Recent content by TheRedDevil18

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    Positive displacement pump for spray nozzles

    Hi gmax, unfortunately that's the pump I was given to work with. I could probably slow it down with pulleys else yeah its just a waste of power. Coming back to the datasheet, to calculate the motor horsepower, the equation they gave is, I know my motor rpm and the flowrate the pump can...
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    Positive displacement pump for spray nozzles

    It's the D10-X. Are you referring to the one in the catalogue ? I believe I will need a flow control valve with 3 ports. Inlet, outlet and discharge excess to tank. I need to take the flow down from 30 L/min to 1.5 L/min. I think they call it a back pressure regulator ?
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    Positive displacement pump for spray nozzles

    Hi all, I have a positive displacement (diaphragm) pump that I am looking to use to supply spray nozzles. The pump has a max pressure rating of 69 bar at 30.6 L/min (1450 rpm). I however want my nozzles to spray at 15 bar pressure and from the nozzle performance data sheet that equates to 0.68...
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    Air conditioner fan not starting

    I have a problem with my air conditioner fan not starting. As seen from the schematic below, when I test for voltage between the brown and black wires, I get 0 V (this is the problem). The indoor unit isn't sending the control signal to turn the fan on. The compressor powers on fine though. When...
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    Electronic circuit breaker design

    I was reading about TVS diodes, would be easier to use one of those instead of a snubber circuit. How well would a tvs diode work ?
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    Electronic circuit breaker design

    Ok, I saw that video you posted, and they say one of the solutions is to trip on a current zero. Since I have my current transformer, I can make a zero cross detector going to my MCU so I know when to trip ?, and maybe also a snubber across the terminals for added protection ? They also say...
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    Electronic circuit breaker design

    Saw this circuit breaker which uses a microprocessor similar to my design https://stevenengineering.com/Tech_Support/PDFs/45CBEIIC.pdf On page 9 of the breaker above, they take a sample of the full cycle and calculate the true rms. That would mean for a 50 Hz wave, a time of at least 20 ms...
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    Electronic circuit breaker design

    I am just a student studying engineering :) This is one my projects that I have to do
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    Electronic circuit breaker design

    So that would mean calculating the short circuit current of the transformer primary ? Would a snubber work to quench the arcs across the relay contacts ?, I was also thinking of using an optocoupler and triac instead of the relay (since there will be no arcs) though it seemed to be a bit slower...
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    Electronic circuit breaker design

    I don't quite understand, can you maybe explain a little more please ? Its the max load current, and yes it must interrupt short circuit currents also
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    Electronic circuit breaker design

    I am looking to build a 10A circuit breaker using a microcontroller. It will have programmable current and trip time settings. It doesn't have much requirements besides what I just said. From what I know, if I use a relay then their is going to be arcing across the gaps, so I tried using a...
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    Electronic circuit breaker design

    Also, would it be better to find the true rms instead of the peak ?
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    Electronic circuit breaker design

    I'm trying to use a triac and optocoupler design like this, Though, it ends up being slower than the relay. Maybe because it waits for the zero crossing before tripping ?
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    Electronic circuit breaker design

    I wanted to use a solid state relay but they are really expensive. I will look into a termal fuse, thanks
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    Electronic circuit breaker design

    Ok, so basically that depends on my relays current breaking capacity. I checked the datasheet and it says nothing about the contact breaking capacity, Datasheet http://www.megasan.com/service/pdfhandler.ashx?fileid=3385 How well would a snubber work in suppressing the arcs across the relay ?
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