A relay is an electrically controlled switch. Electromechanical relays use an electromagnet to activate mechanical contacts, solid-state relays use semiconductor switches.
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47 views
Routing Current to Many Individual Channels [duplicate]
Possible Duplicate:
How to implement an isolated connection matrix
I need to put current on up to 30 lines; one at a time. What kind of electronics solutions are there to this kind of ...
5
votes
2answers
148 views
What is the difference between VA and W for a relay
I am trying to choose a relay to control a compressor.
The compressor alimentation is 230V (50Hz), the max intensity is 0.9A and the power needed is 130W.
Then i found two relays: the ALD112W and ...
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3answers
380 views
Parallel port controls a relay
If I want to use a parallel port to control this 8 channel relay instead of Arduino, do I need to make any modifications?
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2answers
297 views
MOSFET or bipolar to drive a solenoid valve?
I have to drive a 12V solenoid valve. In the datasheet it's written: Power: 8 W. So the current drawn by the solenoid is 0.666 A.
Usually, to drive small relay (about 10 or 20 mA) I use a bipolar ...
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2answers
145 views
How to implement an isolated connection matrix
I need to implement a circuit for a researcher, which looks a little bit like this:
Description of the circuit:
There are two or more fully isolated biphasic current drivers, and N output pins. ...
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1answer
688 views
How can I activate a circuit with a remote control
I'm new at the forum, registered today.
Well, I want to make an system which can be activated by a remote control, or even by a switch.
The meaning of it all is to TURN ON something wirelessly, ...
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2answers
964 views
Using a transistor instead of a relay to control a DC motor
I've made a simple relay circuit to switch power to a small DC motor
Here is a diagram of what I got right now:
Is it possible to replicate that with a transistor. Which one would be a good choice?
...
2
votes
1answer
143 views
From a power consumption point of view, which should I use: SSR or Relay?
I'd like to find out which to use: a SSR (Solid State Relay) using TRIAC and optocoupler or a relay.
My consideration are from the point of power consumed, my challenge here is to choose the less ...
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1answer
480 views
GPIO and relay quesiton
I have a question about the YouTube video Raspberry Pi Controls Relay. It's about controlling a SainSmart 4-Channel 5V Relay Module. Is it driven directly off the 3.3V GPIO?
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5answers
257 views
Interface 5v digital pulses to keyboard contacts?
I currently have the following bit of kit: Photoplethysmographic sensor for measuring heart rate
It outputs a 5v pulse each time your heart pulses. What I need is to do is interface this pulse output ...
5
votes
2answers
967 views
Is analog SPDT IC switch same as mechanical relay?
I am working on a project which require to trigger a SPDT switch using a button to pass a small signal voltage across (~3.3V).
reference circuit image below
The requirement is:
signal must still ...
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1answer
207 views
Looking for a 24vac switch from 3v inputs
I'm really new to building electronics, so please forgive my ignorance.
I'm looking to be able to supply 24vac (~.5A) to one of 16 outputs using 4 3.3v, 50mA inputs.
(Edited) The 4 3.3v inputs are ...
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5answers
474 views
Looking for help on why my n-channel mosfet is getting destroyed
I've got a design that I've inherited with a pretty standard n-channel mosfet driving a relay that controls a motor and actuator.
On a recent build we started getting a 50% failure rate on the ...
3
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3answers
522 views
Simplifying a relay network
I'm currently trying to design a relay network for a piece of laboratory equipment (PPMS). I would like to describe what the setup is, what I am doing now, what I hope to do, and how I hope to do it. ...
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2answers
1k views
Driving a single-relay board with Raspberry Pi
I have one of these single-relay boards and I am trying to control it with my RasPi's GPIO. (I'm a complete noob).
I am using WiringPi and in this particular case I'm using pin 1 (aka BCM pin 18) as ...
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3answers
325 views
Turn on a relay when the output is high
I purchased a 5V 8 channel realy to use with Arduino.
When the output is low the relays are on. I need to turn the relays on when the output signal is high.
Is there a way to make the board respond ...
3
votes
1answer
109 views
Solid State Relay Question
The solid state relay board functions normally by shorting + to input, but latches closed on device side of the relay until load is turned off or is disconnected.
Is this normal for solid state relays ...
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1answer
56 views
Subject Selection [closed]
'Utilizing Electrical Energy' or 'Protective Relay' which subject should I choose in my 5th Sem in Electrical and Electronic Engineering. Help me giving me advice on this topic.
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1answer
202 views
What's the easiest way to create a software-controlled 220V electricity interruptor?
As the title says, I'm looking for an easy way to interrupt a 220V electrical cable and to write a software that controls the interruption.
I imagine there are some kind of relays or contactors which ...
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votes
1answer
243 views
how many light bulb for one relay?
i've just done this tutorial: http://www.arduino.cc/es_old/Tutoriales/Rele
it works great! i've done it in a breadboard (with two 5v circuits for test) and then soldered (for just does not have 220v ...
2
votes
2answers
174 views
Creepage and clearance when using relays
I'm looking at this 10A, 277VAC relay and wondering if there is sufficient spacing between the low voltage (3.5V, 100mA) and the high voltage(277VAC, 10A). The foot print looks like this:
Are the ...
6
votes
3answers
3k views
In a circuit being switched by an NPN transistor, do power supply and input need the same ground?
I'm trying to make a circuit that will allow me to switch on a relay that will turn on an LED. However, the relay is rated for 12 V, and I only have an input of 5 V, so I'm using an NPN transistor. to ...
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votes
2answers
835 views
Why did relay run when I applied half the nominal coil voltage?
I'm using a RadioShack 12V DPDT relay, model 275-249.
I applied 6 V across the coil and the switch closed. Why is this? I didn't have any resistors in series with the 6 V power supply (the only ...
5
votes
2answers
384 views
Controlling a power strip with a toggle switch. Flight sim design
I am building a cockpit. It will function basically as a flight simulator but for a different game. Mechwarrior online. a Mechpit. Here is my problem.
Toggle switch 1 when flipped on turns on the ...
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2answers
306 views
Is the garage door open? Reed relays [duplicate]
Possible Duplicate:
How can I detect if a garage door is opened or closed?
I'm planning to make something to detect if our garage doors are opened or closed. We have a server where I'm ...
3
votes
3answers
882 views
Shift Register output to Relays
sorry for the length.
This is a continuation of my recent question. I have an optocoupled 8-relay board that I’m trying to connect to my microcontroller. I have placed a 74HC595 shift register inline ...
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2answers
159 views
Possible Relay Overload
I'm currently using the following opto-isolated relay board: URL
Everything is working correctly, I can switch on and off a small light without any problems. Now as soon as I plug in a larger load ...
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2answers
142 views
Different design in relay load connections
(I know, relay are drawn in the wrong way, NO contacts should be in serie with load, I'll fix it ASAP)
When I have to build a board to switch many devices (mains powered), I always use a single ...
3
votes
2answers
3k views
Selecting the right relay
I'm looking for some advice on what type of relay I should use for my circuit.
I have a 5v power supply and I want it to act just like a switch. I will be controlling it with an Arduino like ...
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votes
2answers
1k views
GPIO remote switching PC on/off
I saw a post on raspberry official forum. It's about GPIO remote switching PC on/off, but it is not very detailed. I am pretty interested in it and i have this relay. I am wondering if anyone here has ...
3
votes
3answers
1k views
BJT, resistor, and diode work but ULN2803 does not
I am trying to control some 5V relays with a mC. At first I went with using a BJT, a 470 ohm resistor, and a 1N4004 diode to control each one of the relays. Each mC output pin is 5V, 40ma. This ...
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2answers
192 views
Relay power supply
The reason I am writing is I was curious about hooking up a higher external power supply, Can I hook up a 120v to the 4channel 5v relay module? or does it have to be 5v. I am trying to only use my ...
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votes
1answer
88 views
Relay current question
For the 16 CH 12V Relay module, does the output currency mean that we could run 5VDC, 12VDC or 24VDC through the relay? What ever current we input will be the output current, correct?
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2answers
855 views
relay connection, how?
I got this on hand http://www.sainsmart.com/arduino-pro-mini.html, how can i connect my Arduino Uno to control it?
Can someone help with an example connection provided to the Arduino side to control ...
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vote
2answers
672 views
8 channel 5v relay
I bought an 8 channel dc 5v relay module for Arduino from an on-line store. When i power on my system, the modules become really hot.
My connections are,
Vcc to 24vdc
Gnd to ground
In(1-8) to the ...
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votes
1answer
663 views
Sainsmart relay output wiring
I have a 2 Relay module from Sainsmart. http://www.sainsmart.com/arduino-pro-mini.html/
The output has 3 connections instead of just 2. I want to know which two of these three connections I need to ...
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vote
2answers
174 views
Using relay to control
Using a relay, if I found a 12v source on the ps3 motherboard that was on only when the ps3 was on. Could I attach a 12v relay switch to it and the connect some LEDs that run off another power supply ...
4
votes
2answers
1k views
Driving Solenoids from Arduino
I was wondering what the best way to run a solenoid would be from an Arduino board. I was thinking about using a MOSFET that runs into a relay to turn on the solenoid but am not sure how to go about ...
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votes
1answer
415 views
How to connect a SPCO relay?
I have a relay SRM-1C-SL-5VDC. I am trying to switch the load On/Off using this relay. I am not sure how to connect it correctly as there its not mentioned clearly in the datasheet. Which pin on the ...
5
votes
2answers
641 views
Flyback diodes issues and pull-in & hold current issues in this Relay circuit
Although this may be a basic question but I'm still struggling with it. In this schematic, two zener diodes D1 and D2 are connected back-to back across relay coil L1. The BVds = -30V for Q1. Can I use ...
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votes
1answer
150 views
Motor Protection
I am having a control panel to operate a green house fan and pad lab.
in this lab i am having,
2 fans
1 temperature sensor(PT-100)
1 humidity sensor
1 motor for water flow(2 HP)
1 motor for fogger ...
18
votes
5answers
2k views
What are some ways to use relays more efficiently?
We often seem to use microcontrollers to control relays, and a 5 V microcontroller is often used with 12 V relays. A relay may need several times more power than the microcontroller. Not a problem if ...
3
votes
4answers
3k views
Optocoupler/relay type for isolating two DC circuits
I have recently started experimenting with an Arduino and would like to control a seperate circuit (for example, a small and cheap digital video camera powered by battery) from my arduino.
Basically ...
5
votes
4answers
360 views
Understanding of Relays and associated circuitry
I needed a simple understanding of how this circuit works.
I understand everything about this circuit apart from the diode. I also know the function of the diode is to protect the transistor but ...
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4answers
577 views
Alternatives to transistors
I'm trying to think of alternatives to transistors, simply because I'm curious. I don't care so much about the amplifying characteristics of transistors as their ability to make logic gates. Here's ...
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2answers
333 views
Will this circuit work containing 2 transistors?
My gran keeps turning her internal light on in the car and then forgets to turn it off again. She has flattened the battery 5 times in the last few months.
I've been looking at how integrated ...
4
votes
3answers
663 views
Help with a simple comparator circuit
I'm trying to build a simple temperature controller by using a thermistor and a potentiometer attached to a Schmidt trigger to control a relay.
I realize that I have some serious design flaws in ...
5
votes
5answers
4k views
Simple and safe solution to control a power plug with Arduino or PC
What solutions are available to control a power plug (or even if possible a light socket), i.e. turning it On and Off?
I have looked for xbee/zigbee solutions but there doesn't seem to be a solution ...
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2answers
2k views
Choosing a relay to control outlets from Arduino
I'm working on a project that involves an Arduino Uno and some external electronics. I have a 12 V power supply that will connect to an outlet, and I want to be able to control this power using a ...
0
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2answers
175 views
AC control coil relay
Is there a type of relay where the control coil can operate from a 220/240 VAC signal? I don't want to convert my existing signal from AC to DC. Are there any special search techniques to find parts ...
