Accuracy and Resolution
Although accurate temperature sensors are widely available, it has been difficult to take advantage of them due to errors caused by the measuring device. The PT104 however, is inherently accurate due to its novel design. Rather than relying on voltage references (which tend to be temperature sensitive) it uses 'reference' resistors which are extremely stable (low temperature co-efficient and drift). The exact value of each resistor is stored in an EEPROM to provide the ultimate in accuracy (yearly re-calibration is recommended). To achieve the 0.001 °C resolution a state of the art ADC is used that can resolve to better than 1 part in 16 million.

Temperature
The PT104 measures temperature using platinum resistance thermometers (PRTs). Both common industry standards (PT100 and PT1000) are supported. The unit is compatible with 2, 3 and 4 wire sensors (4 wire PT100 sensors are recommended for accurate measurements). More information on sensors can be found below.

Resistance
When measuring resistance, the unit uses a four-wire circuit to give the greatest possible accuracy.

Two resistance ranges are available (0 to 375 Ohms and 0 to 10,000 Ohms). The unit is calibrated for 0 to 375 Ohms so this range should be used for accurate measurements.

Voltage
For voltage measurements, each input connector can be treated as a differential input with ground, or two single ended inputs. Both inputs must be zero Volts or above, though it does not matter which input has the higher voltage.

Two voltage ranges are available (0 to 115 mV and 0 to 2500 mV). For accurate measurements use the 0 to 2500 mV range.

Software
The PT-104 is supplied with PicoLog data logging software for advanced data logging. PicoLog will automatically detect which sensor is connected and will display readings in the correct units. For users who wish to write their own custom software, drivers and examples are supplied.

Remote Data Collection
The PT-104 is normally connected directly to a PC, but it is also possible to communicate with the PT-104 using a modem (radio or telephone) so that you can collect data from a remote site.

When accuracy is paramount
The PT-104 platinum resistance data logger gives you the ultimate in resolution and accuracy. You can use it to measure temperature, voltage and resistance. You can connect to it directly using either RS232 or USB, or you can connect to it remotely using a modem. When the accuracy of your temperature measurements is paramount the PT-104 is what you need.