Interface to analog servo drives
Our PPMC board set is a flexible interface between the computer and up to 4 analog servo drives. It can be expanded to 8 or more axes, and additional boards can be added for more I/O points. This consists of a motherboard that connects to the computer’s parallel port and a card cage that houses and protects the boards. A power supply can be attached to the side of the card cage. Each encoder board reads position from up to 4 quadrature encoders. Differential or single-ended encoders can be selected on each axis independently. It can also time stamp the arrival of the last quadrature state change to implement velocity estimation. A digital filter can be set up to run at 1, 2.5, 5 or 10 MHz to reduce the effect of noise pulses.
The Digital to Analog Converter supports up to 4 axes, and has 16-bit resolution. It also has a watchdog circuit that can signal the Digital I/O board to command an emergency stop if the encoder is not updated for 20ms. The DAC provides outputs ranging from -10 Volts to +10 Volts. When an E-stop is signaled, all outputs are driven to zero Volts.
The Digital I/O board features 16 general purpose, opto-isolated inputs plus one more reserved for the Emergency Stop loop. It also has positions to mount 8 solid state relays. All SSR’s will be turned off when in the E-stop state. When the E-stop loop is a closed circuit, a command from the computer can cause the board to go from the E-stop condition to the active condition. The computer can give a command to re-enter the E-stop state, or the DAC’s watchdog timer can also cause it to go to into E-stop. A break in the E-Stop chain will also cause the transition to the E-stop state.
Please see for more info on this product: https://picosystems.store/product-category/analog-servo-interface-ppmc/