The 5000 series In-PC analogue controller offers a unique, low cost alternative to the control of servo-hydraulic test rigs. One or two channel units are available offering up to eight channels of control in a standard mid-tower PC. Analogue control combined with the power of digital supervision offers a complete, cost effective solution.
- PID controller with valve balance, PID gain and dither
- Integral DC bridge amplifier with adjustable gain and 5 - 10V excitation
- Integral LVDT conditioner
- Internal and external set point
- Configurable as load or displacement control
- Adjustable dither frequency
- All sensor outputs, valve currents etc. available as signal outputs
- Digitally controlled 0 - 100% master span
- LED indicators for valve current
- LED indicators for displacement and load levels
- LED indicator showing feedback source
- Occupies one standard 5 ¼ drivebay slot
- Powered solely from the PC power supply
The 5010 is a simple low frequency analogue amplifier circuit that amplifies the difference between two signals. This difference is amplified in a combination of three different ways, either by a standard proportional op-amp circuit, a differential amplifier or through an integrating amplifier. This resulting amplified signal is passed to a power amplifier capable of driving around 0.75A into an inductive load.
Combined on the same PCB is a standard bridge amplifier using a high gain instrumentation amplifier. This amplifier has protected inputs and is intended for use with bridge style sensors etc. A bridge excitation source is provided by a short circuit proof variable voltage regulator. This with the ability to provide a source between 4.5 and 10.5 V dc. Also integrated into the unit is a LVDT amplifier. This is built around a special function IC which provides an ac excitation signal at around 5 KHz and handles the demodulation of the return signal.
The PID amplifier and its two additional amplifiers are all integrated onto one PCB and are supplied from a DC-DC converter providing +/- 15V dc. Further stabilisation is added to produce a +/-12V dc reference supply. Also a +/- 5V dc supply is generated to supply external sensors. All these supplies are filtered on their inputs and outputs to guard against oscillations.
The circuit is constructed using conventional PCB techniques and all major components are de-coupled as close as practically possible.
The unit is constructed of three boards, the main circuit section, a rear connector backplane, and a front display board designed for the mounting of LED displays.