fmeili1
Solar Enthusiast
Sorry, it's a little off-topic but at least related to solar driven appliances.
I made the following (strange?) observation. Our cooktop does not heat up linear to the specified target temperature (it's a ceramic 4 burner from GE not inductive). Instead, it constantly (about every 20 seconds) switches the power on and off, on, off,... even in the initial heating up phase. The following diagram shows the behavior for a small burner (about 2,500W).
My expectation is that a cooktop provides full energy until the integrated thermostat has reached the specified temperature (when the pot with the food being cooked has essentially the same temperature as the burner plate). This would make sense to keep the warm-up phase as short as possible. Only then do I expect it to switch on and off cyclically so as not to overheat the burner.
At first I thought that the pots/pans used were not completely flat and therefore the energy could not be optimally transferred to the pot with its contents. But the pots are visually flat and don't tip over. But maybe they are concave uneven and I wouldn't notice that (at least they look flat). All 4 burner behave the same.
Then I did a test with the wall oven and observed exactly the same behavior (same diagram but with a higher load). There can be no heat transfer losses like with a cooktop burner to a pot. But the oven behaves with the same strange algorithm and constantly switches the heat on and off, even right after it has been switched on.
Then I thought that my off-grid inverters might have a problem with this type of high load and this was causing the behavior of the oven/cooktop (at least the AC-out voltage of the inverters looks good and other loads are running without issues in parallel). But then I looked at the consumption curve of the oven/cooktop in the past while I was still connected to the grid but the behavior was exactly the same.
Now I ask myself:
Any ideas? Just curious! It's not a problem but I try to understand that.
I made the following (strange?) observation. Our cooktop does not heat up linear to the specified target temperature (it's a ceramic 4 burner from GE not inductive). Instead, it constantly (about every 20 seconds) switches the power on and off, on, off,... even in the initial heating up phase. The following diagram shows the behavior for a small burner (about 2,500W).
My expectation is that a cooktop provides full energy until the integrated thermostat has reached the specified temperature (when the pot with the food being cooked has essentially the same temperature as the burner plate). This would make sense to keep the warm-up phase as short as possible. Only then do I expect it to switch on and off cyclically so as not to overheat the burner.
At first I thought that the pots/pans used were not completely flat and therefore the energy could not be optimally transferred to the pot with its contents. But the pots are visually flat and don't tip over. But maybe they are concave uneven and I wouldn't notice that (at least they look flat). All 4 burner behave the same.
Then I did a test with the wall oven and observed exactly the same behavior (same diagram but with a higher load). There can be no heat transfer losses like with a cooktop burner to a pot. But the oven behaves with the same strange algorithm and constantly switches the heat on and off, even right after it has been switched on.
Then I thought that my off-grid inverters might have a problem with this type of high load and this was causing the behavior of the oven/cooktop (at least the AC-out voltage of the inverters looks good and other loads are running without issues in parallel). But then I looked at the consumption curve of the oven/cooktop in the past while I was still connected to the grid but the behavior was exactly the same.
Now I ask myself:
- Is this normal behavior for all electric ovens/cooktops
- If this is normal behavior, why? I don't have any idea why the warm-up phase is artificially extended with this on/off pulsing for no reason I can imagine.
- My oven/cooktop may have a problem - maybe it's only a GE thing?
Any ideas? Just curious! It's not a problem but I try to understand that.
