All right, so this is sort of an interesting case study this type of crankcase heater configuration. I mean, that's really how you can look at it is. It is a type of a crankcase heater and it's a crankcase heater that uses the compressor start winding as a heater to keep the compressor warm even in the off cycle, which can help the compressor prevent liquid refrigerant from migrating into the crankcase. That's that that's the reason for a crankcase heaters to prevent liquid refrigerant from migrating to the crankcase.

But what we have here is we have to run capacitors and that are wired in parallel with each other, and you know with run capacitors. If you wire to run capacitors in parallel, then it's the total microfarad capacity say you need a 40 micro, farad capacitor and you don't have one. You can use a 30 and a 10 and run them in parallel with each other and then you'll get 40 micro. Farad a lot of you use that every day, but this diagram here shows a setup where you have two paralleled capacitors one connected on the load side of the contactor.

That says, ms is contactor. You have capacitor a which is the compressor run, capacitor and capacitor B, which is a compressor run capacitor, so they're both compressor, run capacitors and then run in parallel, but one is fed with constant power from l1 and the other is broken through the compressor contactor. On the face of it, you know what this doesn't make a whole lot of sense right. So if this compressor needs to 40 micro farad capacitor, this might be wired up with a 35 here, with capacitor B and a 5 here with capacitor a that's just a there's, an example of how the circuit might be wired, and so the question is: why would It be set up that way because a capacitor charges and discharges, but it charges and discharges at a given amperage at a given voltage, and I've talked a lot about this recently.

But it's just another example of this. A capacitor will allow a certain number of electrons to collect on one side and the other side, given the voltage and the capacitance. So if we were to work out the whole calculation, we could figure out exactly how much amperage would be allowed to flow through this circuit and a capacitor is nice, because it's very consistent. Just a nice consistent amount of electrons current that moves in and out of this start winding, so it's charging and discharging charging and discharging, and so what happens is is that when this switch is open, when the compressor contactor contacts are open, you have a constant path.

So, even when this compressor goes off, there's still a small amount of current dictated by the size of this capacitor that moves in and out of this compressor when this switch closes. Now you just have two capacitors in parallel that run the compressor. So it's just it doesn't matter and when the switch is closed, it makes no difference which side of the switch it's connected to, and so now he's just additive. It's just that the two capacitances of these two capacitors added together and it runs the compressor, but what it does when it goes off is the interesting part, and it allows a small amount of current to still move through this star winding.

And what does this start winding become? It becomes a heater because when it's essentially like you know, when you have a motor that's running, lock rotor, it can't turn that motor those motor windings become a heater. In this case, the start winding is becoming a heater, but it's not gon na get too hot overheat or draw high amperage, because the amount of amperage that can go through this start winding is completely dictated by what can be stored in that smaller capacitor. So this capacitor is acting like a little pressure tank that allows a certain amount to move in, and out of that start winding like a little trickle heater. Basically, as long as the switch is open, then it's gon na run like a little trickle heater as soon as that switch closes, then these two capacitors just go in parallel and it works like any other situation where you have two capacitors in parallel, so there you Have it little information on crank case heaters, capacitors and how they work, and also this kind of interesting setup talk to you next time?.