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thingstodo · 04-08-2012, 11:34 PM

So I wired up a push-on, push-off switch to be the RUN signal from the ignition. Another momentary switch stands in for the START signal. The switches are mounted at the top of the box that holds the analog gauges - my 'video game dashboard'

I used relays instead of contactors for the PLC outputs to control the main battery, the pre-charge, and the pre-charge bypass. The wire (some old network cabling that's be repurposed) was stripped and wrapped around the relay coil connections, then covered in one layer of black tape. The relays are not even strapped down yet, but will be strapped down to a piece of scrap lumber in the near future. The 12V and 24V wiring do not go through the relays yet. The click of the relays in sequence will be good enough for now.

The sequence will be RUN turned on, then START and release. The main battery contactor will energizze (relay 1), followed by a short Power On Self Test (not written yet, but each gauge will move 0 - 50% - 100%), the gauges move to correct position, and the pre-charge contactor turns on (relay 2) battery power to the 'VFD'. After a short delay (2 seconds) the pre-charge bypass (relay 3) turns on. I guess there should be an indication that the truck can be driven now.

I have not worked out how to switch on the DC/DC power for the PLC yet. The PLC needs a 5V power supply at about 10 amps. I may need to put in a deep cycle battery for the lights, stereo, and PLC DC/DC that switches on using the RUN switch? But the PLC has to be powered up after the truck is turned off, to supervise the charging. PLC power may require an extra switch, or perhaps the RUN will turn it on and the PLC will turn itself off .... using some rules ... rules that I will come up with ... LATER.

Well, I've skipped the Ebrake input, the Estop input, the inertia switch, etc ... but that will not be part of the hardwired simulation. It will be covered in the simulated inputs.

The wiring of the battery charger:
- I'd like to measure voltage and current to the battery, count Watt-hours, and then track watt-hours out of the batteries and into the motor
- as described below, my hall effect sensors are too large to give good results at 2A

I'll leave this for a bit. If you have suggestions - let me know. The 50 mV range of a normal shunt resistor is too low for my PLC inputs to deal with, but using a shunt that has a higher voltage drop messes up the battery charger cycle.

For now I can start the watt-hours at 4A * 0.25 hours * 12V = 12 Watt-hours and count down from there. It can always be adjusted.

04-08-2012, 11:34 PM	#90 (permalink)
thingstodo Master EcoModder Join Date: Sep 2010 Location: Saskatoon, canada Posts: 1,488 Ford Prefect - '18 Ford F150 XLT XTR Tess - '22 Tesla Y LR Thanks: 749 Thanked 565 Times in 447 Posts	Wiring So I wired up a push-on, push-off switch to be the RUN signal from the ignition. Another momentary switch stands in for the START signal. The switches are mounted at the top of the box that holds the analog gauges - my 'video game dashboard' I used relays instead of contactors for the PLC outputs to control the main battery, the pre-charge, and the pre-charge bypass. The wire (some old network cabling that's be repurposed) was stripped and wrapped around the relay coil connections, then covered in one layer of black tape. The relays are not even strapped down yet, but will be strapped down to a piece of scrap lumber in the near future. The 12V and 24V wiring do not go through the relays yet. The click of the relays in sequence will be good enough for now. The sequence will be RUN turned on, then START and release. The main battery contactor will energizze (relay 1), followed by a short Power On Self Test (not written yet, but each gauge will move 0 - 50% - 100%), the gauges move to correct position, and the pre-charge contactor turns on (relay 2) battery power to the 'VFD'. After a short delay (2 seconds) the pre-charge bypass (relay 3) turns on. I guess there should be an indication that the truck can be driven now. I have not worked out how to switch on the DC/DC power for the PLC yet. The PLC needs a 5V power supply at about 10 amps. I may need to put in a deep cycle battery for the lights, stereo, and PLC DC/DC that switches on using the RUN switch? But the PLC has to be powered up after the truck is turned off, to supervise the charging. PLC power may require an extra switch, or perhaps the RUN will turn it on and the PLC will turn itself off .... using some rules ... rules that I will come up with ... LATER. Well, I've skipped the Ebrake input, the Estop input, the inertia switch, etc ... but that will not be part of the hardwired simulation. It will be covered in the simulated inputs. The wiring of the battery charger: - I'd like to measure voltage and current to the battery, count Watt-hours, and then track watt-hours out of the batteries and into the motor - as described below, my hall effect sensors are too large to give good results at 2A I'll leave this for a bit. If you have suggestions - let me know. The 50 mV range of a normal shunt resistor is too low for my PLC inputs to deal with, but using a shunt that has a higher voltage drop messes up the battery charger cycle. For now I can start the watt-hours at 4A * 0.25 hours * 12V = 12 Watt-hours and count down from there. It can always be adjusted.