More than one of a thing, performing the same task simultaneously

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0
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1answer
41 views

Is my DIODE in PARALLEL with the Relay (to protect input)

this is my circuit (the path / "read" is from 1 row to N row): The GREEN wire (from 17 row) is the DATA from a Raspberry (ANOTHER GREEN wire enter in 11 row - resistor in serie - and is connected ...
2
votes
1answer
46 views

Parallel differential signals

I need to send some I2C data through RJ45 cable between Arduinos. One ATMEGA2560 as master and 1-4 328P's as slaves. I've seen some different configurations and I think for my application the solution ...
0
votes
1answer
32 views

Can I wire the secondaries of 2 high-voltage transformers in series safely?

I have two 6kV, 30mA Neon Sign Transformers, and I want to get 12kv or higher at 30mA or less. I know you can wire in series to get that effect, but is it safe for the transformers? Obviously, you can ...
0
votes
1answer
39 views

Li-ion and Lipo battery in parallel connection , can they work simultaniously?

I have a Li-ion battery(3.7V and charging Voltage 4.2V, 1800mAh) and I bought a Lipo battery(3.7V and charging voltage 4.2V, 2500mAh) for my smartphone. And I want to create a homemade battery case. ...
1
vote
4answers
196 views

Different voltage drop in serial and parallel circuit with resistor

I have a circuit powered by 9V battery, I'm using two 2V LEDs. If I connect the LEDs in series with 10k Ohm resistor, the voltage before resistor is 9V, after the resistor it's 3.3V and after the ...
3
votes
4answers
299 views

Short life of LED parallel to Solenoid as indicator

I have a relatively simple circuit: 12 V to a switch; on the other side of the switch is a solenoid and an LED in parallel. Nothing special about either component; the LED is a 20 mA typical LED rated ...
3
votes
4answers
138 views

Why use FREERTOS instead of the interrupt mechanism on a microcontroller? [duplicate]

This might be a very stupid question. I have experience with embedded software on bare-metal and just started with FREERTOS. However I don't really understand why one would use FREERTOS instead of ...
1
vote
1answer
32 views

Battery Pack Configuration

I currently am using Li-FePO4 cells in the configuration below (picture): I'm researching how to build a passive cell balancer for this battery pack. Though I'm getting confused on some specs I'm ...
0
votes
4answers
123 views

Why is there current flow in the sub-circuits?

I'm struggling with the theory of this(unusual) circuit: simulate this circuit – Schematic created using CircuitLab The load receives no power at all, due to the voltages cancelling out, ...
-7
votes
1answer
36 views

How to find the current in a complex circuit with nodal voltage sources?

This is circuit. Not sure how to get V, and find current. Any help?
0
votes
2answers
118 views

Why multiple capacitors in parallel? [duplicate]

Wondering why you would choose to use smaller capacitors in parallel vs one bigger one. Here's an example: Multiple in Parallel Page 4: One larger C Is this a component size and track width choice?...
-2
votes
1answer
51 views

Find the total resistance of circuit with both series and parallel resistors

I found this circuit in a textbook, but I'm having a difficult time calculating the total resistance here. I tried using the formula for parallel resistors with the 3 resistors the the upper left, and ...
-2
votes
2answers
136 views

how to calculate voltage drop by a resistor/ circuit attached parallel to another resistor/ circuit?

On my battery eliminator, if I measure source voltage without any load, it gives the correct voltage. But when I add a load, the voltage drops. And if I short-circuit the 2 output-leads with a ...
0
votes
0answers
35 views

Finding the current through resistor in source free parallel RLC Circuit for t>0

My solution: Since alpha >w0, so response is overdamped. Current through inductor:$$ Il(0-)=Il(0+)=6 $$Voltage across capacitor: $$Vc(0-)=Vc(0+)=0V$$ Current through resistor: $$ Ir(t)=A1e^{s1t} + ...
0
votes
1answer
58 views

why add a resistor parallel to voltage source? [duplicate]

Sometimes I see a resistor parallel to voltage source (such as image below), isn't it completely useless ? Edit: I see the other similar question now, but I think it doesn't have the right keyword ...
0
votes
4answers
114 views

Large parallel strings of LEDs

I want to drive multiple strings of XTE LEDs (total of ~36 LEDs). The relevent (-ish) specs are as follows: I_f,max = 1.5 A Desired I_f = 0.5 A V_f = 2.94 V (0.5A @ 85C) According to some ...
1
vote
1answer
49 views

Multiple DC Voltage sources in parallel

I'm building an alarm system (paradox EVO192 with ZX8 extension modules) and was hoping to have separate sections of the system each powered by it's own battery backed up power supply (something like ...
3
votes
2answers
51 views

Parallel input to serial output

I have been learning a bit about electronics. In particular I have been playing with the shift register 74HC595. Here I understand how bits are moved into the register serially, that is one bit at the ...
0
votes
2answers
72 views

What is the difference between charging batteries in series and parallel?

For example, if I have a charger that supplies 300 milliamps: Will it take a bit more than 3 hours to charge a 900 mAh AA battery? What if I have 4 AA batteries in series? Will it still take 3 ...
13
votes
3answers
366 views

How many MOSFETs can we safely parallel in condition of very high currents? I had problems with a motor application at 48V 1600A

I tried with some configurations in which 16+16 MOSfets of 240A each (really they are case limited to 80-90A because of source terminal, but i doubled this termminal with a very thick copper wire for ...
0
votes
1answer
19 views

AC voltage regulator in parallel

I have two voltage regulator which works on ac. They are both the same model and provide a maximum power of 3000w. I would like to plug their outputs together to make a 6000w total voltage regulator. ...
1
vote
4answers
71 views

Basics physics question about calculating resistance

Why is the total resistance calculated differently when resistors are in parallel, compared to when they are in a series? For example, $$ \dfrac{1}{R_t} = \dfrac{1}{R_1} + \dfrac{1}{R_2} + \ldots + \...
1
vote
3answers
159 views

Two identical DC power supplies in parallel for redundancy?

I'm trying to design a power backup system for my saltwater aquarium. In short, the system will be powered by a 12VDC power supply while the mains power is on. On power failure, the system will ...
1
vote
1answer
69 views

What happens if you put two coils in parallel

I want to build an LC-Filter from a tutorial I found (German language, if anyone is interested, I'll add a link). In that tutorial, a 330uH Coil with a max amp of 1A is used. I have some 330uH ...
0
votes
1answer
47 views

How to sum resistors in parallel and series?

I know how to add resistors in parallel and resistors in series, but i don't understand how to differentiate between resistors in the format shown: simulate this circuit – Schematic ...
-1
votes
1answer
44 views

What resistors to use for 60, 8000mcd LEDs, with 4 * 1.5v battery source? [duplicate]

I currently have 60 LEDs in a parallel circuit. I am using 4 1.5v batteries as the source. The LEDs have a forward voltage of 3v-3.4v (8000mcd, wavelength 460nm). My questions are: Can I just use ...
1
vote
1answer
64 views

Parallel connection of two 2-ports

In the N-port theory, it says that the total admittance matrix for the parallel connection of two 2-ports is the sum of individual admittance matrices "if it is possible to connect them in parallel". \...
0
votes
3answers
120 views

When will parallel LED voltage drops become an issue

The following circuit will cause problems because of voltage drops: simulate this circuit – Schematic created using CircuitLab It should be changed to look like this: simulate ...
3
votes
1answer
86 views

Is there a limit to the number of parallel LED if each has its own resistor?

I am building a circuit with 6 parallel LEDs, powered by 5 volts through a transistor array which can provide 300ma. If each LED is allowed 20ma (by setting the correct resistance for each), I should ...
-3
votes
1answer
54 views

Maximum inductance of parallel circuit [closed]

Three inductances, 1 henry, 2 henry and L henry are in parallel. Find value of L such that the equivalent inductance is maximum. At this value of L, what is the value of equivalent inductance?
0
votes
1answer
141 views

diode and resistor in parallel with resistor

how do you calculate V\$_{R3}\$ in the circuit below? V\$_{in}\$, all the resistor values and the type of the diode are known. By simulating this circuit one can see that V\$_{D}\$ is increasing ...
0
votes
2answers
76 views

voltage divider in series and parallel circuit

I have these two series and parallel circuits and I want to know how I should find the voltage through R1, R2, R3 and R4. I know I should use the rules of voltage divider but I don't know how when I ...
1
vote
2answers
91 views

How do I calculate voltage using the complete diode method?

Doing extra examples for a electronics class, came across a section uses the Complete Diode Model (We haven't covered it in class in much detail, only the definition). The question is: Determine the ...
0
votes
0answers
37 views

Operating different current batteries in parallel with a UPS

I have a 24V UPS and I use a pair of 12V batteries in series, each with the same current rating (130A). Often I charge the batteries with an external 24V charger to achieve a faster charging time. I ...
1
vote
0answers
52 views

Wiring 2 audio output transfomer secondaries in series or parallel

I want to know if wiring 2 audio output secondaries in series is doable. See problems with this schem? Would parallel be a viable alternative?
0
votes
2answers
50 views

Connecting power sources in series or parallel?

Basic question: Lets say i have two power sources, one supplying 1V and 100mA, the other supplying 2V and 200mA What would be the difference if i connected them in series or in parallel? As far as ...
0
votes
1answer
42 views

parallel rlc voltage source

I am learning about circuits and I have some questions regarding circuit initial condition: - no initial energy stored before switch is closed - there is current at L1 at t = 0- I am wondering: ...
0
votes
3answers
103 views

Should I wire my electrical actuators in series, parallel or a combination of both?

I'm working on a project that requires four (4) electrical linear actuators to work together. They must be driven at the same speed, simultaneously. Let's assume that I have four identical actuators ...
-1
votes
1answer
58 views

Circuit redraw. Series and parallel resistors [duplicate]

I just wanted to ask you if I redrew the circuit correctly and if you could help me what to calculate first or if you could help me to redraw this circuit even simpler. And to tell me a few tips for ...
0
votes
2answers
67 views

Equivalent resistance of resistors

Can somebody help me solve this. I need to find the equivalent resistance of these resistors. I really don't know where the trick here is. If somebody could help me I would really appreciate it
-4
votes
1answer
81 views

Series parallel resistor. Circuit redraw

Can somebody help me redraw this circuit so it'll become easier to see what resistors are in series and what in parallel. Thanks in advance Have I redrawn the circuit correctly. Are R1 and R3 in ...
1
vote
1answer
243 views

eMMC interface : Parallel vs SDIO

I want to use an eMMC card for my application. After searching on different websites,I was not able to find any parallel interface supported eMMC chip. Is parallel interface available for eMMC chip?...
10
votes
4answers
830 views

Why do we use two parallel capacitors in a voltage regulator circuit? [duplicate]

C1 and C2 are parallel capacitors and their total capacitance is 1000.1 uF. I think C1 is ...
-4
votes
2answers
111 views

Wiring 5mm IR LEDs in parallel [duplicate]

Im trying to wire 9 5mm IR leds in parallel using a 9V battery. the forward voltage is about 1.5 and Im looking for about 100mA instead of the ussual 20mA with a standard LED. When I punch these ...
3
votes
2answers
128 views

What Circuitry is needed to charge in parallel, but power in series?

simulate this circuit – Schematic created using CircuitLab I've read several other battery posts, and didn't find the answer I was looking for. My question is, can the Diagram I've provide do ...
2
votes
3answers
120 views

LEDs in parallel [duplicate]

If I have 4 identical* LEDs wired in parallel to a single resistor so that the overall current available is 30 mA, do I still run the risk of premature burnout? The LEDs peak forward current is 30 mA. ...
0
votes
1answer
80 views

Can devices be added in parallel indefinitely?

I'm assuming not, but say you added devices with the same resistance in parallel. All I've learned is that they would receive the same voltage and the current into and out of the voltage source would ...
1
vote
1answer
29 views

Photomultipliers in Parallel

I have a photo-multiplier going into a preamp then two stage shaping amp (PC250 and PC275 board from Amptek). The photo-multiplier is attached to a plastic scintillator and then a beta emitting ...
-3
votes
1answer
135 views

I want to use many parallel LEDs. Can this IC (BP3309) help me to control them? [closed]

I want to use many parallel LEDs. Can the BP3309 IC (datasheet in Chinese) help me to control the LEDs? I want consistent brightness.
2
votes
2answers
116 views

Help to join 3 resistors in parallel into 1 (power equiation?)

I want to join 3 resistors connected in parallel into one. Like this If for the total resistance I use Rt = R/3 But what about the power of them?