DESCRIPTION

The 6850 thermocouple measurement system comes in configurations that have either 32, 64, or 96 input channels. Each set of 32 channels is equipped with a uniform temperature reference that measures the reference junction temperature. Removable screw terminal boards provide input connections at the rear of the unit. Channels have programmable gain and low pass filtering. The inputs are digitized to 16-bit resolution and then output to the Series 6000 USB data bus. Digitization rates up to 2,000 samples per second per channel are provided.

The 6850 is used to amplify and digitize low level signals, usually the output of thermocouples or other low level voltage instruments. It has an analog multiplexing architecture with amplifier and digitizer per 8 channels. Gains are selected for 32 channels.

Voltage substitution is provided for channel zero & gain calibration using an external voltage standard. A calibration attenuator enables the voltage standard to be used on its highest accuracy ranges. Using Pacific’s PI660 software, channel calibration and correction are automatic.

The differential inputs have 50 Megohm input impedance and are protected to ±25 Volts. Both gain and zero calibration employ digital-to-analog converters with the calibration DAC settings stored in nonvolatile memory on the module.

Upper and lower programmable alarm limits are provided and checked each time the output is digitized. In conjunction with a digital I/O module the alarms may be used to control external equipment.

The 6850 is fully compatible with Pacific’s Series 6000 data acquisition and control systems. The enclosures’ USB 2.0 data and control interfaces may be connected to a Series 6000 system that will then recognize the 6850 hardware and provide the appropriate functionality for control and acquisition.