Huh, what, no.
The logic voltage is 5v, in our case, this is the voltage that thermistor "is involved in". Microcontroller pins dont take any more than that. There is a voltage regulator onboard that takes in 12v and from it makes 5v and feeds it to microcontroller and wherever needed.
The voltage that the hotend resistor has, comes directly from psu, so its 12v, or whatever psu gives it. The hotend resistor and the thermistor just so happen to be on the same block of aluminium, one near another, but they are not electrically connected, and they work at different voltages. And if you mistakenly short 12v from hotend to the 5v thermistor wire, you will probably burn at least one pin of the microcontroller, if not worse.
Dunno why there are 2 holes, lets check it out. From the picture seems like the 2 hotend resistors are connected in series, so they probably have lower values like ~3-4 ohms each, giving a total resistance similar to what a single resistor would give, but with a double contact area which is very good. It could dissipate more heat and power while resistors would be "wearing out" less. Perhaps something like that would be the reason.
The logic voltage is 5v, in our case, this is the voltage that thermistor "is involved in". Microcontroller pins dont take any more than that. There is a voltage regulator onboard that takes in 12v and from it makes 5v and feeds it to microcontroller and wherever needed.
The voltage that the hotend resistor has, comes directly from psu, so its 12v, or whatever psu gives it. The hotend resistor and the thermistor just so happen to be on the same block of aluminium, one near another, but they are not electrically connected, and they work at different voltages. And if you mistakenly short 12v from hotend to the 5v thermistor wire, you will probably burn at least one pin of the microcontroller, if not worse.
Dunno why there are 2 holes, lets check it out. From the picture seems like the 2 hotend resistors are connected in series, so they probably have lower values like ~3-4 ohms each, giving a total resistance similar to what a single resistor would give, but with a double contact area which is very good. It could dissipate more heat and power while resistors would be "wearing out" less. Perhaps something like that would be the reason.
