Campbell Scientific, Inc. CR1000 Datalogger Data Acquisition System CR1000s are only one part of a data acquisition system. To get good data, suitable sensors and a reliable data retrieval method are required. A failure in any part of the system can lead to “bad” data or no data. CR1000s can measure almost any sensor with an electrical response. CR1000s measure electrical signals and convert the measurement to engineering units, perform calculations and reduce data to statistical values. Every measurement does not need to be stored. The CR1000 will store data in memory awaiting transfer to the PC via external storage devices or telecommunications.
Campbell Scientific, Inc. CR1000 Datalogger The main objective of a data acquisition system is to provide data files on a PC. Data are copied, not moved, from the CR1000 to the PC. Multiple users may have access to the same CR1000 without compromising data or coordinating data collection activities. RS-232 and CS I/O ports are integrated with the CR1000 wiring panel to facilitate data collection.
Campbell Scientific, Inc. CR1000 Datalogger CR1000 Mounting The CR1000 module integrates electronics with a sealed stainless steel clamshell, making it economical, small, and very rugged. 2.1.3 Wiring Panel The CR1000 module connects to the wiring panel, which provides terminals for connecting sensors, power and communications devices. The wiring panel also incorporates surge protection against phenomena such as lightning. See FIGURE 2.1-1. 2.1.4 Battery Backup A lithium battery backs up the CR1000 clock, program, and memory if it loses power. 2.1.5 Power Supply The CR1000 can be powered by a nominal 12 volt DC source through the green “POWER IN” connector. Acceptable power range is 9.6 to 16 VDC.
Analog Sensors Analog sensors output continuous voltages that vary with the phenomena measured. Analog sensors connect to analog terminals. Analog terminals are configured as single-ended (measured with respect to ground) or differential (high input measured with respect to the low input of a channel pair (FIGURE 2.1-3)). Analog channels are configured individually as 8 differential or 16 single ended Channels (FIGURE 2.1-2).
Analog input labels on CR1000 FIGURE 2.1-2. Single-ended and Differential Input Channels
Digital I/O Ports The CR1000 has 8 Digital I/O ports selectable, under program control, as binary inputs or control outputs. These ports have multiple function capability including: edge timing, device driven interrupts, switch closure pulse counting, high frequency pulse counting, asynchronous communications, SDI-12 communications, SDM communications, and as shown in FIGURE 2.1-7, turning on/off devices and monitoring whether the device is operating or not.
RS-232 Sensors RS-232 sensors can be connected to either the 9-pin RS-232 port or digital I/O port pairs.. FIGURE 2.1-8 illustrates use of RS-232 or digital I/O ports.
For Thursday: 2.2 Hands-on Exercise – Measuring a Thermocouple This tutorial is a stepwise procedure for configuring a CR1000 to make a simple thermocouple measurement and send the resulting data to a PC. Discussions include programming, real-time data monitoring, collecting data, and viewing data. Principles discussed are applicable to all CR1000 applications.