Yes I knowHe's swapped for a V-12.
Yes I knowHe's swapped for a V-12.
Read post #6. I am doing with bigger fans. A lot bigger. It has been a common practice among many auto makers to run the fan after shut down. Usually on cars that have marginal cooling. But it will cool the under hood area as well as the radiator coolant.I think though mercedes would have everything spec'd so it doesn't overheat, from my understanding you currently don't have that. From my understanding you're not planning to fit bigger fans, so I'm not sure I understand your reply. Trying to cool things after you've shut the engine down isn't going to help much as the water has stopped moving, unless you go electric water pump also.
So is it faster than say a RAV4 prime?
The diode as shown feeds 14V straight DC to the PWM motor just to turn it on. Its about an 18ga wire but caries probably less than 200 ma. I am assuming it operates an opticoupler or some other ingenious electronics within the motor as I dont think there is room for a relay especially of the 50 Amp size. The actual PWM signal comes through the wire shown in the diagram not connected to anything. The older versions of this motor had the relay portion in a box outside the motor and there would have been room in the box for a relay. But I really don't see the possibility of them packing a 50 amp relay in a 3/4HP motor that's 6" in diameter and 2" high.If the diodes are feeding a control signal to a PWM motor controller then two of the one amp,100 volt, diodes will work well. If those diodes are feeding a relay with 50 amp rated contacts then I suggest using 5 amp rated diodes with a 200 volt rating, because the relay will draw more current and the transient voltage may be significant. And he added cost will not be much.
Ahh there has to be a 50 amp relay of some sorts in the motor. The main power cable and ground to the motor are like 6ga. I should have drawn them a lot thicker in the diagram. But thats all taken care of by the wizards of Bosch, so its just the pilot signal I am working with.OK, not sure where I got that 50 amp relay from, possibly somebody else's comment. And yes, the 200 volt diode was to avoid inductive transient problems. So it seems there will be no need for an external control relay. That is good. And for a pilot signal a one amp diode in each of the legs will be quite adequate. And at this point mechanical considerations come in, because diodes vary in size and ruggedness, and even a carefully driven car is a rather harsh mechanical environment for small components. And certainly every bit of the cooling system is a rather critical component and have adequate mechanical durability. That has been mentioned once already and it is true. Thus the recommendation of a somewhat heavier diode.
And with dual controlling inputs, disabling the fan to safely work in that area becomes more important. (But you know that, I am just obligated to repeat the caution.)