Questions tagged [12v]
Questions relating systems powered by a 12 volt supply. This may include automotive systems and lead-acid batteries that are nominally 12 volts although be aware that under many conditions the actual voltage may be several volts higher.
500
questions
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1answer
40 views
Parking Light And Signal light with same LED using MOSFETS
I have a project where I have an existing 12v parking light and I want to also have the turn signal use the same light. I've constructed a circuit using 2x NMOS and 1x PMOS. I think it will work and ...
0
votes
1answer
32 views
Get signal from apartment intercom to know when someone ring
In my apartment I have an old intercom to know when someone is at the entrance of the building and to unlock the door. I waned to connect it to an esp8266 to let me know remotely if someone ring and ...
0
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1answer
30 views
Polarities of high current bypass, and short circuit protection, transistors on LM7912 - NPN or PNP?
With reference to Olin's answer to Connecting Voltage Regulators 7812 in Parallel for High Current, and likewise the examples from the Fairchild, TI and ST datasheets, a PNP transistor is used (i.e. ...
0
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1answer
33 views
What is the correct wire size to run to a 12V 1.5 amp window blinds motor that is 47 feet from the DC transformer?
I read somewhere that an 18/2 wire could be used to connect a transformer to my window blinds motor (12V 1.5 amps). However, it didn't say anything about the distance. Since I am running it inside ...
0
votes
1answer
64 views
Use one 12V 30A timer for two separate 12V inputs?
I'd like to use the following timer, rated 12V 30A, but for switching two different 12V inputs at the same time and not having to buy and program two timers. But the timer only have one channel.
One ...
0
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1answer
69 views
2n2222 with 12v 8mA [on hold]
I have a circuit running on 12v 8mA and I want to get a signal to a GPIO of an esp8266 when current is running. So for that I tried to use a 2N2222 transistor with vcc of the circuit going to the base ...
0
votes
1answer
31 views
Wiring 4+ 12v led ring switches from one 12v supply
I am new to electronics and general electronic circuits. I have 4+ led ring switches (from here: follow link)
The website says that the rating of the switch contacts is 5A 250VAC with an ...
1
vote
1answer
41 views
Powering high-power laptop from DC without inverter
Context: We live full-time in an RV (a travel trailer) while traveling around the US. We have 300Ah of 12V Lithium batteries, a 3,000W inverter and 600W of solar. Although we have an inverter, it has ...
0
votes
1answer
43 views
Dupont jump wire in order to replace 20 pin cable
Hello, I bought a mp5 player for my car and I didn't find the 20 pin cable for this player. My question is if I could replace it by Dupont jumper wires as the picture shows
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0answers
95 views
12V voltage regulator
simulate this circuit – Schematic created using CircuitLab
I have bought the LM78H12K 12V voltage regulator, for the 12V output. My input voltage is 17 V DC, but unfortunately this component is ...
0
votes
2answers
52 views
Case Fans in DC
I need to run about 15 12V case fans(80mm) from wall power. How do I do that? How much amperage do I need? Which voltage adaptor do I buy? I have searched this site and many other sites such as this ...
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0answers
64 views
Boost 12v battery cranking amps with supercaps
I have a setup where a 12V AGM battery is powering an inverter. This inverter, for brief periods (1 or 2 seconds - compressor starting) needs more amps than the battery can provide.
Is there a ...
0
votes
2answers
52 views
Powering WS2812b 12V
I have an idea to use WS2812B as animating light on some old equipment. And I have some doubt. The equipment is 12v so I want to use WS2812B directly on 12V, namely I want to use 5 WS2812b in ...
0
votes
1answer
84 views
Confusion regarding a 12V DC motor's RPM
I have a 550 DC motor of 12V, 45W and 10K RPM installed on a wheel, which is not causing the wheel to turn fast enough when the motor is connected to a 12V battery.
I replaced the motor with an older ...
1
vote
1answer
46 views
Create circuit for 12v auto washer pump to 230v mains with push button for art installation
I am creating an interactive art installation in a gallery context using a 12 volts car headlight/windshield washer pump. It basically is a fluid washer pump taken outside of a car into a gallery, ...
1
vote
1answer
78 views
Help me understand my campervan split charge relay
I am new to the world of electronics, but keen to learn. The below all relates to the 12 V circuit of my van.
I have picked up a campervan which has a second "leisure" battery which powers items in ...
8
votes
4answers
1k views
Is there a way to tell what frequency I need a PWM to be?
I have a 12V DC motor that turns at 60 RPMs or 1 Hz. Do I need a PWM that matches the frequency in order for it to work? Most of the ones I've seen are around 25 kHz for a 12V 20A motor.
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0answers
41 views
why wouldn't a 9-60DCV 20A PWM motor control work to control a 12v 20A wiper motor [duplicate]
I have a question regarding controlling the speed of a wiper motor with a PWM vs wiring in a rheostat in the positive side. I have a 110ACV-12DCV 20A converter going to a 9-60DCV 20A PWM motor ...
0
votes
2answers
62 views
Is there a reason why lower voltage batteries are preferred for high AH?
I was looking at these batteries and considering whether to use a 12V battery or multiple 2V batteries for backup power. In any case, I came across this battery by Exide Tech - GNB Flooded Classic H1T ...
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votes
1answer
81 views
Is it possible to patch together a DC system with these random materials? [closed]
I have a small collection of random batteries and solar panels, plus two charge controllers. I am hoping to build a system which can charge devices like phone, tablet, portable power banks, etc. (...
3
votes
4answers
697 views
12V lead acid charger with LM317 not charging
I have this circuit built and tested. I think this should work and charge the battery with 0.4A to about 13.5V.
The Problem: it doesn't charge and between U1 and U3 (Battery) is a current of about 0....
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0answers
41 views
When to monitor battery capacity
While other good answers have stated why discharging a 12V lead acid battery is hurtful to it, I seem to be unable to find how you should monitor it.
Assuming I want to stop drawing current from the ...
0
votes
1answer
44 views
Controlling 12V 70A Motor(s) with Arduino MEGA (or NANO) and a 4-terminal automotive relay
Components I have:
Relay (rated at 12V, 70A, cannot find how much current is needed to saturate its coils) Schematic
Arduino MEGA and NANO
12V Powerwheels battery + AA battery packs
Motor: 00968-...
0
votes
1answer
40 views
Normally Closed Negative Output, Positive Input Relay
I'm attempting to wire up my remote start in my manual transmission vehicle to ONLY start when the vehicle is in neutral. The way that the transmission works is like this:
When in neutral, resistance ...
0
votes
3answers
86 views
What is this small circuit board used for in a 12v light?
Repairing a home-made disco light that was used in a nightclub during the 80's/90's and it consisted of 16 12v 50w lamps arranged on 8 legs.
I have discovered a small circuit board within each lamp ...
0
votes
1answer
91 views
How to check (6 pin) PCI-E power rail on a pc powersupply?
Could anyone tell me if and how i might verify whether or not a PCI-Express 6 pin power lead on a PC is outputting correct voltage(s) ?
A while back, I decided to try to refurbish a graphics card ...
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3answers
74 views
Using 220V wiring for a 12V setup
I am living in a static house that uses a 220V system for lighting fridge etc, I wish to set my solar system up using 12V not 220, I have a gas fridge and don't need 220V, I will only have 7 LED ...
0
votes
1answer
64 views
12V - How to activate an electric item if battery is full
I have a solar system 12V connected to a PWM controller 20A and a lead-acid battery 80Ah deep cycle.
What kind of setup should I make to activate a pump (12V) if the battery is full ( >13.8V ) ?
0
votes
1answer
30 views
Two power sources into appliance (12Vdc)
I am creating powering board for LED strips inside the cacti glass house. It consume 12V DC around 2 amps. I would like to power them up from battery (charged by solar, lead-acid battery 20Ah), but if ...
0
votes
3answers
83 views
micro-switch 12V DC use in vehicle?
Using 12V DC (max 3 amp) linear actuator in a standard car,
I need to use some micro-switches in the power circuit to prevent the actuator powering, if it's not in the correct position i.e. won't ...
0
votes
1answer
30 views
24V 3D Printer - power ratings
I have a 3D printer at home and looking to improve some parts.
The PSU on the printer has no labels so I'm not certain what it's doing - but the 3D printer's spec. sheet says it's 600W peak and it ...
0
votes
2answers
94 views
Raspberry Pi Zero 12V Battery backup to 5V - do I need the resistor?
I found this diagram on the internet which seems to divide the voltage down to 5V and still be able to deliver 1A with the 7805 just like I want.
It will use a 12V lead acid battery and a 12V IN ...
0
votes
3answers
150 views
12VDC to 3 Phase 400V
In order top prevent my seldom used deep well pump (3 Phase, 400V) I plan to daily spin it up for a few seconds.
Where the pump is located, the is no power supply (I operate the pump using a ...
0
votes
1answer
108 views
Need to determine a mosfet, and wouldn’t mind a little education in the process
I want to start off by saying that I am a complete electronics newb. I know a little but am always looking to learn more. With that said I am asking for a little help and a little learning.
Here’s ...
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0answers
54 views
12VDC Switching to 17VDC high amerage
It's been years since my undergrad work as an EE. I am a physicist and medical researcher now, but, as a startup, we all take on anything we can.
Let's face it... 12VDC high current PSU's are cheap. ...
0
votes
1answer
27 views
BMS for 2S Lipos
I have 2 lipo batteries in series, each has a built in protection circuit and these specifications:
Voltage: 3.7 Vcc
Capacity: 1000 mAh
Maximum discharge rate: 2100 mA
I need to charge them, but I ...
0
votes
1answer
51 views
Power inverter - what component blew
I have a new 2 kW inverter connected to my 12 V lessure battery. As soon as I had plugged a 1 kW appliance into it it blew. Pic shows a component that looks like it's melted. I'm very limited with ...
0
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1answer
63 views
What is the cost of converting 12V (lead acid battery) to 220V and back again to power 12V appliances?
I have a small house measuring ~ 8m x 4.5m. It is in Indonesia and power outages are expected daily. Probably the daily power outage is on average less than half-an-hour, but sometimes the outage can ...
3
votes
4answers
132 views
Motorbike turn-signal blinker starts OFF, I want it start ON
I bought a cheap blinker that claims to be good for LED bulbs (so the frequency is independent of the load.)
It is true, but it has a flaw: the lamps go ON only after about a half second from when I ...
0
votes
1answer
50 views
Using a Computer PSU for its 12V output for high wattage loads [closed]
I'm looking to install some LED light bars (primarily designed for use on off-road cars) as fixed outdoor lighting on my property. I see they have models that use up to 700+ watts of power (for crazy ...
0
votes
0answers
30 views
TPS55165Q1 does not work in boost mode
I need a power supply that delivers 12v with an input between 8v and 35v. That's the reason I bought a couple of TPS55165Q1 from Texas instruments. I've made 3 different PCBs with a similar circuit. ...
0
votes
2answers
93 views
Will a 4 Ah 12 V battery be fine for a 2 A 12 V diaphragm pump + a Raspberry Pi?
I've got a 4 Ah 12 V lead acid battery which currently runs a Raspberry PI. I'd like to connect a diaphragm pump to this battery as well. The pump has a max. rating of 2 A.
Assuming a fully charged ...
0
votes
1answer
101 views
Solar charge set up damaging battery?
I've installed a 12V 80W solar panel plus controller and attached it to a 12V 105Ah leisure battery. At first it (appeared to?) work. The charge status on the solar charge controller was at max and it ...
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vote
2answers
647 views
What is the lowest voltage a 12V lead-acid battery in a car could be?
I'm trying to design a product that is powered from the 12V rail inside the car. In normal driving (engine running, electronics on etc.), what would be the minimum voltage of a low battery?
Reading ...
0
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2answers
58 views
How can I get this 12v motor to run smoothly, and is it set up safely?
This is my first attempt at electrical engineering, so I'm sorry if this question seems basic, I couldn't seem to find answers anywhere.
I want to wire a 12v motor to an on/off switch and power with ...
1
vote
1answer
191 views
12v DC brushless PWM fan burnt out via Arduino Uno
I’m working on a project where I want to control the speed of a fan using a microprocessor.
I read several posts about using an Arduino Uno to control the PWM function on a 4 pin fan you find in PCs, ...
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votes
2answers
89 views
Limiting current to a LiPo battery [closed]
(Updated: Amended text. The smaller battery is a lower voltage than I originally thought.)
I have a small 7.5V LiPo battery that needs a top-up charge of max (say) 500mA from a large 12V LiPo battery....
0
votes
6answers
218 views
AND gate - 4 inputs, 12V
I want to make multiple AND gate input device.
I have 4 locks (3 wires each; common, lock and unlock state) I want to monitor those states from locks and connect them to inputs (IC inputs) so when I ...
0
votes
0answers
70 views
How can I achieve 5V DC from 230V AC wirelessly? [duplicate]
I want to step down 230VAC so that I can have a large amount of current that I can transmit wirelessly through the transmitter coil to the receiver coil.
I want to transmit it across 5millimetres ...
3
votes
0answers
117 views
How can i transfer 12 V, 50 Hz, 1 A wirelessly? [closed]
I want to transfer electical power wirelessly from a transmitter to a receiver coil.
Input energy is provided by a single phase step-down transformer - 230V/12V AC, 50 Hz, 1,000 mA.
Using the 12 V ...
