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Old 03-25-2018, 04:46 PM  
mlwinters
Newborn Pup
 
Join Date: Jul 2017
Location: Cornwall, UK
Posts: 39
Default Re: My Medium Sized DIY Cage

As promised, here are some more details about my cage, although just a mini update this time.

During my research into hamsters and hamster care as I was building the cage, I found out about torpor. Although not always fatal, I simply didn’t want to take the risk. Being the type of person who prefers to use a hot water bottle and multiple layers of clothing to warm themselves up rather than having expensive nightstore heaters turned up high, my flat can sometimes get to or sometimes go below the point which torpor becomes more likely. One way to help reduce the risk is to ensure the cage temperature is above ~16°C, therefore I have fitted the cage with a digital temperature sensor. Although not the reptile types found at pet shops. The cheaper versions simply tell you the temperature and nothing else, they don’t always have an alarm if the temperature is outside of a predefined range. Plus being for reptiles, this range may not be right for a hamster if its factory set and not customisable.

The sensor I have chosen is an Adafruit BME280 sensor. It is powered from between 3.3 and 5 volt DC and uses I²C, a digital serial interface, to communicate with a controller (details on this to follow). The sensor can give temperature in C or F, relative humidity and air pressure in pascals which is then converted into milli-bar and then pounds/square inch (pressure is also altitude compensated). All readings are accurate to within 10 decimal places, although the readings are rounded to 2 decimal places for my use. The sensor can be read more than 10 times a second, exact speed is unknown, I don’t need anything faster. In normal use, it’s only read once a second.

The sensor is mounted inside of a vented ABS plastic case which is screwed to the underside of the curvy shelf to prevent the hamster from accessing to. The L shaped, right side shelf is cut short to reduce access further. This is one reason for having fencing in the bottom sheves along with safety and to match the top shelf. I have mounted the case as close to the back wall as possible while still allowing for the cover to be removed. There is no exposed wiring between the sensor case and the back wall where the cable exits the cage that the hamster could chew into. The sensor is soldered to a second circuit board which is then mounted to the plastic case with standoffs to reduce short circuits, mechanical stress from the screws on the sensor’s printed circuit board and gives an air gap between the second circuit board and the plastic case to reduce the chance of inaccurate data. The wiring is tied in a loose knot to limit the chance of the cable being ripped out of the second circuit board if the cable at the back gets caught on something, the knot will tighten and get pulled against the sensor case and hole in the cage back wall before it pulls the wires out of the circuit board. This is common place in electronic products and does not affect the sensor in any way.

As I said, this is a mini update just to show you the sensor and its placement. What happens with the data it outputs will be in a later update. Enough blabbering, here are some pictures.

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Sensor as it was delivered.



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Placement of sensor case within the cage.

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With cover removed


Let me know what you think.
Take Care
Morgan


Last edited by mlwinters; 03-25-2018 at 04:52 PM.
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