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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20 views

driver motor dc connect to arduino?

please help me make a dc motor driver with a large current (10A) with a relay that is connected to the arduino and code. by using two buttons Thank you
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15 views

rfid and arduino

I want to ask, I want to create a project using RFID barrier gate. I want the way it works when the RFID is scanned then the bar will be open 90 degrees, and after the vehicle passes through the ...
0
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0answers
39 views

On/Off things wireless and cheap [on hold]

I am not sure if this is the right section, but first let me tell you that I have almost no knowledge of electric circuits. What I want to do is to have in different part of the house something that ...
0
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2answers
66 views

Implementing Safety Shut-Off Relay In Project

I am working on a project which I have poured lots of cash into that involves water, pressure and electronics in very close proximity of each other... Lately, I have been considering adding some ...
2
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1answer
50 views

Relay/Contactor for 30A inrush, 250mA steady

I'm struggling to find any relay or contactor even close to the specs I need, and I've contacted many manufacturers. This is controlling a large contactor, so draws a 30A 24DC inrush current. It then ...
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1answer
55 views

Remote switching in rural village

How might we control a 2" valve >2000ft away in a remote village. We're thinking that we power the system with a 12 v or 24 v solar powered/ battery backup. The spot in the village with line of ...
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0answers
59 views

How to drive a 12V DC motor using a relay? [closed]

Our professor gave us an assignment- to make a circuit that drives a 12V DC motor using a 6V relay. I tried searching the internet, but I can't fully understand it. Can you show me a simple circuit ...
0
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1answer
22 views

Powering an External Phone Ringer - Straight Talk Home Service

My dad is having difficulty hearing his cordless phone ring in his shop, due to ambient noise. He has the phone connected to a Straight Talk home phone service device. So, there is no legacy analog ...
0
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2answers
43 views

How to use Lightsensor relay with 3v output

I want to find solution for one small circuit with Light sensor. I need one small light sensor to drive 3v output. The power of all the circuit must be 5v and when the light sensor is off (no ...
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1answer
62 views

How to power 3 different AC circuits without crossing them

I have 3 zones in my house with 3 24v thermostats. These thermostats tie into a zone relay that triggers a 120v line to each circulator to heat that area of the house. I need a way to have my timing ...
1
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1answer
57 views

How to wire this delay relay switch

Hello I recently bought this item at ebay and I am not sure how I should wire this. I will power it with a 9 volt battery and the relay will power a pump, this is how they at ebay show how I should ...
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0answers
62 views

Why are relays used in circuits when we have transistors? [duplicate]

Why do I find relays being used right next to transistors? What is the benefit or use of using a relay over a transistor switch?
3
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2answers
230 views

How can I model a relay in LTSpice IV?

I would like to use a 12V relay in my LTspice circuit, however there is no relay in the component list. How can I do? Relay model: SRD-12VDC-SL-C
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1answer
68 views

Simple reverse and forward controller for a 24v dc motor?

I have a project for my grand father and I would like to make a simple switch for his electric wheelchair. The controller of the wheelchair is already not working. Just a simple switching just to make ...
0
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1answer
38 views

General suggestion about how can I cancel the noise

I have designed a board and I have six relays on it, so I am scared that maybe when relays want to switch, my micro-controller (ATMEGA32) will stop working. I have used a diode and also a ferrite ...
0
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2answers
47 views

How to use 555 timers to control 2 relays [closed]

I'm looking for a way to do the following: Once triggered, the circuit will close the first relay (R1) for 10 seconds, then open then close the second relay (R2) for 10 seconds, then open have a ...
1
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1answer
50 views

125VAC relay with 230VAC

I bought a relay and until home hasn't noticed that its limited to 1A 125VAC. Then I found this datasheet which says that it can be used for 250V. I live in Europe ...
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1answer
47 views

Photocell and Relay switch not working properly

I am trying to build a simple circuit to switch on and off my garden lights according to the brightness level. More to the point, I'd like the lights to turn on when it's dark and off in the morning. ...
10
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3answers
674 views

Can a relay failure mode be like that?

I was fixing my dishwasher control board, and diagnosed a bad relay. Its coil is still within specifications, but the relay will not close its contacts. It is an easy fix ok, but my question concerns ...
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1answer
35 views

Relay Alternative

I wanted to see if I had any alternative to a relay for my project. I'm turning on a heating element that is powered from the wall: 120VAC (Max 30 Amps) Is their any alternative to a relay for this ...
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0answers
26 views

AC relay switch-off optimum phase?

I have a circuit which turns a 230V 50hz AC motor on and off by use of a relay. I've tried to arrange it so that the relay would be turned off when the current through the motor is zero. Of course, ...
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0answers
44 views

Arduino not switching relays

I have an arduin Uno R3 , I need to create some kind of home automation system for a project, the problem is that everything I connect to the pins works fine until it gets to the relays, I tried ...
4
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2answers
338 views

Verify this charging circuit

This is the circuit I have designed. I want to be sure whether I have designed it properly or not. Here is the Purpose: I am trying to power a Network device 24 hours which requires 9v (600ma). I ...
0
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0answers
10 views

Arduino Relay Shield [migrated]

I am wondering if this Arduino Relay Shield design would be good enough to handle 120v 1amp The transistor is a 2n4401. Also The Two capacitors on the other 3 circuits would be going to ground opps ...
2
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1answer
49 views

Relay EMI. Should I be worried?

I am using PCB soldered relay to switch 8-10A 220V appliance. Out of curiosity, I tried to visualize the EMI being radiated from arc sparking. I attached the GND to Neutral pole of proble and kept the ...
0
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2answers
47 views

Control 5V relay from mbed LPC1768

I want to connect up a relay module (wired up to control a normal desk lamp) to an mbed LPC1768 board. I have the circuit connected up successfully using an Arduino via the Arduino's 5V pin. From the ...
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3answers
65 views

Wiring a relay for mains power

I want to make a plug that I can turn on and off with a micro controller like a raspberry pi. I picked up one of these http://www.radioshack.com/radioshack-15a-12vdc-125vac-relay/2750031.html And the ...
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1answer
89 views

High Power LED and relay with the same power supply

I'm rebuilding optical printer (the machine which does Super8 to 16mm film blow-up) and designed new electrical circuit for it so I can control it with Arduino (or maybe later with Raspberry Pi). ...
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1answer
45 views

Is there any wearout mechanism for a relay simply from current flowing?

How will the wear of a relay be affected if the current through the relay is brought to zero before the relay is operated? I'm thinking about having a solid state relay in series with 3 mechanical ...
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1answer
57 views

How to make a latching/unlatching relay circuit with 240V converter

I want to make a circuit that at the touch of a button turns on a 12V circuit controlling LED lights, powered from 240VAC. So I need a latch/unlatched relay circuit after a 12V converter, and I've ...
0
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1answer
57 views

Two flyback diodes in parallel across a relay coil?

I'm using relays that contain a flyback diode internally, so no need to add an external flyback diode. However, I want to provide a place on my PCB to possibly stuff a flyback diode in case I would ...
0
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1answer
40 views

Relay sla-05vdc-sl-c is not working on arduino uno and nano

At first time, trying to check this relay modules (I got 2 the same) they both worked nice - no problem. But now I am going tu build the temperature controller for old fridge (it is working ...
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0answers
43 views

Connecting/disconnecting AC signal via uC

I want to mix up to four AC signals, that may or may not be DC biased, but will always be between -5.6 and +5.6. For that I was going to use a summing amp. (If anyone wants to talk me out of that in ...
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1answer
83 views

Raspberry Pi Intercom, switch using transistor or relay?

I am researching a way of using a Raspberry Pi to act as an Intercom. I already have the intercom system mounted, but it's a very old one and wanna do something to it to be more new technology ...
0
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0answers
42 views

Overriding Mechanical Switch with GPIO

I have a mechanical switch that sends a current (~5Vdc) into one of two wires. simulate this circuit – Schematic created using CircuitLab I would like to add circuitry which can override ...
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0answers
44 views

Can I use a 100-240V AC 5A Time Delay Relay to spread out startup of drives?

My storage enclosure has dual power supplies for failover. Specs for each PSU:100-240VAC 5AMax continuous output power: 250WTotal power on +3.4V & 5.V is 128W mx I need to delay initialization on ...
2
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1answer
41 views

Relay control of AC motors, handling turn-off kickback

I've been researching how to control a smallish AC-motor using a relay, and more specifically, how to turn an AC motor off using a relay. This is a subject that has been up many times at this site, ...
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1answer
66 views

How to wire many bi-color LEDs to a single power supply, and switch them on/off individually

My goal is to have 13 separate stations, each with a bi-color, common cathode LED (Dialight 606). These LEDs do not require external current limiting resistors. Each LED can be 'On Green', 'On Red', ...
0
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1answer
64 views

Relay Solution for Controlling Pumps with Arduino

I'm working on a hydroponics project that requires me to run 10 pumps for 15 seconds every 2 minutes. I was able to set this system up by running a relay board off of an Arduino, but the relays were ...
0
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2answers
28 views

6v switching large load

I'm looking to build a remote firework launcher. I'm using parts from an rc car for the remote, but I need a circuit that can switch a large current (~2-3amps) with 6v. Can I do this with a ...
0
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1answer
50 views

switching power redundancy

I have a load (LEDs) that draws 36V, 5A. The circuit is made in this way: Power Supply (AC-DC) -> LED Drivers (5 in parallel) -> LEDs (5 strips). What component I need to install if I want to add ...
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1answer
40 views

Will a 3-32 VDC input signal relay be damaged (or will work) with a 110 VAC input?

I'm looking at getting a SSR-25DA relay (http://www.amazon.com/gp/product/B0087ZTN08/ref=ox_sc_act_title_1?ie=UTF8&psc=1&smid=A1THAZDOWP300U) and using it with a temperature controller that ...
2
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1answer
82 views

Transformer and a relay in series - but function like in parallel, but not exactly

I've been doing some planning to build a home automation system on top of the existing power infrastructure of my house. The first thing would be making my light switches smart. My original plan is ...
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0answers
28 views

contact resistance

AZ2150 is a power relay that is rated for 40A at 240VAC. It has a contact resistance of <20milliohms initially. After use they say that typically the contact resistance will be between 20-100 ...
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1answer
43 views

Most efficient two-way switch relay and/or schottky (or..)

Scenario: On my old military Land Rover I have a three-way pole switch which turns the pilot and tail lights on (top position), or also turns on the headlights (bottom position). Top: Pilot and rear ...
1
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3answers
98 views

Insufficient current to drive automotive relay?

I'm adding a leisure battery to my van so I can run some stuff with out fear of draining the starter battery. My leisure battery is wired to my starter battery so it can charge from the alternator ...
0
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1answer
33 views

Implementing a safety lockout through ladder logic

The family fireworks show has become my soon-to-be brother in law's and my "thing" over the last couple of years. We have some ideas to make the show better next year, my part is spinning up some ...
3
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1answer
45 views

Can I use the Omron G6RN relay where reinforced insulation is needed beetween coil input and switched circuit?

I want to use a relay to control 230V power to an electric motor. I'm considering using the Omron G6RN relay: http://datasheet.octopart.com/G6RN-1-DC24-Omron-datasheet-10910301.pdf According to the ...
0
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1answer
60 views

16 channels relay control with 3.3v pins

I'm going to buy two 16 channels relay boards from Sainsmart : http://www.sainsmart.com/16-channel-12v-relay-module-for-pic-arm-avr-dsp-arduino-msp430-ttl-logic.html I want to control it with a ...
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1answer
26 views

Autoelectrics: Testing components off 12v battery

I'm quite good with mechanics and am just starting to learn more about electrics specifically applicable to automotive. One thing I am still yet to get the grasp of is the way electricity behaves. It ...