Questions tagged [12v]
Deprecated tag. Do not use in the future.
654
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Can I charge my two large 12 V bus batteries that add up to 24 V together with a a 12 V solar panel?
Just wanting some way to charge my bus batteries while parked for a long amount of time besides a battery charger. But am having trouble figuring out what kind of solar panel to get.
My bus batteries ...
2
votes
1
answer
205
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What does a 9 A battery do to a 3 A motor when using the battery for movement?
I am trying to figure out why my battery keeps discharging so quickly. I have a 12 V, 9 Ah (valve regulated) SLA battery that I use on the bench to test motors. I write a small program, test the ...
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1
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37
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Control 12V 90mA alarm from 2N2222
I have an alarm rated for 12V 90mA. I want to turn the alarm on/off with a 2N2222. The base of the 2N2222 is connected to an ESP32. Circuit diagram is attached. Will it work?
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Can I solder two 12 VDC fans to one end of wires of single Molex connector?
I have 2 Sunon fans (12 V, 415/519 mA - max, 5.4 W/6.22 W - max). I want to solder both onto the end of a single Molex connector cable extension (bought from a local store).
Molex connectors all-4 ...
0
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1
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I need a 12v two way non locking toggle switch both sides must have a NC and a NO when switched on NC must open NO must close I'm not an electrician [closed]
2 way non locking toggle switch
both sides NO & NC
When switched NO must close NC must open
0
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2
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68
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Help with custom monitor 12 V adapter
I have an electrical question about a custom adaptor I want to build.
The monitor im using:
philips 258B6QUEB/00
https://www.philips.co.uk/c-p/258B6QUEB_00/brilliance-lcd-monitor-with-usb-c-dock
It ...
0
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1
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40
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Battery sizing question
I’ve got a 12 VDC vibration motor. It wants 2.1 A, listed as 30 W.
I’ve also got a 12 V, 12Ah battery I know to be in good working order. Initial current is less than 3.6 A.
Is that something that ...
0
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1
answer
37
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12 V power supply for blower motor
I'm looking for a power supply to run a small propane RV furnace. The furnace only draws about 5 A while operating, to run its blower motor and the electronic ignitor plus the circuit board that ...
2
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1
answer
50
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How to dim a 12V AC halogen
I have a couple of lamps, halogen I think. I bought them decades ago. When new they had a nice dimmer knob that led down to a transformer and I could dim the lights or, more usually, turn them off and ...
0
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60
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I am building a circuit that operates at 5 V but I need to use SIM7600 module @12 V
I am building a circuit with an Arduino that operates at 5 V, but I need to use a SIM7600 module that will be connected to the Arduino's pins, and needs 12 V in order to operate.
Will I have any ...
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98
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Protect GPIO pin on ESP32 development board from accidental 12 V input
I'm working on a project which involves connecting in series a lot of small cut strips (5-7 LEDs) of WS2815 powered by a separate 12 V PSU. They are controlled by GPIO of an ESP32 Dev Module powered ...
4
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3
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211
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Battery-powered 3-5 V MCU, but 12 V solenoids. How to power?
I'm building a battery-powered safe cabinet hobby project. It uses the 32L152CDISCOVERY board. I plan to charge it with a solar panel. I should operate at least 6 months without maintenance.
The MCU ...
0
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0
answers
92
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Overvoltage protection for RS485 from DC-DC voltage
I am making a circuit to protect RS485 against 24V and 32V DC over-voltage. Note that my power supply is 12V. I've done my research and found solutions, but I can't fake it.
More specification ,my ...
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1
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What is a suitable resistor value for this circuit?
See the small circuit of a PIR motion sensor below. I've tried to find more than one circuit online but every single time it shows a different value for the resistor.
I would be grateful if anyone can ...
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How to regulate a battery + solar panel setup so it’s under 12 V?
I am making a remote controlled driveway gate and the problem I’m having is the battery/solar panel together is putting out more than 12 V at times and frying my remote controlled relay board which is ...
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68
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Replacing SPDT relay with MOSFET
I'm having trouble replacing a SPDT relay with a MOSFET circuit.
I have an SPDT relay that serves as an emergency brake of a small motor when the power goes off, shorting both motor inputs.
It's slow ...
0
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1
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61
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12 V, 7 Ah equivalent transformer
I am trying to power a maglock. The specs say its current draw is 12 V, 500 mA.
It works fine when powered by a 12V battery (Mighty Max ML7-12).
However, it doesn't work when powered by a 12 VDC, 2A ...
0
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1
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140
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How to use TVS diode for Overvoltage Protection while powering Arduino on Vin Pin?
I am trying to make a protection circuit for Arduino nano to protecting overvoltage. Normally if I powering "Clone" arduino NANO with 12 Volt, Arduino nano is starting to smoke. So I've ...
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2
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68
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DC 12V automatic power transfer system to supply Wi-Fi and ONU
I'm from Ukraine, so there are very few options to test something and get support.
I need to power my Wi-Fi router and fiber optic modem when utility is down. It is available 4 hours by four down. Wi-...
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4
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182
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Relay gets extremely hot
I have to programmatically switch a 50 W load (20 V, 2.5 A) and I'm using a Bosch DC relay to do it (exact part is pictured; see page 6 of the datasheet).
When I apply 12 VDC the relay clicks, so ...
1
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2
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67
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Burnt out 12 V switch?
I am trying to get a tailgate release button to work on my pickup truck. The problem I have is the switch burnt out. Am I running too much current through it?
I have attached a picture of what my ...
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1
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85
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Why is this 2 pin 12V mechanical flasher relay on continuously instead of flashing?
+12V is connected to the B terminal, and one end of a regular bulb is connected to the L terminal, and other end of the bulb is grounded, butthe bulb does not blink at all. It is continuously on.
What ...
4
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2
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774
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Relay buzzes because voltage increases to 12 V over time rather than immediately
I'm trying to fit an internal light to a campervan that switches on when the current internal lights that are are factory fitted come on.
I'm trying to use a relay for this so that when the factory ...
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0
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55
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Converting vehicle instrument cluster lights to LEDs: one light stays on
I have a 1998 K1500 (GMT-400) and I would like to convert the lighting in the instrument cluster to LEDs. There is a semi-known issue with this type of vehicle, where if an LED light is used for the ...
0
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1
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147
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Maximize heat from a 12 V, 100 W solar panel and 26 AWG nichrome wire
I am heating a nonconducting material. The power source is connected directly to 12 guage copper wire. One 30 inch strand of 26 AWG nichrome 80 wire runs between the copper wire posts.
Since sunlight ...
2
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2
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202
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Powering long LED strip, injecting power. Correct way to fuse?
Recently I asked an opinion based question regarding LED strips. I have learned my lesson and now I have an actual question regarding "how power flows".
I'll explain: I have a lighting ...
0
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1
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84
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Get 12 V stable output from solar connected 12 V battery
I have a 12 V monitor on my sailboat that only accepts a 5% voltage difference, so it needs between 11.4 V and 12.6 V input. Max draw is 1.5 amp according to spec. Here is a link to the user manual: ...
0
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32
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Sparking when touching terminal on valve
In an effort to protect my relay I have added a diode for flyback protection. However when I touch the second terminal with power from the circuit I see a small spark. The source voltage is 12 volts, ...
2
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2
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127
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Control AC load via relay with DC trigger?
The headlight of my motorcycle is AC powered via stator.
I want to switch between Hi/Low beam using a single pole double throw (SPDT) NC relay.
Power to pin 30 (AC)
Ground to pin 85 (?)
Trigger to pin ...
0
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2
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71
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Load independent LED flasher DIY advice
I found a product that does something very similar to what I'm trying to DIY.
The product purposefully combines a load independent digital flasher relay and electronic push-button controls. Depending ...
0
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2
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90
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Low voltage connector identification?
Can anyone identify the female and male connectors in the picture? Thanks
Here are some more pics Thank you.
1.56mm from pin to pin. So it should be a JST 1.25mm 2 pin micro?
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115
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Identification of polarized 2-pin connector used for low voltage lighting
I am currently working on some outdoor low voltage wiring/lighting for our house. I received some NOS high quality fixtures that I hope to use IF I can figure out what connector this is on the end of ...
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62
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12V boat lead acid battery suddenly failed
Battery on boat and powered by solar panels started acting really weird suddenly exactly a week ago. App shows voltage went from minimum 12.3V to min 6V in a day. On board voltmeter showing 11.9-12.2 ...
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3
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424
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12V DC motor takes substantial amount of current when the direction is reversed
I am working on an underwater ROV. I am running four 12V DC motors using an Arduino Uno and four N-type logic level MOSFETs to control the speed of each motor individually. There are also four 12V ...
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88
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Can I power a router that requires 12V-DC via a 5,5mm input by using a powerbank that can output 12V DC over USB [closed]
I have a powerbank that can output 5V-3A/9V-2A/12V-1,5A over USB. The router I would like to power came with a 12V-1A adapter and uses less than 12W. If I were to buy a USB to 5,5mm adapter cable, ...
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2
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96
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How to test if current reading functionality on multimeter is working
I have a new multimeter that I've tested the voltage of a 12v flooded lead acid battery with before.
Today I tried to test the amps running on the battery, to see if there was parasitic draw. As ...
0
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3
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Is it acceptable to connect a car battery and an AGM battery in parallel?
I power a 12V fridge in my car either via the car battery (when the vehicle is running) or via an AGM battery. There is an Anderson outlet in the car connected to the car battery to which I attach a 3 ...
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Is 3 amperes at 5V drawing the same power as 3 amperes at 12V?
I know that amperes are volts x watts. If I draw 5V at 3 amperes, is it almost the same as drawing 12V at 3 amperes from a 12V system? I expect the 5V would draw more as there is inefficiency when ...
0
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2
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101
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How to regulate voltage from marine battery? [closed]
I have a telescope with a number of components that run on 12vdc.
I want to create some sort of power regulator to supply power to my components without frying anything. Is there some kind of voltage ...
0
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1
answer
83
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What type of circuit/components are needed to make a phone charger that stops charging when the battery is full?
I'm building my own portable power station, using a 12v lead acid battery as a power source. Currently I've got 1 12v socket and 2 usb ports on it. The idea being to use it to power something like a ...
0
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2
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75
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DC motor to start and park in the same place with timer
I am trying to make a 12 volt DC motor start and stop with a timer. It needs to park in the same place every time. I am also using a double pole double throw micro switch.
How can this be ...
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1
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336
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How to get 12V 2A power through an extension cable?
I have an AC to DC (12V, 2A) converter (/transformer) plug which I am using to power a wireless router. The connector has "center positive" polarity and the size of the connector is the ...
1
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1
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89
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Switching ATX PSU with a NPN transistor controlled by a 12V signal
I searched everywhere but I can't find a circuit to turn on a PSU with a 12V signal.
I know that PS_ON has an internal pullup but its value may change by vendor.
So I don't know if I can use this ...
0
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1
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318
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Step down buck converter - lower input voltage than output - LM2596
I want to power 5v leds from a 12v source in my car using a "DC-DC Adjustable Step-down Buck Converter LM2596 3A". The source has a dimmer switch which can regulate the voltage from 12v to 1....
2
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2
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69
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12 V initial to lower voltage continuous step-down circuit
How do I design a step-down circuit that hits 12 V initially, but then drops the voltage for continuous use until turned off?
I have a line lock solenoid that requires 12 V to activate. The ...
2
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1
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124
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How to get a steady 12 V output from 12-15 V source?
I am working on a project with a variable voltage input 12 - 14.6 V.
I need a constant 12 V output to power some 12 V LED strips. I’m running this through a home automation board and will be ...
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123
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Replacing 12V 19AH lead acid battery with 12V lifepo4
I have a Stanley PPRH7DS battery charger that came originally with a 12V 19AH lead acid battery. This battery has since given up the ghost and I am looking to replace it.
Last summer I constructed a ...
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130
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Grounding microcontrollers, signal and logic level wires in a vehicle with buck converters
I sketched out my main installation in my project vehicle. To summarize, it runs with isolated DC converters, one gets the input from main battery (standard 12V lead acid) and converts it to clean ...
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1
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171
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Running and grounding paired shielded cable thru a connector
I need to run two logic signals around a vehicle, so for good measure, regardless if its overkill or not, I want to use a shielded single pair wire for that job. At one point it should be crimped to ...
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51
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Grounding sensitive devices (ICs, logic level switches) in a vehicle (generator and battery) environment
In my project vehicle I will be using a buck converter that can take from 9 to 18V and output clean 12V. I will also need smaller regulators (12v to 5v) for couple of microcontrollers. I've heard ...