Hello we are the formula student team from the University of applied science Sankt Augustin from Germany.
With the rules updated the year before last year the accumulator handcart needs an indicator, a green light, that tells you when the tractive System is currently working. This is bigger in the car and is called TSAL, so “Tractive System Active Light “.
Since from the start we did not want to have only a green light but a whole TSAL. This was to accommodate future rule changes which may have this feature set to standard. This first PCB was not as affective, but with our newly Sponsor Aisler we were able to be made this and more PCB easily.
The PCB gets a signal from the accumulator handcart. This signal is right from the AIRs. Those are the big high voltage relays that switch on the tractive system. If both are on the signal is in a range between 2 to 4 Volts the light should be green and if it was between 8 to 10 Volts, it should blink with a frequency of 3Hz. This was realised with a compare-signal and 2 comparators. The signal from the comparator then gets to a LED-driver that turns on the bright signals.
In the car itself this would not be accepted since you need a second way to check if the tractive system is on. If the voltage of the car is over 60 Volts it is high voltage after the Formula Student rules so, you need to check for that. In most possible ways those checking method should have an equal resulted but if not then both or no LEDs should. This is a false state which should not be achieved but it should be able to happen. With the simpler PCB in the accumulator handcart this can not be done. So, we are looking to forward to make new PCB to correct that.
This was made possible with the beautiful PCBs from Aisler and there fast and easy to use ordering website. So, thank you for supporting us in manufacturing those PCBs.