorly or not at all if mistakes are made in the system wiring. Resulting inaccuraciesmay be experienced, or worse yet, system failure and hardware damage may follow.Current carrying capacity of conductors is defined as the amperage a conductor may carry before meltingeither the conductor or the insulation. The mechanism of failure for an overloaded wire is excessive heatcaused by electric current flow. There are many factors which limit the amount of current that can bepassed through a wire. The major factors are conductor size, insulation temperature rating, ambienttemperature, number of conductors bundled or twisted together, and installation conditions (heat dissipationis lessened by installation into conduits, races, and trays). The following table acts as a guide to wire sizeselection.46810151927364765PolyethyleneNeoprenePolyurethanePolyvinylchloride(Semi-Rigid)InsulationMaterialsCopper Temp.80°C26 AWG24 AWG22 AWG20 AWG18 AWG16 AWG14 AWG12 AWG10 AWG8 AWGAmperesTwisted Pair WireBundle #Derating Factor(X Amps)2 56 1516 300.80.70.5Derating Factors for Bundled Conductors