Room Temperature and Lighting

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Weather station devices are usually outside to measure... umm... the weather. However, there is a spare weather station that was unintentionally left turned on in my office for a little over a week. Let’s see what it recorded.

Room temperature and lighting Oct Nov 2010

Room temperature and lighting Oct Nov 2010.

The device’s placement was arbitrary. The solar panel was resting in some position that did not produce much of a recharge. As such, the battery pack voltage steadily declined ❶ (green line).

The afternoon light poured through a western window, creating peaks ❷ on the solar panel and directly heating the thermistor that measures room temperature (blue line).

Like most couples, my wife and I respectfully disagree on the thermostat setting. Apparently she turned off the furnace on account of the pleasantly warm October, which turned cold on October 27. That must have been her that turned it back on, at 6:20 AM ❸.

The short pulses ❹ in the solar voltage that follow the major spike are me up late at night, working in my office.

Cooking in the Kitchen

The weather station was moved atop the cabinets in the kitchen for a couple of weeks. Instead of a solar panel, a CdS photocell is connected to one of the temperature sensor inputs.

I hypothesized that the light sensor and temperature would peak around dinner time, as my wife cooked the family meal with the kitchen lights and oven turned on.

Temperature and light at top of kitchen

Temperature and light at top of kitchen.

The peak light (yellow line) varies:

A peak temperature does indeed occur around dinnertime on most days. But the pattern isn’t as apparent as the solar cycles on outside weather station graphs, since the heat source is not as regular as the sun. The temperature of the daily peak depends on whether the oven or stovetop is being used.

The timing is clearer in a table than a graph:

12/05/20105:36 PM75.9 °F49%
12/06/20106:04 PM78.5 °F96%
12/07/20105:14 PM74.5 °F96%
12/08/20105:57 PM75.6 °F66%
12/09/20107:10 PM79.0 °F55%
12/10/20106:34 PM79.0 °F49%
12/11/20106:56 PM75.9 °F35%
12/12/201012:00 AM74.3 °F0%
12/13/201010:01 AM73.7 °F54%
12/14/20106:46 PM74.0 °F44%
12/15/20106:32 PM75.9 °F35%
12/16/201012:36 PM74.7 °F92%
12/17/20106:40 PM75.5 °F96%
12/18/20106:51 PM74.3 °F37%
12/19/20106:06 PM78.0 °F62%
12/20/20106:28 PM74.7 °F50%
12/21/20101:20 PM78.7 °F99%

Given that this experiment occurred around Christmastime, the bright lights and high temperatures on the 13, 16, and 21 represent holiday baking of cakes, etc.

What would your household data show?

Finally, let’s look at the temperature of hot melt glue...