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0

As you would need to control mains anyway, you can connect only relay and lights in series. Existing switch you wire to GPIO of Arduino. This way Arduino know state of switch and can control lights without extra connections and sensors. There is a problem that your Arduino have to function correctly to control lights even if you only want to use physical ...


0

If you're not comfortable working with 120VAC (could be disastrous if you don't know what you're doing) then a mechanical solution is much safer. You're going to hate this, but for proof of concept you could hot glue a limit switch onto the faceplate underneath your light switch like the picture below (painting it white might make it more tolerable). I'd use ...


0

To get the functionality you describe, you need to have "3-way" (SPDT) switches — a manual one and a relay that the Arduino controls. This is just like having two switches that control the lights from either end of a hallway, except that one of them is controlled by your MCU. Sensing the state of the light is a separate matter. There are many circuits ...


0

Assuming you have two open pins, why can't you just drive the switch directly from your microcontroller? It's compatible with 3.3V and uses less than 10uA. The data sheet says the control signal pins will work with a signal voltage of between +1.8V to +5.3V and consume a max of 10uA. The datasheet also said you need to drive VC1 and VC2 pins opposite each ...


2

Yes, this product exists. It can be made using MEMS technology, as an electromechanical device (a relay with a fiber attached to the armature), or motorized (and probably other technologies). Important characteristics are fiber type compatibility (single-mode or multi-mode, and what core diameter) insertion loss return loss wavelength compatibility number ...


0

You don't want to be relying on a battery-powered circuit to actuate a relay that will kill the engine, if the battery is dead you lose the ability to stop the engine. Ideally a safety circuit is wired as Ron suggests so that is is failsafe and ceases operation of the circuit is opened, but that's not how stop switch on these engines work, they short a ...


2

I've never heard of a "pickle switch" but they seem to be a simple pushbutton on a cable. Figure 1. A pickle switch from AbelCine. To prove my theory: Disconnect the "pickle switch". Test for continuity with a multimeter on Ω range. Record resistance with button released. Record resistance with button pressed. simulate this circuit – ...


0

Functionally it doesn’t matter. The elements (LED and load resistor) are in series so the current flowing through them will be the same regardless of the order in which they're hooked up. That said, if the LED is driven on the low side I have a preference to put the load resistor from VDD to LED anode. Reason? Connected this way, if there’s a short to GND ...


0

You can use a relay rated for 240Vac and 30Vdc if you use an RC snubber design to limit V=LdI/dt and Ic=CdV/dt within the linear operating range. Since we do not know your circuit or cable impedances , I cannot specify what will work. But I am sure a design can be made to work that is well damped and limits AC voltages with 170V transients absorbed in an ...


2

The voltage rating of a switch is precisely about what how much of an arc it can break while it opens, and how much voltage it can withstand when open. Your switch must be rated for the maximum voltage that may appear across it. This is true of any single pole of a switch, so it doesn't matter whether the switches you are using are SPST or DPDT. In ...


0

There are many solutions. When you define cost and user interface, the choices get smaller...and smaller. When they go to 0, you change your specs'. There are binary analog MUX and mechanical rotary MUX switches if you search harder. Try here or here. You might even consider a pot' controlled current with a transistor. But learn to start with a functional ...


0

I would connect the two 0.1uF capacitors in your diagram between the signals and 0V. As they are now, any ripple on the 10V supply will be coupled to the signal lines.


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You could try something like this : simulate this circuit – Schematic created using CircuitLab The GND should be a return path, allowing the capacitors in the screen to detect a return path, similar to the one created by you touching the screen. This could not work if the leakage current exceeds the detection threshold of the capacitive screen, but ...


10

It means that the current for charging the Base is the same as the current used to discharge the Base capacitance when they do fall time testing. An exemplary circuit to do so is shown in this datasheet. You may also have a look at: How to determine BJT switching time


0

simulate this circuit – Schematic created using CircuitLab Figure 1. Redrawn circuit. I'm thinking V+ goes to the battery pack positive ... Correct. ... and Vout to the negative, ... No, VOUT is what drives the load. That's what's driving D1, the LED, in Figure 1. ... but I have no idea where the ground connection should go. In most ...


4

I know I did an analysis of this circuit not very long ago, but I can't seem to locate it now. The basic idea is that the two BJTs form a differential amplifier, comparing the voltages at either end of the MOSFET (drain and source). If the drain is even a tiny bit more positive than the source, then Q3 is cut off and the MOSFET is switched on. Otherwise, Q3 ...


3

simulate this circuit – Schematic created using CircuitLab Figure 1. Pump control circuit. How it works: As the tank empties the TOP switch closes first. When it passes the low-level switch it closes and RLY1 is energised. The pump starts via contact RLY1b. Meanwhile RLY1a bridges out MIDDLE so that the pump continues to run as the water level ...


1

Modify HDMI DPDT push button with an NPN to control with GPIO pin? It will be quite easy to modify, though there are two distinct circuits you need to drive separately. You will need to remove the DPDT switch to get correct remote operation. HDMI switches (with manual pushbutton selection) all use one of various HDMI multiplexers to change the TMDS/Clock ...


2

Not really feasible. Especially with the lack of design requirements, schematics and what you have tried so far. With that said I suggest that you desolder the DPDT switch and substitute the contact connections of a small DPDT relay. Use your GPIO to drive an NPN transistor that in turn drives the relay coil.


0

SMD/SMT is surface mount device / surface mount technology. This means that the component is soldered onto the surface of the board and the pins do not go into holes through the board. They will be somewhat weaker than straight ones that use through-hole connections, in that sideways or pulling forces are much more likely to break the component off of the ...


1

Straight usually means vertical pins that are perpendicular to the board with no bends in them. It also means that the connector is usually perpendicular to the board. Right angle are generally parallel to the board.


0

Can you directly control the driving power with only two switches? If the actuator is powered via only two wires where polarity determines the direction of motion, interrupting one or both wires via switch e.g. at the "low" position will disable any motion of the actuator, i.e. it will not be able to move away from that position again. You may be able to ...


-1

There are two currents for a relay, the carry current, and the breaking current. The carry current is dictated by the thickness of wires, the contact area in good contact, and by the resulting \$I^2R\$ heating that occurs. This should be independent of AC or DC current flowing through the relay. The breaking current is dictated by how fast the contacts ...


3

I'm assuming it means it only can carry 300mA or 0.3A at DC voltages. So you cannot use these directly with your actuator. You would need a circuit to take those switches and control a relay/mosfet/transistor to control the actuator.


2

Since they permit both AC and DC power for the LED, I suspect there's some sort of electronics that is pre-conditioning power for the LED. I would say, try it. Apply 6VDC to the LED and see what happens. If it works, try applying 6V reverse polarity, which is unlikely to harm a 12V LED. If it lights in both polarities, that cinches it, there is a ...


4

The datasheet you linked to covers multiple variations of the switch. I count 14 different part numbers. There are multiple voltages and colours. The note under the table states there is a resistor included in the switch and special voltages can be made to order. It is probable that the LED will light up on the 12v version if you apply 5v, it will just be ...


0

You only need to switch Motor Enable and Drive Select for B drive, so that's only two pins.


1

You may actually be able to do a lot better than having to switch 34 wires. Take a look at the floppy connector pinout: http://www.interfacebus.com/PC_Floppy_Drive_PinOut.html First of all, half of the wires are grounds, which you can just connect in parallel. Secondly, the cabling is actually designed for two drives to share the same cable, with a '...


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