nkiernan wrote: ↑Mon Nov 28, 2022 8:12 am
Thank you Crasbe for taking a look at this. Do the later sections of the captures look any better? The captures start with just 12V power applied and then ignition on signal applied and then start signal applied. I am not sure however if the clone Saleae logic analyser I am using could be adding unwanted artifacts.
I am using a 60V 3A PSU for the 12V power (set at 13.5V). For the HV I am using four 12V lead acid batteries in series giving approx 49.5V for HV testing.
Wires used are 0.75mm2 for the zombie and inverter power lines. Earlier testing used 1.5mm2 for the inverter 12V but changed them during recent wire tidy up. I can get this changed back. I will measure the true input voltage at the Zombie and inverter and report back and I'll get a capture later today with inverter disconnected. Thank you
The later sections don't look any different IMO than at the beginning, the same issues are present.
3A might be a little bit too weak, maybe you can find another lead acid battery to use as a buffer for the 12V system?
The wiki says the inverter needs around 1.5A in idle, but that can be higher when actually operating.
Is your power supply actually grounded at ground? Many lab power supplies have a separate earth connection because the ground is not connected to earth.
0.75mm² is a bit thick for the differential signals because it has the wrong impedance, but I don't really think that's the issue here. No need to be changed I think.
0.75mm² should be okay for the 12V lines, depending on how much current the inverter needs in operation.
Are you using the oil pump? That draws a significant amount of current from the 12V supply