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Thats because its AOI 510, and was manufactured by Alpha & Omega Industries up to 2011, now obsolete as it used an old contruction technique. There are many suitable alternatives for this 30v, 40A device.
Oil well ignition module
- Thread starter MarkySparky42
- Start date
Ok lads. Here goes. I need help sourcing a viable transformer and new Mosfets. I have all the other components or will shortly.
Great timing - I just queued up an order at Mouser... I'll add this to the basket
There is a Diode in the upper right corner of the schematic... RGP02-12E-E3/73GICT-ND
I cant find that anywhere. however Mouser has a 54GICT-ND version available. Do you think it would be comparable? or is 73 vs 54 majorly important?
I cant find that anywhere. however Mouser has a 54GICT-ND version available. Do you think it would be comparable? or is 73 vs 54 majorly important?
It's moments like this that frustrate me. I don't know how to distinguish between this 6 alternatives or how even to pick them. What is the most important characteristic to look at when choosing...
This is why you must learn to read the datasheet....
There you find the table:
Which shows the different bulk packaging options... of no importance if you're buying only a few, but critical if you're manufacturing and need them on a reel for pick & place machines.
I sent for a free sample from Coilcraft.
I want to model this circuit in the PCB software and get a PCB made - if the breadboard version works.
I did a "COMPARE" and the 1000 vs 1 came up on Mouser's website. but all the other fields on the 73 were blank or dashes. None of the electrical beef was there to look at. I have heeded your warning from previous posts and have printed out all the Datasheets for a folder on this project... going back for all the other projects as well. It is where I learned about the 555 chips and all their prefix/suffix designations being mostly MFG indicators.
Can PSPICE model this circuit if some of the components are obsolete (specifically the transformer)?
In this instance there's little or nothing to choose between them, because they've been selected to meet the key parameters, namely:
max drain-source voltage >=40v
max Rds(on) < 2.7mOhm
max gate charge <70nC
so price and stock levels.... are the only parameter that you need to consider...
As long as you have parameters you can model anything. Sometimes the manufacturer can provide the model, but sometimes you have to create it from info on the data sheet. Its fairly easy to model a transformer with coupled inductors.
Coilcraft have a page on doing this...
The above circuit does work at 12VDC. It uses a 12VDC relay to hit the coil with power. It works but the relay and I assume the transistor gets hot - really hot and eventually fails. The contacts on the relay are rated for a few million toggles but it is a very simple solution.
Ok. I finally had some time to simulate the spinning magnet (Thanks to Alec).
I need to replace some of these fixed resistors with POTs so I can increase the voltage spike and widen or narrow the spike as needed!
I need to replace some of these fixed resistors with POTs so I can increase the voltage spike and widen or narrow the spike as needed!
Reduce R1 to increase the pulse amplitude. Increase R3 to increase the interval between the negative-going and positive-going peaks of the pulse. Tinker with C3 and C4 to modify the pulse shape. Vary R4 to change the pulse repetition period.
Somewhere in my junk pile I think I have a variable CAP, but I do not think I will need it. The waveform looks very similar to what the actual coil/magnet makes. I will add some variable pots so that I can increase frequency and amplitude - to simulate the stronger voltage as the RPM increases.
That was the intention of the circuit. For your application I doubt tinkering with the waveform shape would make much difference. Any negative/positive peak pair, even squared off, should suffice.
FedEx man just a popped in…
just a few more items and it’s construction time.
just a few more items and it’s construction time.
I've been playing with more simulations and now think there's a simple alternative to blanking the HV supply module you've got (if you were still thinking of going that route). You should be able to use the module unmodified and unblanked, as below. The pic shows two scenarios, the only difference being the addition of diode D3 in the second scenario.
The contents of the dotted rectangle are a crude simulation of your HV module, and the Trigger is a crude model of the triggering coil plus whatever conditioning the coil signal needs. The SCR type is arbitrary but assumes a sensitive-trigger type.
Version A results in a single current pulse through the ignition coil: Version B results in a few cycles of oscillation (dependent on, inter alia, the duration of the trigger pulse).
The magic is performed by the 10k resistor, which limits the current drawn from th HV supply but is sufficiently low in value to allow the CDIcap to recharge to 350V between successive firings of the SCR (here at 100mS intervals, corresponding to 600rpm of the engine). Note that the HV voltage (trace hv2) drops only a volt or so.
Average current draw from the HV module is ~8mA; peak is ~35mA.
The contents of the dotted rectangle are a crude simulation of your HV module, and the Trigger is a crude model of the triggering coil plus whatever conditioning the coil signal needs. The SCR type is arbitrary but assumes a sensitive-trigger type.
Version A results in a single current pulse through the ignition coil: Version B results in a few cycles of oscillation (dependent on, inter alia, the duration of the trigger pulse).
The magic is performed by the 10k resistor, which limits the current drawn from th HV supply but is sufficiently low in value to allow the CDIcap to recharge to 350V between successive firings of the SCR (here at 100mS intervals, corresponding to 600rpm of the engine). Note that the HV voltage (trace hv2) drops only a volt or so.
Average current draw from the HV module is ~8mA; peak is ~35mA.
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