All Questions
15 questions
1
vote
0
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76
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18650 capacity tester opamp voltages on inputs different
I assembled an 18650 Li-Ion capacity tester with an Arduino Pro Mini.
Here is the schematic:
When I set the discharging current to 100 mA in the code (which means there has to be 100mV on pin 3 of ...
- 21
0
votes
1
answer
304
views
Three Phase Transformer Design
I design single phase transformers, around 400W - 8000W, but now im lost because i have to design a three phase transformer ( delta - delta connection ).
I searched, trying to find a page that can ...
- 155
2
votes
3
answers
466
views
Can we connect multiple devices to the mains with just 1 cable?
The project: An Arduino DIY Relay-controlled aquarium with a water pump, a heater, and a light bulb. All 3 have the exact same wires according to the EU standards: 1 "hot" brown wire and a ...
- 411
2
votes
3
answers
1k
views
How to measure voltage of a system with a different GND reference?
I want to measure and log the voltage of a "closed" system shown in the following schematic on the left side. This system has its own reference to GND which is not connected to the ...
- 175
0
votes
1
answer
80
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I need help with putting together a battery
I want to make a 14V, 5A battery out of DIY crystal cells. Each cell is about 1.5V and 0.3A
I know I can connect on series until I get my desired voltage, but I need to increase the amps.
Is there a ...
1
vote
2
answers
580
views
APA102 LED strips behaving weirdly and flickering towards the end
I am trying to make a 29 x 29 LED matrix to display animations using the APA102 (Dotstar) LEDs with an Arduino MKR Vidor 4000 as a microcontroller. I have connected the data and clock signals of the ...
- 11
0
votes
1
answer
56
views
Replace UR battery by IMR with lower mAh [closed]
I am replacing a shaver’s battery, a Braun Silk Epil 5.
It uses a Li-Ion battery manufactured by Sanyo for Braun.
According to my research it must be a UR Battery like the UR18500L :
...
- 11
1
vote
1
answer
384
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Building a DIY projector. LED driver voltage output 24-36V, 100 watt LED voltage 32-38V. The LED driver is short 2 volts, would this matter much?
I'm in the process of putting all these pieces together to build a DIY projector.
Lens
LCD+Board
Fresnel
Condenser lens
LED
The only part I'm missing in this build is a compatible power supply unit ...
- 11
0
votes
3
answers
884
views
Is it safe to touch 8 volts?
Let me say first that i'm a noob in electricity.
I measured the voltage from my diy microwave-transformer-welder and it was 8.
I have no idea how much amps run through it but the fact that it creates ...
- 1
1
vote
1
answer
170
views
AUX input outputting +4v Causing reset of connected smartphone
I've added an AUX input to my Mercedes Audio 10 casette radio using an online tutorial. Essentially hooking up a 3.5mm jack direct to the output of the audio processor.
I'm familar with this ...
- 13
0
votes
3
answers
597
views
How could I make a 1kW fan heater consume less electricity? [closed]
My fan heater has only two settings, 1kW and 2kW.
But what if I wanted it to consume only 200W per hour ? Could I find a device to put in between to supply less electricity, how would I do that?
- 11
7
votes
3
answers
2k
views
Schematic for a lipo battery bleeder overcharge protector
OK, so I am building a 12v (really 11.1v) 10000mah lipo battery. I am going to use it on campouts to run things like 12v fans and car chargers and run other high-current devices that couldn't be run ...
- 71
2
votes
3
answers
4k
views
An appropriate voltage regulator / limiter for a 5V solar panel for USB charging?
I'm building a USB solar charger for my tablet, which has so far worked well.
I'm using a 5 Volt, 5 watt solar panel (same as this one), which outputs about 4.5V and 0.6A in real use when charging my ...
- 129
0
votes
1
answer
888
views
Which battery should I use to power arduino+motor shield + two motors
I am using two motors ( from old two drill machines - same kind, these are 3.6v motors ), connected to arduino + arduino motor shield seeed studio v2.
I tried to use 18v/1.2a battery that was laying ...
- 101
0
votes
2
answers
811
views
How do I get 12V 260mAh from 4x 6V 130mAh solar cell panels?
I'm trying to figure out how to build a DIY micro irrigation system for my small greenhouse. A part of that task is to figure out how I can charge 8 AA batteries using solar panels.
I've found a set ...
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