New answers tagged dc
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Finding current using Kirchoff Law, but getting unsolvable system
Here is an alternative for solving the circuit.
Made with Maple sheet. Used 2nd picture of OP question. Use eq6 OR eq7.
Made with microcap v12
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Level Shifter design. 0-10vdc to 0-24vdc using pnp transistor
For level-shifters where the voltages involved are well above 5V (ie: above normal IC logic levels), I prefer to use discrete designs based on a differential pair input stage followed by a logic ...
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Level Shifter design. 0-10vdc to 0-24vdc using pnp transistor
4v7 zener as comparator, 2n3904 as inverter and 2n2222 buffer.
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Level Shifter design. 0-10vdc to 0-24vdc using pnp transistor
Since you've added that you can use NPN transistors, this is a reliable way to do what you request. If you can invert the input by some other means you can eliminate Q1 and R1 (connect R4 to Q2 base).
...
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Level Shifter design. 0-10vdc to 0-24vdc using pnp transistor
The solution is a circuit similar to the one posted by Jens, but delete one resistor and add one 18 V zener diode. This prevents the transistor from conducting when the input is high.
When the input ...
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Level Shifter design. 0-10vdc to 0-24vdc using pnp transistor
With these resistor values the output voltage changes at an input voltage of around 8 V.
If SW1 is open or V1 is at 0 V the base current of Q1 is high enough to provide close to 24 V at the PLC input (...
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Multimeter Range and Resolution
Your meter uses a DVM, digital voltmeter, module with a range of -199.9 mV to +199.9 mV (or ±0.2 V in round numbers). These are known as 3½-digit displays, the leading '1' being the ½ digit.
simulate ...
- 171k
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how to fix Heating issue of 7805?
Since you have an LM7805, and a 12V supply, and I assume you don't want to replace everything, I'll try to show you a fix with minimal changes.
First understand that anything passing a current, with a ...
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Building a power supply for a Raspberry Pi 4 but having trouble with the output voltage of regulator
You are using a linear regulator (type of regulators, not the manufacturer).
For a 3A output these require 3A input.
And that means to have 15W output, it requires 36W in, and dissipate the remaining ...
- 137k
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Is negative voltage going to cause trouble?
If this exactly happens with a real circuit, too (not just simulation), it means the "NOT gate" does not have a clamping diode in the input. It's very common for a gate to have this in the ...
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Repurpose adjustable standing desk linear actuator for a project on my truck
You’d need to have a close look at the circuitry; it’s quite possible that the actuators run on low-voltage DC and the control circuit certainly will. If you’re lucky you’ll find that there’s an AC ...
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Do you put a ferrite bead on both the positive voltage and GND trace?
You generally want each connection to the ground node to be as low impedance as possible to every other ground node. Ferrite beads are inductors, so you're introducing an inductance between two points ...
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Would 5.5 x 2.1 mm female plug work inside a 5.5 x 2.5 mm male jack for DC power?
Not all plugs are created equal. Some plugs have full, uniform tubes that have little tolerance, and a nominal 2.5mm center pin will not fit inside one designed for a 2.1mm pin. They look like this:
(...
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Can I give DC 12V to a AC 12V input?
Linear regulators like 7812 needs 2v or more above the output voltage as input in order for them to work properly. Example, you want a regulated 12v dc output, you have to at least give an input of ...
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Electronically activated circuit breaker
You already have a circuit breaker, right?
They make various types of actuators for these. They're basically an electromagnet that moves a little lever that flips the breaker down. There are also ...
- 72k
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XL6009 boost converter as 8V camera (DSLR) external power supply - camera not turning on
The reason the camera is probably rejecting turning on with the XL6009 boost converter is that the dummy battery includes more than just the boost converter. The battery has internal thermistor, and ...
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How to connect a 12V electromagnet to 220V power adaptor
Should I use a lock that releases on power-on or power-off?
You have a couple of considerations:
The lock should last much longer if it is only powered for a short while. Energise-to-release would ...
- 171k
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Do Kirlian setups work with DC power?
According to this paper, Kirlian photography will work with DC.
There's mention of some differences between Kirlian pictures made using AC and Kirlian pictures made using DC.
The polarity of the ...
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Using a capacitor to handle the inrush surge power of a fridge
You're likely to need quite a large capacitor to start the fridge, but not as extreme as those capacitor banks you see people use for starting cars.
But the first thing to check would be to try the ...
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Can I convert 12 V DC to 24 V DC using a 2N2222A?
S7-1200 has IEC Type 1 sink inputs so you need to provide current of nominal 4 mA 24 V at the input (minimum 15 V).
One way to do that is with two transistors:
simulate this circuit – ...
- 384k
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Can I convert 12 V DC to 24 V DC using a 2N2222A?
If you can accept inverted logic into your PLC, this would do it:
simulate this circuit – Schematic created using CircuitLab
If you can't have inverted logic, use two:
simulate this circuit
...
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Calculations of mesh and nodal analysis of my dc circuit doesnt satisfy any of the KVL or KCL conditions
Analysis of the given circuit with various methods.
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Can a 6V DC circuit turn on a separate/unconnected DC circuit?
The inductor doesn't do anything visible to the circuit it's a part of. It does still produce a magnetic field (which will be contained within the shielding of shielded inductors, so you need an ...
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Can a 6V DC circuit turn on a separate/unconnected DC circuit?
Can a 6V DC circuit be configured switch on a second, and separate, 3V DC circuit?
Yes. There's numerous ways to do that: relays, octocouplers, and a few other things are giving you an isolated ...
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Calculations of mesh and nodal analysis of my dc circuit doesnt satisfy any of the KVL or KCL conditions
In your LOOP 2 equation 3rd line it should be +50I3 at the end of the LHS of the equation. You need to multiply throughout by the negative outside the bracket in the previous line.
In the equation for ...
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Calculations of mesh and nodal analysis of my dc circuit doesnt satisfy any of the KVL or KCL conditions
For KCL, always draw all current directions either entering the node or leaving the node. This will always work, if the current determined later is negative, then the actual direction is opposite the ...
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Calculations of mesh and nodal analysis of my dc circuit doesnt satisfy any of the KVL or KCL conditions
Maple sheet (i1, i2, i3 are your "circulating" currents, first diagram).
Made also using Thevenin 2 times. R3 is "external" resistor).
You have another alternative way for finding ...
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Safe to use a common return for multiple DC power supplies?
It is safe, but you may have common mode voltage problems on ground as the ground will be shared by all devices. This means you need to think about how much resistance the return path has and how much ...
- 78k
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Which is the correct flow of current in these following circuits for nodal analysis?
Learning to draw
From your earlier question and this one I think I'd recommend gaining some practice redrawing schematics in different ways. Some schematics are the logical equivalent of a Gordian ...
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Which is the correct flow of current in these following circuits for nodal analysis?
Normally, for DC (or instantaneous), current is assumed to be flowing from higher potential to lower potential.
But for analysis, there's no "correct flowing direction". You just pick a ...
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How can I amplify an analog DC voltage signal?
Simply use this circuit with a 24 V supply already you have.
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How can I amplify an analog DC voltage signal?
Subtract 0.6V and scale by 9 and add 1V.
Or in math terms:
VOut = (VIn - 0.6V)x9 + 1V-> Vout [1;10]V with Vin [0,6;1,6]V
Or in circuit terms:
simulate this circuit – Schematic created using ...
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