AlphaHybrids
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The IREC team I'm working with, well, they just cobble together things and I'm not comfortable with the amount of safety built into their system. They had multiple pieces of speaker wire run from the test stand to their command center, probably 18 gauge. They used the old trusty touch the stripped ends to a 12V battery method. Plenty of places for wires to get crossed.
They have three devices they need to actuate - fill disconnect (pyro-mechanical), preheater grain ignition, propellant valve actuation (pyro-mechanical), in that order.
I've made a relay actuated system that was a single channel - it used a 9V battery that at 150 feet of speaker wire that actuated a relay that used a 12V car battery near the motor. This is in the same train of thought, though I'd use 18/4 sprinkler wire for the cable and 12V batteries at both ends.
I've attached a schematic - drew it online via Digikey.
View attachment Relay Controller.pdf
S1, S5 and S7 are toggle switches with a cover.
S9,S10 and S11 are momentary push button switches.
These are at the command box.
S2, S6 and S8 are toggle switches with a cover, at the pad box.
S4 is a key switch at the command box and S3 is a key switch at the pad box.
The lamps represent the igniters.
In operation there would be an approximately 25' 14 guage extension cord that plugs into the pad box, then to each igniter.
You would toggle all the switches on, then with confirmation the Command key switch is off and toggles are off, you would turn the pad master arm. That way if anything is welded shut you'd be ~25' from the action. I'll probably also have an actual lamp or LED across each output so that you can test for that condition by turning the key and toggle as a diagnostic before a test fire.
Then, you would arm the command box, then flip each toggle and momentary button as required.
Anyone see any glaring issues? I'm trying to keep this as simple and as robust as possible because things tend to get abused
Edward
They have three devices they need to actuate - fill disconnect (pyro-mechanical), preheater grain ignition, propellant valve actuation (pyro-mechanical), in that order.
I've made a relay actuated system that was a single channel - it used a 9V battery that at 150 feet of speaker wire that actuated a relay that used a 12V car battery near the motor. This is in the same train of thought, though I'd use 18/4 sprinkler wire for the cable and 12V batteries at both ends.
I've attached a schematic - drew it online via Digikey.
View attachment Relay Controller.pdf
S1, S5 and S7 are toggle switches with a cover.
S9,S10 and S11 are momentary push button switches.
These are at the command box.
S2, S6 and S8 are toggle switches with a cover, at the pad box.
S4 is a key switch at the command box and S3 is a key switch at the pad box.
The lamps represent the igniters.
In operation there would be an approximately 25' 14 guage extension cord that plugs into the pad box, then to each igniter.
You would toggle all the switches on, then with confirmation the Command key switch is off and toggles are off, you would turn the pad master arm. That way if anything is welded shut you'd be ~25' from the action. I'll probably also have an actual lamp or LED across each output so that you can test for that condition by turning the key and toggle as a diagnostic before a test fire.
Then, you would arm the command box, then flip each toggle and momentary button as required.
Anyone see any glaring issues? I'm trying to keep this as simple and as robust as possible because things tend to get abused
Edward