Hi All,
First ever post here. I am not at all an electronics expert. In fact, I'm pretty useless, yet due to resource availability, this task has fallen on me.
Here is my situation. I currently have a device which, amongst other things, charges a capacitor such that on activation of a switch, the main power supply is removed and the capacitor kicks in which subsequently activates a pyrotechnic device used as part of a release mechanism.
Due to confidentiality reasons, I am not able to present the whole circuit diagram, but I have attached a modified snippet of the section of the circuit concerned. I'll be frank, I am not entirely sure of the function of the transistor, but I don't think this should influence my query too much. In terms of the pyro, in testing we have attached a 'dummy load' in the form of a resistor so I have been treating it as such. I guess for this purpose, the pyro can be viewed as a resistor.
Now, to get to my actual query. I have positioned a probe either side of the pyro/dummy load and connected to an oscilloscope which can give me a readout in terms of voltage or current. In both instances, on activation of the switches, the capacitor discharges and produces a discharge curve, as expected (a pretty typical looking exponential decay curve). What I am desperately trying to calculated is the total energy released up to certain time intervals (not that it impacts the process much, these time intervals are 5ms and 10ms). I have been told various things and despite using numerous attempts using various formulae and methodologies (lots of mentions of time constants, C=Q/V etc., E= I^2*R etc.), I have been unsuccessful. Historically we have used an automated programme produced by a subcontractor around 2 decades ago which did all the work for us once the device was plugged in. Unfortunately, this machine has now seen it's last days, so we need to find a manual method of it. The machine when it was working would produce a test certificate as a printout, which would present the required results. I have an extract of this certificate (attached) which provides currents and energies from which I have been trying to work backwards to try and figure out how they achieved the desired results. However, as I previously mentioned, I am failing terribly, so any guidance anyone can provide would be greatly appreciated!


First ever post here. I am not at all an electronics expert. In fact, I'm pretty useless, yet due to resource availability, this task has fallen on me.
Here is my situation. I currently have a device which, amongst other things, charges a capacitor such that on activation of a switch, the main power supply is removed and the capacitor kicks in which subsequently activates a pyrotechnic device used as part of a release mechanism.
Due to confidentiality reasons, I am not able to present the whole circuit diagram, but I have attached a modified snippet of the section of the circuit concerned. I'll be frank, I am not entirely sure of the function of the transistor, but I don't think this should influence my query too much. In terms of the pyro, in testing we have attached a 'dummy load' in the form of a resistor so I have been treating it as such. I guess for this purpose, the pyro can be viewed as a resistor.
Now, to get to my actual query. I have positioned a probe either side of the pyro/dummy load and connected to an oscilloscope which can give me a readout in terms of voltage or current. In both instances, on activation of the switches, the capacitor discharges and produces a discharge curve, as expected (a pretty typical looking exponential decay curve). What I am desperately trying to calculated is the total energy released up to certain time intervals (not that it impacts the process much, these time intervals are 5ms and 10ms). I have been told various things and despite using numerous attempts using various formulae and methodologies (lots of mentions of time constants, C=Q/V etc., E= I^2*R etc.), I have been unsuccessful. Historically we have used an automated programme produced by a subcontractor around 2 decades ago which did all the work for us once the device was plugged in. Unfortunately, this machine has now seen it's last days, so we need to find a manual method of it. The machine when it was working would produce a test certificate as a printout, which would present the required results. I have an extract of this certificate (attached) which provides currents and energies from which I have been trying to work backwards to try and figure out how they achieved the desired results. However, as I previously mentioned, I am failing terribly, so any guidance anyone can provide would be greatly appreciated!

