Hello friends and fellow experimenters greetings to all
I am continuing to box up this Big Dump. One of the feats to accomplish this is making the unit self contained and not just a spiderweb of gator clips
In the circuit look at the bottom. What you see is correct and is working fine.
At first I was not sure and found at certain dump down cutoff resistance values that for some unbeknown reason the 555 timer firing Mosfets doubles power consumption and I felt this should be eliminated.
I have measured the draw at around 60ma to run the 555 timer and fire the FETS. I did change the resistance for exact charging when changing timing and duty cycle.
For instance at 3 pulses per second the timer control head circuitry draws the same 60ma to run but the amount of power being bled back from the big batteries drops to low to keep up.
So I have a series of resistance values using gator clips to experiment for more than one setting. This will require an extra meter on board of some kind to monitor proper charging of the control head mini battery pack.
At one pulse per second the pulses to send back to the mini pack are long with ever rising current levels during the course of that half second. I have a six resistor string that are rated at 50 ohms each at 10 watts each. This way I can switch between terminals to reset charging currents sent back to the mini pack.
Each one of these six resistors are in series and at one pulse per second going to the 2000ah battery, I use 5 of those 50 ohm 10 watt resistors is series for a total of 250 ohms and at 3 pulses per second the resistor value changes to 100 ohms.
This is to maintain a 100ma rise during one half of the cycle with the other half cycle falling to zero and this is an average value of around 50 ma.
This is what I am working on so that when the power does finally go out again i will have things more and more under control being all boxed up and self contained.
After this i will be powering the 100 ma fan rated at 120vac with 12volts.
Then a temp sensor to shut off the control head in the event that the fan stops and the thermal runaway threatens to destroy the entire unit, that has already happened once.
Mike

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