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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42 views

Remote controlled socket issue relay [on hold]

I have bought a remote controlled socket (ebay url given below). I connected it to an extension box (LED TV, Settop box and a small amp, totaling roughly about 250 watts) and I am in India(220V AC, ...
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1answer
20 views

Raspberry Pi High Voltage Supply Soft Off Circuit

After looking at various designs for a "software" controllable power off circuit for a raspberry Pi computer I decided none of them fit my need so I designed my own. Before I commit it to a PCB for ...
0
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3answers
156 views

How do I get a digital signal from a switch?

I want to essentially drive a relay using a switch. For eg: If the switch (AC Voltage : 220v, 50Hz) is switched on, it sends a digital signal to the relay to switch off.
0
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2answers
96 views

limit switches to control motor direction

I am trying to use two limit switches and two DPDT relays to control the direction of the motor. When the power is applied the motor should rotate one direction (direction for this question isn't ...
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2answers
96 views

Two relays for DRL on a car

I am trying to make a circuit for my newly installed DRL (Day running lights), what I am trying to do is have the DRL run all the time, turn off when using high beam, dimmed when headlights are on. I ...
1
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0answers
74 views

Insufficient Power when using one power source vs two [duplicate]

So I've been working on a wireless remote relay switch using several components and have struck a break wall. The issue I'm having is that the D0 siginal output triggers the relay but only at short ...
0
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1answer
46 views

Control relay from Bluetooth on ATtiny85

I know someone else has made a Bluetooth transmitter to a relay so i wanted to ask a few questions about it being possible? I am an almost newbie at electronics but i do know a few things, so first of ...
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1answer
44 views

How to increase current output of a multiplexer for activating a relay

I want to make a multiplexer for my project which needs 24v dc to operate. I am using an OR Gate IC for generating an output. My 4 gate inputs are connected to 6V battery power and I am getting a 6V ...
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1answer
65 views

How can I amplify cellphone's vibrator signal to switch my home electricity on or off?

I need to connect my Samsung s1 cellphone to my home's lights when I am away. I realised that I can use my cellphones' vibrator signal when I call my "Home" cellphone number. I know that the mentioned ...
2
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1answer
61 views

voltage regulators destroyed — protection diode needed?

I have the following basic circuit: As I was flipping the button to turn the relay on and off, I noticed sparking from the voltage meter, and it eventually caught fire, releasing the magic smoke ...
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2answers
71 views

How do I active the relays on this relay bank?

I purchased 2 "Mechanical Relay Board, 8 gang, 10A 220VAC, 24VAC 30ma coil" relay banks that I am trying to control from a raspberry Pi. To do this I've built out 2 595 shift registers and I'm using ...
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1answer
99 views

Minimum permissable load for a relay

I understand the purpose of the minimum permissible load (for contact wetting) but I want to know the relationship between the voltage and the current. For instance, the above table states that the ...
2
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3answers
88 views

What are UL Contact Ratings in a Relay Datasheet?

These UL contact ratings are listed in the datasheet for a Tyco relay: T90 Series, 30A PCB Relay. (Note: the link will ask you to download the PDF, as do most Tyco PDF links) The contact life is ...
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3answers
53 views

Standard Relay vs SSR vs TRIAC for Switching CFLs

I'm confused weather I should go for a standard electromechanical relay (EMR) or a sold state relay (SSR) to switch CFLs @ 220V with 100W max load. This is for a commercial product with the following ...
1
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2answers
64 views

Actuating a relay (either 5V or 12V) with 3V

I am trying to figure out how I can actuate a high amperage 12V relay with only the batteries I have on board. Basically the idea is here to have a 3.7V lithium cell, a momentary switch to actuate ...
0
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1answer
113 views

SC2272-M4 Behaviour when using relay SRD-05VDC-SL-C 5V DC

I'm currently encountering a problem when using a relay switch with a 5v receiver. When using the same receiver with a row of LEDS it works flawlessly. I've noticed that the relay keeps making the ...
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1answer
53 views

Connecting common of relay with main cable of 240VAC

I trying to control my turntable switch with Arduino. This is a toggle switch with 3 wires one wire is for CW rotation the other one is for CCW and the other cable is main with 240VAC. I am using this ...
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1answer
98 views

SRD-05VDC-SL-C 5V DC relay not working with XY-DJM-5V

I'm just a beginner and need some assistance. below is a diagram of a 4CH reciever which works fine with some leds and it reports 5V positive on Data0 when holding channel 0 on the transmitter. What's ...
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1answer
47 views

PSC motor driver circut using relay

I am working on a project in which i need to connect Permanent Split Capacitor(PSC) AC motor using relays as shown in the below block diag fig 1. I want to rotate it in both CW and CCW direction. It ...
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1answer
37 views

How to use LM56 to switch on/off a 2kW heater

I have an oil heater at 220V/2000W so lets say 10A. I was thinking of creating a circuit to switch the oil heater on/off with a LM56 (http://www.ti.com/product/lm56). Is it possible using a relay or ...
0
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1answer
36 views

Remote Wireless 4CH Switch On/Off - Data PIN Network Cable

Planning Stage I'm in the planning stages of making a wireless on/off switch that will basically cut off pin 6 on a network cable. I know little about electronics and I've attempted to learn as much ...
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2answers
118 views

Timed LED circuit with ATX PSU, help

I want to make a circuit that turns on and off the light (LED) of a given time (eg. on 9 pm and off 6 am). I also want it to be adjustable. My idea about the design: I will be using an ATX computer ...
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1answer
71 views

Switching a relay through a wireless connection

I want to create a circuit which will wirelessly drive a relay. I only have a little experience with Arduino. I know what peripherals I need, but I don't know what micro-controller to use. I made a ...
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2answers
176 views

Power switch with slow control signal

I am trying to switch on and off a circuit that draws about 0.8 amp at 12 V. The obvious choice is to set a MOSFET. The problem is that the control signal (the one that goes on the gate of the MOSFET) ...
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3answers
71 views

SPDT Relay with 8Pin

I needed a SPDT relay with 240Vac so I bought this relay from Maplin http://www.maplin.co.uk/p/15a240vac-spdt-miniature-relay-n07aw But I am heaving problem to wire this relay because it has 8 pins ...
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2answers
61 views

Control automotive AC switch via TPS voltage

The A/C compressor is engaged via a single wire that comes from the 'A/C' button on the dash board. I want the A/C button to disengage when the throttle is at 50%. The throttle position sensor (TPS) ...
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1answer
69 views

Controlling a bank of relays

I have a project that requires me to control a set of relays (up-to 24 of them). The current setup is using Wago Speedway 767 field-bus modules. I'm just ramping up so I have to either figure out how ...
2
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1answer
69 views

Contact arcing, how to avoid?

Recently my water heater's thermostat failed. It's just a simple mechanical one, with a piece of metal that "pops" and connects or disconnects the heating element. I would guess that what made it ...
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4answers
101 views

Triple pole triple throw relay

I have a turntable which rotates cw and ccw. This turntable is rotated by AC synchronous motor of 230V. I want to be able to rotate the turntable with Arduino. For this reason I need to control the ...
4
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3answers
370 views

Thermistor control of peltier voltage with Arduino (for DSLR chill box project)

I am mildly familiar with electronics, mostly from playing around with electronics kits as a kid. That was a long time ago, though, maybe as much as 20 years ago. I am currently working on a cold or ...
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2answers
104 views

Relay specs Question

Can anyone explain to me why there are 2 maximum voltages/amperage for both AC and DC like below ? 10A 250VAC 10A 125VAC 10A 30VDC 10A 28VDC I was thinking that the one on the left is for ...
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1answer
43 views

Can a 2W supply power the Relays

I'm designing my first circuit with 2 relays JQX-15F / 005-1Z1 NO20A/NC10A 240VAC(datasheet, probably the SPDT variant) and a 2W ...
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1answer
42 views

Can TPS3700 undervoltage overvoltage monitoring IC drive relay directly?

I am new to electronic circuit design. My current project is to monitor biasing voltage for under/ over voltage using IC from TI: TPS3700. If any of the under/over voltage occurs I will need it to ...
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3answers
112 views

How can I add a power-off delay to this circuit

This may seem simple but I am trying to learn EE. In the below circuit, how can I add a delay when the button is released the relay will stay energized for approx. 5 seconds. My Circuit: ...
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1answer
53 views

Timed Relay Circuit Wiring and Calculating

I am trying to learn electronics and I have a simple circuit in which a button is pressed, a capacitor is charged, then triggers a relay. (With my limited knowledge) I am using a 4.7μf cap and a 470K ...
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2answers
68 views

Latching Relay Driving Idea

I need to drive a 9V latching relay with single cell lipo 3.7V battery. So I designed a boost convertor. It brings 3.7V to 9V and than drive the latching relay with H-Bridge. But with this design so ...
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1answer
68 views

Help using less pins controlling 8ch relay

I know this has been answered somewhere but can't find the solution online. I have an 8ch 5v->120VAC relay controlled by arduino and need help using less digital pins. All channels need to be ...
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2answers
137 views

Power transistor or relay?

I'm going to use a microcontroller to switch a vehicle horn on and off intermittently for maybe one second on and one off for a period of 15 seconds; the horn will pull an estimated 3 Amps. I know I ...
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2answers
94 views

Circuit to switch off circuit “B” for 2-3 seconds when circuit “A” is switched off

Am really a noob in this regards, therefore, need help to build an easy 12V circuit which when circuit "A" is powered off enables "B" circuit to switch off for 2-3 seconds and then turns on. Hopw I ...
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1answer
78 views

How to make a simple Video Switch?

I thought making this would be simple, but I've found it a lot harder than I anticipated! What I mean is that I have one screen/monitor, and two video players (all video is through RGB component, RCA ...
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2answers
67 views

Switching a SPI chip between two devices?

I'm working on a project where it would be very handy to be able to automatically switch a SPI flash chip between two different devices (a programmer, and the system that's actually using it). ...
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2answers
156 views

Transistor as switch between similar voltages

I want to use an XBee to relay data coming from a serial device. The XBee will be sleeping most of the time; waking at regular intervals, powering on the serial device, relaying the serial signals, ...
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2answers
136 views

Flyback Diodes and Relays

I'm wanting to use a relay as a SPST switch, and I've noticed many designs incorporate a flyback diode. What instances are these needed and what are potential drawbacks, if any?
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2answers
80 views

How to protect bistable latching 2 coil relay with diodes?

I know that a revers diode is required to protect a DC coil relay. But to protect this relay RT314F05? It has 2 coils, are 2 diodes enough?
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2answers
101 views

raspberry pi relay

I'm trying to make the Raspberry Pi controlled relay. Searching the internet the whole day, I still cannot get it to work. ( I did not even connect it to the GPIO yet, just using the 3.3v rail). ...
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0answers
36 views

UPS relay circuit

I have acquired about 500amp hours worth of UPS type deep cycle batteries. I am looking to build my own UPS/Charge circuits. (I hope) To charge: I plan on using a standard 110V mains powered battery ...
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5answers
125 views

H-Bridge out of 2 (1 PNP, 1 NPN) Darlington Arrays

I need to control, with a µC, 4 single-coil latching relays and I am exploring various options. My first bet would be a H-Bridge. Since H-bridge ICs are quite expensive and are mostly designed to ...
0
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2answers
72 views

Alternatives to relay/contactors in DC circuits

I wanted to switch a 60Vdc line to ON/OFF using a 60Vdc controlling signal for some kind of a feedback system (yes both are 60Vdc). Presently I have two options visible: Solid State 60Vdc input ...
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0answers
102 views

DC Voltage of a 12V AC transformer after rectification

I want to drive relays using Method 2 of the following question: What is the most economical way to drive an array of single coil latching relays? This basically means that any time the relay is ...
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1answer
84 views

Use a relay as a resettable fuse?

I was thinking; If a relay is used to power a circuit AND itself, if the circuit is shorted - the relay should lose its own power and turn off - almost like a resettable fuse. To power it up, I would ...