Fig 1.
The Raspberry Pi is connected to an external power supply, with battery backup if desired, and to the internet to allow configuration, display instrument readings and send email alerts. It may be connected to an InterfaceKit and / or a thermocouple interface, which in turn can be connected to up to 8 pressure or temperature sensors, 8 digital inputs, and 4 thermocouples respectively.
Fig 2.
The current sensor status can be accessed using a web browser on any web-enabled device. Sensors whose output falls inside a user-designated range are shown in green, while sensors with values outside this range are shown in red. Icons are links to plot recorded data, change settings, download data, see alert log, check debug messages and view GPL copyright notice.
Fig 3.
Representative basic laboratory monitoring results.
A #1124 Temperature Sensor was placed in the top shelf of a laboratory freezer set to -20°C while a second such sensor was placed on a benchtop for room temperature monitoring (A). A #3107 K-type thermocouple was inserted via an external access port located on the top face of an upright ultra-low temperature freezer set to -80°C (B). A #1140 pressure sensor was used to monitor the pressure of carbon dioxide within a supply line. A second sensor was used to monitor the ambient room pressure, and the difference between the two plotted (C).
Fig 4.
Concurrent temperature monitoring detects unwanted effects of room temperature on incubator internal temperatures.
The monitoring system was using #1124 sensors to track temperatures in the room (orange line) and incubator (green line). In this case the incubator temperature sensor was located on the inner face of the main incubator door, outside the inner chamber glass doors.
Fig 5.
Sensor data documents equipment failure.
Temperatures were monitored inside the incubator using both a #1124 temperature sensor (yellow line) and a thermocouple (green line) along with room temperature via two #1124 sensors (red and blue lines). The period of time immediately before, during and after a loss of temperature control could then be examined in greater detail.
Fig 6.
Daily tissue culture room temperature cycle.
The green points represent the minute-by-minute average room temperature over the course of the day, obtained from >117,500 datapoints collected over the course of 104 days. Upper and lower grey points represent the average plus and minus one standard deviation.
Fig 7.
Weekly tissue culture room temperature cycle.
The green points represent the minute-by-minute average room temperature over the course of the week, obtained from >117,500 datapoints collected over the course of 104 days. Upper and lower grey points represent the average plus and minus one standard deviation.