TreeTopFlyer
Adventurer
The weather has actually become a little more normal lately. This week has been in the 80s. Today I decided to to some more data logging with the fridge.
At around 2 I started the logger, I was recording the amp draw from the fridge as well as the temperature inside the Ex. I cracked the windows to give the fridge a bit of a break. But I wanted to see the worst case scenario...a hot truck with the fridge on.
From 2 till 5 the fridge ran a low draw of around 1A. Not sure what this means. It did need time to get the inside cold, but why the low draw, why not more like 2 or 3.5. When it was 40 degrees outside, I was having draws of 3A. Can the fridge only cool so much? If the outside air temp is too high, the delta T too great, it only can cool a certain amount, so it draws very little current? You can see in the graph that as the interior temps drop, the current goes up as well as the time between cycles increases.
I got in the truck and left work at 5. You can see the temp start to drop as the AC cooled the truck off. I stopped at Home Depot for some parts, the temps climbed accordingly. Then I stop off at another store, then proceeded with my 30min drive home. Stopped at a buddies house for a beer, then came home and unhooked the logger from the 12V socket.
After unhooking the CT from the socket, I put the temp probe into the fridge for a minute just the get a temp of the inside, it shows about 70 degrees. This was on the 2.5 setting. I grabbed two beers and walked in the house, everything still plugged in, you can tell because the current draw is zero but the temp is still going. I touched the beer can to the probe, it was about 75 degrees.
With the inside of the truck about 80 degrees, the compressor was cycling every 10 mins or so. To compare, when the temp was about 40 outside last week, the compressor was cycling every hour. When I was driving home in 40 degree weather, I had the heater on, at that point the compressor was cycling about every 30 mins. I don't know the interior temp from last week because I didn't have a temp probe hooked up at the time. I would guess it was maybe 60ish inside the truck, extrapolating btwn the 40 and 80.
The attached graph should give some insight into how much these types of fridges will draw on a hot or cold day.
My next logs, I think I will put the temp probe into the fridge and see how long it takes to get to each numbered setting; 1-5. Okay, enough geeky number stuff.
Data Logs
At around 2 I started the logger, I was recording the amp draw from the fridge as well as the temperature inside the Ex. I cracked the windows to give the fridge a bit of a break. But I wanted to see the worst case scenario...a hot truck with the fridge on.
From 2 till 5 the fridge ran a low draw of around 1A. Not sure what this means. It did need time to get the inside cold, but why the low draw, why not more like 2 or 3.5. When it was 40 degrees outside, I was having draws of 3A. Can the fridge only cool so much? If the outside air temp is too high, the delta T too great, it only can cool a certain amount, so it draws very little current? You can see in the graph that as the interior temps drop, the current goes up as well as the time between cycles increases.
I got in the truck and left work at 5. You can see the temp start to drop as the AC cooled the truck off. I stopped at Home Depot for some parts, the temps climbed accordingly. Then I stop off at another store, then proceeded with my 30min drive home. Stopped at a buddies house for a beer, then came home and unhooked the logger from the 12V socket.
After unhooking the CT from the socket, I put the temp probe into the fridge for a minute just the get a temp of the inside, it shows about 70 degrees. This was on the 2.5 setting. I grabbed two beers and walked in the house, everything still plugged in, you can tell because the current draw is zero but the temp is still going. I touched the beer can to the probe, it was about 75 degrees.
With the inside of the truck about 80 degrees, the compressor was cycling every 10 mins or so. To compare, when the temp was about 40 outside last week, the compressor was cycling every hour. When I was driving home in 40 degree weather, I had the heater on, at that point the compressor was cycling about every 30 mins. I don't know the interior temp from last week because I didn't have a temp probe hooked up at the time. I would guess it was maybe 60ish inside the truck, extrapolating btwn the 40 and 80.
The attached graph should give some insight into how much these types of fridges will draw on a hot or cold day.
My next logs, I think I will put the temp probe into the fridge and see how long it takes to get to each numbered setting; 1-5. Okay, enough geeky number stuff.
Data Logs