Search found 1345 matches

Tue Nov 26, 2019 8:57 pm
Forum: Beginners
Topic: GPIO dry contact output Python progamming help?
Replies: 4
Views: 129

Re: GPIO dry contact output Python progamming help?

1 Size of motor Voltage Amps( hp) DC or AC
2 Voltage and current rating of the relay
3 Your program must be fail to safe

Regards BoyOh
Fri Nov 22, 2019 11:08 pm
Forum: Beginners
Topic: Measuring frequency in a voltage signal
Replies: 11
Views: 334

Re: Measuring frequency in a voltage signal

trejan wrote:
Fri Nov 22, 2019 5:03 pm
How high is high frequency?
Time applied to a repetitive action ( Frequency)
BoyOh
Fri Nov 22, 2019 4:22 pm
Forum: Beginners
Topic: Measuring frequency in a voltage signal
Replies: 11
Views: 334

Re: Measuring frequency in a voltage signal

hitsware wrote:
Thu Nov 21, 2019 2:52 pm
Say you covert to pulses and connect to gpio pin .
What then to count ?
I think a little understanding of Digital Electronics
Might be of help to you on how to use the Pi as
a counter.
Regards BoyOh
Thu Nov 21, 2019 11:30 am
Forum: Beginners
Topic: Measuring frequency in a voltage signal
Replies: 11
Views: 334

Re: Measuring frequency in a voltage signal

This is only a wild Idea to count the peaks is
Use a Zener diode as a peak clipper, At this point
The Zener diode will conduct .When it conducts
Use a Opto Isolato to switch a signal to the
Pi input

Regards BoyOh
Wed Nov 20, 2019 11:05 pm
Forum: Beginners
Topic: high speed counter
Replies: 10
Views: 235

Re: high speed counter

You have got me beat, what is a bubble counter. What is the method you are using
To get your pulse in to the counter, the counter is no problem as long as it will get a pulse

Regards BoyOh
Sat Nov 16, 2019 8:57 pm
Forum: Beginners
Topic: If I buy RASPBERRY PI 4 Model B - Kit 2 GB, is that all I need?
Replies: 26
Views: 727

Re: If I buy RASPBERRY PI 4 Model B - Kit 2 GB, is that all I need?

This is one of main points that is not emphasised By the Raspberry Pi , It is not PLUG & PLAY A very basic understanding of electronics is Very useful when using the Pi, You will have A better understanding of it’s power requirements IT is like buying a car when you can’t drive, Learn to drive first...
Sun Nov 10, 2019 12:23 am
Forum: Beginners
Topic: Rpi4 questions about power supplies and performance for a media server and home automation hub
Replies: 3
Views: 170

Re: Rpi4 questions about power supplies and performance for a media server and home automation hub

First get a understanding of basic electronics
And power supplies, There are lots of books on
Power supplies. You seem to know what you
Want, put unable to put it in to practice
Break your projects down, pick the simplest
Fist and see if you can complete that first

Regards BoyOh
Mon Nov 04, 2019 4:06 pm
Forum: Beginners
Topic: Use a raspberry Pi with Relay, Photocell, and Momentary switch to control Powder Trickler
Replies: 9
Views: 605

Re: Use a raspberry Pi with Relay, Photocell, and Momentary switch to control Powder Trickler

Amazing stuff, flour. Many years ago as a student I spent a couple of summers cleaning a mill on Birkenhead docks. Its explosive capabilities are rather over-rated - why else would the Chinese have invented gunpowder? (likewise diesel, compared to petrol - which would you rather throw a lighted mat...
Sat Nov 02, 2019 11:53 pm
Forum: Beginners
Topic: DIY Scalable Door Access System
Replies: 3
Views: 437

Re: DIY Scalable Door Access System

My apology, i should have introduce my background a little bit. I have experience in PLC programming with Allen-bradley and Siemens, meaning I know all the basic in connecting switches and sensors. Also since I work with a System integrator, I have some experience with modbus serial communication. ...
Sat Nov 02, 2019 3:01 pm
Forum: Beginners
Topic: Virtual Pi development
Replies: 8
Views: 512

Re: Virtual Pi development

I've been looking for a free Pi 3 B+ emulator I could use to code and test virtually but I'm getting very confused on what's available and whether it's even possible. I saw a similar question posted by ptimlin in Jan 2019 but appears the answer to that was No - but I'm not sure. I also saw that Pro...
Fri Nov 01, 2019 9:48 am
Forum: Beginners
Topic: DIY Scalable Door Access System
Replies: 3
Views: 437

Re: DIY Scalable Door Access System

This is a very ambitious project for a novice With no electronics experience, All the safety Problems you will encounter will have to be dealt with, Personnel fire risk, due to system failure I dought that your Insurance will cover a home Made system, Writing and talking about it, is Totally differe...
Thu Oct 31, 2019 3:04 pm
Forum: Beginners
Topic: Path to pressure sensors
Replies: 4
Views: 307

Re: Path to pressure sensors

It is how to incorporate them in to a circuit
Is the main thing, More research in to your
Project is what you need, And some breadboard
Work on the use of sensors, and how to interface
Them with the Pi, The Pi is not plug and play’

Regards BoyOh
Thu Oct 31, 2019 2:41 pm
Forum: Beginners
Topic: Pulsing LED
Replies: 8
Views: 431

Re: Pulsing LED

Opening and closing the valve have nothing to do with the signal lines. There are 2 more lines to the valve carrying 24V that are used to open and close the valve. Also the valve stays in its open or closed state no matter what happens to the power. It is a ball valve not a solenoid. That is the pr...
Thu Oct 31, 2019 12:11 am
Forum: Beginners
Topic: Pulsing LED
Replies: 8
Views: 431

Re: Pulsing LED

Don’t wire the valve switch in the program loop
Keep it just to indicate valve open or closed
The valve will close with power failure , but will
Indicate position when power back on..
You will have to include the valve will only
Open if the program is running

Regards BoyOh
Wed Oct 30, 2019 11:11 pm
Forum: Beginners
Topic: Use a raspberry Pi with Relay, Photocell, and Momentary switch to control Powder Trickler
Replies: 9
Views: 605

Re: Use a raspberry Pi with Relay, Photocell, and Momentary switch to control Powder Trickler

I planned to use Salt until I get it all worked out. Agree on the breadboard. Salt is a much better idea. Flour and air can be a very explosive mixture. I picked flour it was the first thing that come in to my mind. As the most important thing on my mind Was the flow of Electrons in the project? Re...
Tue Oct 29, 2019 10:55 pm
Forum: Beginners
Topic: Use a raspberry Pi with Relay, Photocell, and Momentary switch to control Powder Trickler
Replies: 9
Views: 605

Re: Use a raspberry Pi with Relay, Photocell, and Momentary switch to control Powder Trickler

You could use a slotted Opto Isolator as the As the scale switch, It can be easily mounted And made adjustable., The opto isolator Transistor can be used as a buffer stage To control a solid state relay and other Electronics on this project Set it all up on a breadboard, It will give you Some experi...
Sat Oct 26, 2019 12:05 pm
Forum: Beginners
Topic: New to Pi, question about a project (Want to add LEDs to a map )
Replies: 7
Views: 419

Re: New to Pi, question about a project (Want to add LEDs to a map )

Is there a possibility of using Optic Fibres to Project the points on the weather map. Then Having the Tri colourer high bright LEDs Mounted on a rack with the Optic Fibres The LEDS could be very small, All the wiring Could be done on the rack. That would cover The hardware side. Then to design the ...
Tue Oct 22, 2019 10:24 pm
Forum: Beginners
Topic: Which Pi for a beginner?
Replies: 9
Views: 646

Re: Which Pi for a beginner?

My advice is get the latest model Pi that is out A high power Pi will do all the low power projects With ease, Ware as you will be restricted power Wise with the low power Pi Remember the same Laws applies to both ( OHMS LAW) The same applie When picking a power supply . A high out/put Power supply ...
Sat Oct 19, 2019 10:41 pm
Forum: Beginners
Topic: Regarding the current measurement
Replies: 23
Views: 1516

Re: Regarding the current measurement

It might be possible to fit a 10ohm resistor In series with the main 5v in/put lead to the Pi, then using a multimeter to read the voltage Drop. Then using the difference between the readings to calculate the current when the code Is active. Might be worth a try use a high wattage Resistor Regards B...
Tue Oct 15, 2019 11:19 am
Forum: Beginners
Topic: Raspberry pi 4 and fan
Replies: 9
Views: 922

Re: Raspberry pi 4 and fan

If you use the Pi as it should be used, you don’t Need extra heat sinks or fans, Just use the Pi Low current to switch transistors and Opto isolators as buffer stages Such as voltage Levelling and current amplifying from a separate Power supply to run your project Regards BoyOh We need 1.5GHz and 4...
Mon Oct 14, 2019 11:14 pm
Forum: Beginners
Topic: Raspberry pi 4 and fan
Replies: 9
Views: 922

Re: Raspberry pi 4 and fan

If you use the Pi as it should be used, you don’t
Need extra heat sinks or fans, Just use the Pi
Low current to switch transistors and
Opto isolators as buffer stages Such as voltage
Levelling and current amplifying from a separate
Power supply to run your project

Regards BoyOh
Sun Oct 13, 2019 9:55 am
Forum: Beginners
Topic: A relay turns a light on/off, how to detect a burnt light ? [solved]
Replies: 40
Views: 1746

Re: A relay turns a light on/off, how to detect a burnt light ?

You are using the forum to do the research for you
I hope you will donate your fee to charity, You should
Have said in the first place you are doing it for a
Re-seller, be fair give us the name of the re-seller
You are working for, so we can tell them It is not.
Regards BoyOh
Sat Oct 12, 2019 3:56 pm
Forum: Beginners
Topic: A relay turns a light on/off, how to detect a burnt light ? [solved]
Replies: 40
Views: 1746

Re: A relay turns a light on/off, how to detect a burnt light ?

This project as a lot of draw backs to Compleat Due to the different types of lamps in use I think light detections is the best ( LDR) Current and voltage sensing might not be the Answerer due to some lights employ ballast Units and different controls , the current Could still be flowing, but the la...
Wed Oct 09, 2019 10:55 pm
Forum: Beginners
Topic: Components and Pins
Replies: 14
Views: 700

Re: Components and Pins

If you are having difficulty understanding
The layout of the breadboard, use it as part
Of your learning curve . Using a multimeter
Set to continuity testing and two jumper wires
Then just use some Common Sense

Regards BoyOh
Fri Oct 04, 2019 1:06 pm
Forum: Beginners
Topic: How to control the Zener Diode.
Replies: 3
Views: 200

Re: How to control the Zener Diode.

This will give some idea how to use a Zener Diode
Do as others suggested draw a circuit diagram