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Questions tagged [amperage]

Amperage is the strength of an electric current in Amperes (Sometimes shortened to Amps).

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2answers
81 views

Why is my Transformer pulling so much current?

I have taken a microwave oven transformer and removed the 2nd winding which originally put out 2000 volts. I have rewound the 2nd coil to produce 21 VAC which I then rectify and smooth with 2 large ...
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4answers
100 views

Are amps provided or drawn?

I am trying to understand how amps work exactly. I see variations of the following in various online sources. From here: [...] A standard household circuit that supplies your outlets and switches ...
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1answer
42 views

Transformer vs. switched-mode power supply

I'm working on making my own bench power supply, I want up to 7-8 amps. The switched mode power supplies are much cheaper than the transformers. Why would one choose a transformer instead of switched ...
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0answers
32 views

Can I force my battery pack to output specific amounts out of each port? [closed]

Let me explain, as I wasn't sure how to phrase it concisely in one question. I've got a portable battery charger, this one specifically, and I am attempting to power 2 devices from it. One of them ...
6
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1answer
115 views

Can I decrease voltage to get higher amperage?

If I have for example a battery that outputs 10 V but with a maximum of 0.5 A. If I took the output of the battery and entered it in a buck converter to get 5 V will I get the same 0.5 A at 5 V or I ...
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2answers
57 views

Why is voltage specification irrelevant in tripping a PPTC polyswitch?

In a circuit, a resettable fuse (or polyswitch or PPTC) is a kind of breaker component that trips when the AMPERAGE exceeds a given treshold to protect against overcurrent faults. PPTC basically ...
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0answers
55 views

Problem calculating fuses

I am calculating a fuse and I'm having a bit of trouble. I have a 12v 2A power supply that I want to protect, so my first thought was to place a fast 250v 2.5A fuse in series so it should blow if a ...
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2answers
77 views

why volt is needed for calculate watt? [closed]

hello i dont sure what is the difference between voltage ampere and watts. voltage is only the potential difference between points high voltage will not cause to the electrons to move faster so why ...
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1answer
46 views

Problem Powering 13.3 inch LCD Screen with 3.7v Battery [closed]

I have been working on a project that involves running a 13.3 inch lcd screen off of a rechargeable battery. I bought the lcd screen and controller board listed below and verified that it was working ...
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8answers
3k views

What is negative current?

I understand that voltage is relative to ground, so that can be negative. However, I'm currently looking at current-sensors (ACS712 current sensor) and in the performance characteristics table, it ...
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2answers
138 views

Why does the measured current differ from the calculated current in this circuit?

I have the following schematic: Now I want to know the (more or less) exact current flow in my circuit. For this I did the following calculations: I = V / R I = 5V / 330 Ohm I = 0.015A = 15mA So ...
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2answers
87 views

Unexplained amperage spikes

IT guy here - I have a device called a WattBox in one of my networks so I can remotely cycle power on an outlet. It also provides me with alerts when something falls outside set parameters. I've ...
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1answer
72 views

At what point a battery becomes a load

This has probably been asked before but I don't know how to search for it. In a circuit where there are a battery and a variable power supply, what conditions have to be met in order for the battery ...
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3answers
93 views

240 volts circuit amp

Basic question, but I have a doubt! I have a pool heater that works from 240 volts. In order to calculate the annual operating cost, I installed a device that measures amperage and adds up the total ...
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2answers
42 views

Hedge relay current capacity with additional wiring

I ordered several OMRON “ice cube” 110 VAC relays, contacts rated for 10A (LY2NJ). When I inspected them under a microscope I noticed the contact wires are AWG 24. The rest of my setup uses AWG 18. My ...
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1answer
123 views

Building a Huge 18650 Battery Powerbank DIY [closed]

I know there are a lot of threads about this topic already, but I still have some questions about it. Anyways, I am thinking about making a 50-80 thousand mAh power bank depending on the batteries and ...
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0answers
67 views

Lower amps than expected?

I build an inverter to power some panels of EL paint (If you don't know what EL paint is check out this link). It puts out some very high voltage and I thought I'd check to see what amperage it is ...
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1answer
102 views

How to reduce 30 amps to 5 [duplicate]

I recently bought a Transformer so that I can make an ionic lifter but it has a max 30 amp output and I’m sure that is way too much for what I need plus Since I have this plugged straight into the ...
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1answer
50 views

How many amperes can pass through drain-source of a FQPF9N50C if 3.3v are applied to gate-source?

I a playing around with this N-channel mosfet I found at home (FQPF9N50C). Using this simple circuit: I am able to turn on an off the 12v load using by connecting 3.3v to the mosfet. The load is a ...
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2answers
64 views

How to determine cross section of cable [duplicate]

I'm looking at this table that suggests a 0.5mm2 cable could withstand 720W at 3A. At the same time I used a cable size calculator online to determine the size of cable I would need to use for a ...
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2answers
67 views

What's the suitable wire size for 9VDC @25 Amps line?

I am trying to put together the requirements for a cable and I was wondering what would be the most suitable wire size to load the DUT with 25Amps @ 9VDC. I will have few other high current lines ...
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1answer
94 views

Multimeter seems to be giving incorrect mA reading [closed]

I'm measuring the current drawn from the negative battery terminal of my car battery. I am not sure if the correct reading is 0.16 A or 1.6 mA. I tested with my multimeter on both 10 A and mA ...
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2answers
86 views

Stacking M.O.T. to create an E-E core

I just came across this site looking for answers on some questions I have concerning microwave oven transformers (M.O.T.). I am currently going into my third year as an E.E. student and I am trying to ...
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3answers
64 views

What connectors should I use with 5V DC current?

In a personal project, I need to power several 5V appliances which, together, use up to 12A. I want to use a 60 inch cable between a case to which those appliances are connected, and the transformer ...
1
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1answer
45 views

Wheelchair battery life calculation

Apologies because I'm sure this is an incredibly basic question and I've tried to work out the answer myself but I'm getting nowhere with it! I'm looking to get a powered trike attachment from my ...
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1answer
49 views

Have I burned out my HD motor? [closed]

I accidentally cross connected my external HD and my computer power cables. Only noticed it when my computer complained it was not charging. MY HDD is no working but I have had problems with it ...
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2answers
88 views

Advice for using 60 watt peltiers? Is 12V 3A enough to get the job done?

The weather right now is so bad and hot! A friend of mine runs a mobile stream and his phone refuses to charge when it is hot. His stream crashes because he can't charge his phone or it overheats. Not ...
1
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0answers
112 views

Why are all my motors and transformers failing at this specific location?

At my job there is a vacuum oven. There is a 50 hp, enclosed cooling fan. that circulates N2 gas upon quench, the design of the unit runs 480 volts through a reduction transformer to 230 volts. This ...
2
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2answers
57 views

Why can a charger handle more watts at a higher voltage?

Why is it that my charger that has a rating of 100-240 volts and 1.3 amps can handle/input more watts at a higher voltage when doing the formula watts=volts x amps? In addition, why can't it, at a ...
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1answer
59 views

Integrated circuit which acts as a switch

I have the following problem. I have an electronic door lock with opens the door whenever it is feeded with 12v (tested and it works perfectly). My main issue is that the signal for opening the door ...
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1answer
122 views

How do I reduce amps in a DC circuit? [duplicate]

I'm trying to replace my AC adapter with a battery. The AC adapter output is 12v @ 500mA DC. I can get a 12v battery, but I can't find one that outputs exactly 500mA. I'm trying to power a strip of ...
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4answers
89 views

Solar cell outputs full voltage but barely any amps

So I've asked a similar question in the past, but I'm still curious about something. On a fully sunny day, the solar panel tops out at 5.5v @ 260 mA. On overcast or cloudy days, the voltage stays ...
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1answer
53 views

Can I use a 24V 1A AC/DC adapter on a 9V 2A device? If so, are there negative effects of doing this? [duplicate]

I have a gaming chair with a speaker built into it and I lost the cord for it. I managed to find an old xbox 360 cord that fit it but it’s 24V. The chair turns on with the 24V cord but I’m trying to ...
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0answers
62 views

Reducing Current?

Having a problem with my EV a converted Fiat 500. The conversion is made with part from companies that dont exist any more, so it is hard to get information about them. The car have two batterybanks ...
0
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1answer
54 views

guesstimate max current of a domestic appliance

The appliance is a quartz oven, 1000W @ 250V. I am trying to obtain a max transient figure for the current (no oscilloscope on my bench). Opened the oven and checked the writings on various parts - ...
0
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1answer
57 views

USB Port Amperage

So I have built a Benchtop Power Supply out of an old computer power supply to power and test misc. gadgets I have created. I would like to attach 2 salvaged USB ports from a junked computer to the 5v ...
1
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0answers
38 views

does a higher amperage source help prevent voltage sag?

I'm currently troubleshooting my car's ongoing electrical issues and during the troubleshooting process so far I have gone through multiple OEM alternators and multiple OEM & non-OEM batteries. ...
0
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2answers
45 views

do the voltage and amperage applied to a motor matter as long as the wattage stays at what its rated for?

I have an electric 180w motor from an electric go cart which currently runs on lead acid batteries but I want to convert it to have a 18650 battery pack for a power supply but I cant find the rated ...
0
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0answers
37 views

Charging Phone with a Modified Power Supply [duplicate]

I have converted a computer power supply into bench top power supply and I am now ready to add some USB ports to charge various devices. On the power supply label it shows the 5v rail is capable of ...
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1answer
52 views

How to lower amperage? [duplicate]

I have a power source that gives 5V DC and 700mA. I need to power a ventilator that requires 5V DC and 500mA ± 10%. What is the best way to lower the amperage, would a 10Ω resistor do the trick or ...
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2answers
109 views

What amp rating of 24vac transformer for LM317T

I am trying to post a new question about the lm317 to-220. I just want to know what size transformer for lm317 at full 30vdc. I know its a 24vac center tapped transformer but is it 1 amp or 5 amp ...
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2answers
177 views

9V battery to 850mA [duplicate]

I am new to electronics and trying to produce 850mA out of a 9V battery. I am just wondering if this would be possible and if so, how to do it.
0
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1answer
202 views

Does wiring 18650 batteries in parallel and/or series increase the discharge rate of the whole pack?

I cannot seem to find a solid conclusive answer anywhere on this, but if I build a pack of 6 18650 batteries in parallel which are 3500 mAh each, that would make the pack 21 Ah in total. Then I take ...
0
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1answer
40 views

Batteries Spike in Watts and Amps Pulled with less than 50% Life

To give a background on this, I have been running tests to determine the actual lifespan of a 3 cell pack of some Samsung 18650s and Tesla 2170s at just above freezing. The Samsungs are INR18650-35E ...
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1answer
88 views

How to select current for power supply? [duplicate]

I've two step motors with 12V-0.4A each, A4988 as stepper motor driver and CNC shield on Arduino. As I know I should use at least 2x voltage for stepper motors and I would like to know, if I use 24V-4....
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3answers
112 views

Maximum safe amperage for LED Strips

A lot of online resources never question the use of high amperage power supplies for powering LED Strips. As an example, 5 meters of low density (30 LEDs per m) WS2812B strips already use ...
1
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1answer
276 views

Understanding 5V to 1.8V UART level-shifting circuit

Hopefully it's OK to ask very basic electronics questions here. I had a TTL 5V UART cable, however the board I had only accepts 1.8V max. So I found some online schematics that uses resistors and a ...
0
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1answer
88 views

Ammeter scale, not sure what my amp reading is

I have a basic multi-meter that I am using to measure amp on a load. I am trying to figure out how much amps my small entertainment system draws. (LCD TV, PC, speakers.) I want to build a small DC ...
0
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2answers
78 views

Can I use this relay?

I got this relay. In the product description they say: "belastet bis zu 10 Amp/250 VAC, 5 Amp 30 VDC." which means: "charged up to 10 amp / 250 VAC, 30 VDC 5 Amp". On the relay it is printed: 10A/...
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3answers
42 views

Predictions based on resistance measurements not matching reality?

I'm using my multimeter to measure the resistance of my tongue, and leaving it on there for a full minute it seems to average out at around 1.5 Million Ohms. However, when I put a 9 volt battery on ...