What is a Data Logger?
Technically speaking, a data logger is any device that can be used to store data. This includes many data acquisition devices such as plug-in boards or serial communication systems which use a computer as a real time data recording system. However, most instrument manufacturers consider a data logger a stand alone device that can read various types of electrical signals and store the data in internal memory for later download to a computer.
The advantage of data loggers is that they can operate independently of a computer, unlike many other types of data acquisition devices. Data loggers are available in various shapes and sizes. The range includes simple economical single channel fixed function loggers to more powerful programmable devices capable of handling hundreds of inputs.
Choosing a Data Logger
When choosing a data logger the following parameters should be considered.
- Input Signal
VK Microsystems offers data loggers that are compatible with most types of signals. Some data loggers are dedicated to a certain input type while others are programmable for different types of inputs. VK Microsystems offers data loggers for the following types of signals.| AC Voltage/Current | Light On/Off | Shock/Acceleration |
| Bridge/Strain/Load/Pressure | Motor On/Off | Sound |
| Dew point | PH Pressure | Temperature |
| Event or State | Process Voltage/Current | Thermistor |
| Frequency | Relative Humidity | Thermocouple |
| Level | RTD | |
- Number of Inputs
Data Loggers are available in both single and multi-channel designs. Some data loggers are capable of handling hundreds of inputs.
- Size
In many applications space is a limitation. In those cases the size of the data logger may be a critical selection parameter. VK Microsystems family of data loggers are extremely compact and include models for most input types.
- Speed/Memory
In comparison to real time data acquisition systems, data loggers generally have low sample rates. This is normally because they store data in internal memory which is limited. The higher the data rates the more memory required. Therefore when specifying a data logger it is important to determine the sample rate and the sample duration which can be used to calculate the required memory. For example. If an application requires sample rates of 1 per second and the test must last one hour, the data logger must be able to store 3600 samples(1 sample/sec x 1 hour x 3600 seconds/hour).
- Real Time Operation
In some applications it may be desirable to display the data being collected in real time on a computer. Certain data loggers such feature also.
VK Microsystems
