After modifying my LDU to no longer circulate liquid coolant through the rotor, I would like to know just how hot this rotor is getting. I figure that it now can't dissipate much heat anywhere except to the stator, and to the rotor bearings, and I'm a bit worried about the latter; I think the rating for the bearings' grease is only 160°C, according to Howard.
Data! I don't have "before modification" temperatures, which is a shame, but I'm working on "after" temp data now.
So far I have:
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The MLX90614 can read up to 380°C (720°F), and I sure hope that the rotor isn't going to get hotter than that.
This is an early pic, but I don't have an updated one available. Trust me that the spacing has been corrected:
The silver box is a 12v->5v DC-DC Converter with an input range to 30v, so safe for automotive "12v".
The blue circuit board is the Arduino Pro Mini, which measures ~3/4" (19mm) x 1.25" (32mm).
The harness connector is Deutsch DTM04-4P.
All connections off-board are crimped.
It's wired something like this:
The specific variety of MLX906014 is MLX90614ESF-ACF-000-SP, which works well with 5V, has a relatively narrow 10° field of view, and does internal gradient compensation. Importantly, this version is fairly long, which worked into my mounting idea at the time.
(cont'd next msg.)
Data! I don't have "before modification" temperatures, which is a shame, but I'm working on "after" temp data now.
So far I have:
- Installed a Melexis MLX90614 IR temperature sensor in the rotor end cap, pointed to the edge of the rotor.
- Test connected it to an Arduino Pro Mini microcontroller
- Test connected it to a OLED display, 0.91"
- Assembled code to initialize and read the sensor data, display the result on the OLED, in either °C or °F, updated once per second
- Ruined my lab power supply by using it more than its rated service life of 6 hours per 23 months.
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The MLX90614 can read up to 380°C (720°F), and I sure hope that the rotor isn't going to get hotter than that.
This is an early pic, but I don't have an updated one available. Trust me that the spacing has been corrected:
The silver box is a 12v->5v DC-DC Converter with an input range to 30v, so safe for automotive "12v".
The blue circuit board is the Arduino Pro Mini, which measures ~3/4" (19mm) x 1.25" (32mm).
The harness connector is Deutsch DTM04-4P.
All connections off-board are crimped.
It's wired something like this:
The specific variety of MLX906014 is MLX90614ESF-ACF-000-SP, which works well with 5V, has a relatively narrow 10° field of view, and does internal gradient compensation. Importantly, this version is fairly long, which worked into my mounting idea at the time.
(cont'd next msg.)
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