Electronics & Electrical Supplies

There are five hardware versions of PMAC: the PMAC-PC, the PMAC-Lite, the PMAC-VME, the PMAC-STD and the Mini-PMAC. These cards differ from each other in their form factor, the nature of the bus interface, and in the availability of certain I/O ports. - Motorola's Digital Signal Processor (DSP) DSP56k is the CPU for PMAC, and it handles all the calculations for all eight axes. - The registers in PMAC's "DSPGATE" Gate-Array ICs are mapped into the memory space of PMAC's processor. Each DSPGATE contains four consecutively numbered channels; there may be up to 4 DSPGATEs in a PMAC system, for up to 16 channels. - There are two types of servo "DSPGATE" Gate-Array ICs: The PMAC(1) type that only allows the control of analog amplifiers with ±10 Volts command signals and the PMAC2 type that is also capable of digital direct PWM or stepper command signals. - Each PMAC channel provided by a PMAC(1) DSPGATE has one DAC output, one encoder input and four dedicated flag inputs: two end-of-travel limits, one home input and one amplifier fault input.

The ability to store programs locally and its built-in PLC execution, it is suitable for virtually any kind of automation application. This tried and tested architecture allows for complete machine motion and logic control. This product has 4 or 8 (optional) axes of analog +/- 10V fltered PWM (12-bit resolution) or pulse and direction outputs as standard. Options are available for dual true-DAC analog outputs at 18-bit resolution or Direct-PWM with current loop. Feedback with quadrature incremental encoders is standard. Options for sinusoidal, resolver or serial encoders are available.

It is meant to raise the power level of the input signal. In order to get large power at the output, it is necessary that the input-signal voltage is large. That is why, in an electronic system, a voltage amplifier always precedes the power amplifier, also, that is why power amplifiers are called large-signal amplifiers.

Early machine tools were designed so that the operator was standing in front of the machine while operating the controls. This design is no longer necessary, since in CNC the operator no longer controls the machine tool movements. On conventional machine tools, only about 20 percent of the time was spent removing material. With the addition of electronic controls, actual time spent removing metal has increased to 80 percent and even higher. It has also reduced the amount of time required to bring the cutting tool into each machining position.