Tagged Questions

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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1answer
33 views

Will a tvs diode help my relay with inductive loads?

I am not an EE, so please be gentle! I will obviously get a certified EE to review my design before anyone else touches this so please assume that I know enough to at least be safe with 120VAC and am ...
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2answers
25 views

Building circuit for n-relays using flip flops, is this the best solution?

I'm trying to build a circuit for n relays, each relay should hold it's state (ie latched). My first Idea was to use decoders, but clearly this was a bad option, since the state of the relays won't ...
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2answers
79 views

Activate a buzzer when power goes off

I am totally new to electronics so I would like to have your help. The project I would like to build is very simple but yet I don't know the name of the parts that I have to use. So, I would like to ...
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2answers
19 views

Wiring CanaKit Relay and Southco EM-05 Electronic Lock

I am attempting to wire this relay http://www.canakit.com/4-port-usb-relay-controller.html to this lock http://www.southco.com/en-us/em-05. I have done some work with Arduinos before, but I am not an ...
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1answer
42 views

Explain operation of solid-state relay

Link for Datasheet: http://www.ixysic.com/home/pdfs.nsf/www/CPC1230N.pdf/$file/CPC1230N.pdf This is the relay I am using in my circuit, but I am not getting how it connects/disconnects and flow of ...
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2answers
54 views

What is the purpose of using only the coil of a relay?

In these two examples: http://www.electronicecircuits.com/electronic-circuits/cd4060-timer-circuit-1-minute-to-2-hours/comment-page-4#comment-48679 http://www.zen22142.zen.co.uk/ronj/24hs.html A relay ...
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4answers
125 views

Relay alternatives that are silent and support 500mA+

What can I use as a silent "general-purpose" relay alternative? There are various scenarios where I will need a relay-like device that allows me to control one circuit with a separate isolated ...
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3answers
82 views

Audio Signal Switching - “DPDT switch vs. 4066”

I've got a signal coming from an electric guitar and I need to switch it. Basically it's a distortion circuit. I need to switch between the distortion and clean (directly connected to the output) My ...
0
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1answer
86 views

Controlling multiple relays with Arduino

I've tested controlling single 24VDC relay with Arduino by using external power source to power the relay. Now I've set up a board to control several of these relays, but noticed that the Arduino ...
0
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1answer
25 views

What things to think about when selecting a relay for controlling small valves?

We are creating a novelty drink dispenser that controls a set of 8 pumps with a Siemens Simatic Step7 1200 PLC. The decision to use this PLC was based on our need to have a very stable prototype. Now ...
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1answer
37 views

What kind of time delay switch to choose to reverse motor for just a couple of seconds

I would like to know the following: I have a motor driving a lead screw which transports a part either up or down. When going down and something comes in the way a switch gets triggered by the ...
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0answers
51 views

Audio via transistors

Is it possible to push an audio stream through transistors or a DPST relay? I'm using Arduino to do selection between two audio sources and two destinations, and I've completed the first part which ...
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2answers
70 views

Troubleshooting circuit in make Electronics Book (Experiment 8) [closed]

I created the same circuit as in Experiment 8 of make Electronics book but cannot get it to work in the same way as described in the experiment. When I connect the circuit to the power source and ...
0
votes
1answer
32 views

Relay circuit for circulator pump and actuators

I need help designing/wiring a circuit for thermostatic relays, which control electrothermic actuators. Basically I have 4 actuators and thermostatic relays, which pretty much is just a 12vDC ...
0
votes
1answer
97 views

Normally closed SSR won't work with grounding out a magneto's primary to ground

I've been trying to find a device that will ground out a magneto's coil (primary kill wire) in a normally closed state without using a mechanical relay because I want my circuit to be all solid state. ...
0
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1answer
56 views

Use Arduino for switch a 12v powered remote control

I've a remote control powered by a 12v battery. I need to switch a button using arduino, can I use directly the digital pin without any relay or transistor? Thanks in advance
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2answers
93 views

Circuit seems to lack something

http://www.electronicecircuits.com/electronic-circuits/cd4060-timer-circuit-1-minute-to-2-hours I've replicated the circuit in the given link but \$D_2\$ in my circuit doesn't work at all. Also, the ...
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2answers
52 views

Using DPST Relay to control AC Load

Below is the functional schematic that I am planning to use to control an AC load (air conditioner in this example with max current draw of 32A). Since I am still relatively new to mains power and ...
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1answer
45 views

Mains into a relay?

Will hot/live go into NO and neutral into COM, to switch over 200v? Can someone explain please. I saw in some places it says natural into NO but what into com?
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0answers
67 views

Relay voltage drop, a solution?

I simulated an H bridge with 2 relays and one motor in PROTEUS. Everything is 12 V and DC, I set relay coil resistance at 80 ohm ( I am replicating this : ...
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0answers
34 views

Mounting SSR + HEATSINK

I have made a AVR based Bluetooth mains controller. The idea is to be able to control my AC using my phone. Since I would be controlling an AC, I figured I would be needing a solid state relay with ...
2
votes
1answer
56 views

Using a MOSFET or BJT instead of solenoid

I'm trying to convert all relays and solenoids to transistors in a circuit to make it solid state. I have a small (150cc) 12V DC starter motor that is currently turned on by a small transistor turning ...
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1answer
55 views

I need 2 vcc pins on the arduino?

I need to connect the vcc pin to a bluetooth module but then I need to sue it again for a relay module what do I do?
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0answers
19 views

How can I control an IR204E in a PK543A to remotely operate this apartment door buzzer? (What relay do I need?)

My apartment door 'suite station' (buzzer) is a TekTone IR204E (pdf). It has an option for talk, listen, and open door. It contains four wires labeled 1, 2, 3, and X. My research leads me to believe ...
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0answers
55 views

How to control a bulb operating on 230v using a switch operated at 5v

Hello Electrical engineering community, Maybe this is an easy question to answer but I am new to this so definitely need assistance. I want to control a bulb which is driven via 230v AC mains using ...
0
votes
1answer
48 views

Running a load off a solar panel connected to 2x 12V batteries.

I am having trouble figuring out what relay I should be using for my solar panel set up. I have a solar panel running to a solar charge controller. I then have the controller running into a relay. ...
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2answers
214 views

Circuit Protection re: Relay Coil

Is the flyback diode adequate protection in for the microcontroller in the following circuit? simulate this circuit – Schematic created using CircuitLab Will my circuit experience over ...
0
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1answer
91 views

Chattering relay on microcontroller power supply

I am working with a device that has a relay on the 12v power supply to the micro controller that runs the device. Under certain unplanned circumstances this relay can chatter. What is the potential ...
0
votes
1answer
36 views

I am looking to isolate an inverter when power from a generator is applied- debounce relay?

I have tried to find specific info on this scenario with no luck The situation is this; Off grid power system 12v battery store runs 12v lights etc. and an inverter for things difficult to run or ...
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0answers
46 views

Relay is not isolating properly its sorrounding circuit blocks

It turns out I've been building up an elevator for a project (at College). In general terms, everything appeared to be correct, regardless that I hadn't simulated each part. I decided to begin with ...
0
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2answers
39 views

Relay circuit for AC application

I am using relay circuit for inverter application. It's 12V relay having coil and two contacts for connecting line and neutral respectively. But, I am not getting closed connection when I am giving ...
0
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2answers
53 views

Smartphone headset jack to relay [closed]

Looking to see if anyone has seen a relay triggered by a sound file played thru the phones headset. My idea is to connect an old smartphone to my home's WiFi and then connect it to my garage door ...
0
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2answers
91 views

How do I read this relay pinout/schematic?

I'm trying to understand the way this relay works. To me it looks like this KUHP-11DT1-12 is a DPDT relay. Pin 7 is connected to 1 or 4 and pin 9 is connected to 3 or 6 depending on whether the coil ...
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0answers
62 views

How do I protect digital design from EMI?

I have built a system that controls a 3 phase induction motor. Unfortunately I don't have schematics, but the system is simple: A 24V DC contactor switches AC to the motor. 24V is fed by a separate ...
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2answers
101 views

I want to operate a DC 9v relay with a small power

Can a lightbulb be switched on using two mobile phones? (Make a call and the bulb switches on) I need this for a kid's school project so the questions like should the bulb keep glowing after the ...
0
votes
1answer
90 views

Relay that detects 240VAC and switches 12V DC

I'm wishing to detect the loss of AC power (in this case 240V) and when this event occurs have a 12V DC circuit go to earth. This will trigger an alarm for users to react to situation. Can anyone ...
0
votes
1answer
61 views

Why solenoid valve when a liquid pump can be electronically controlled?

In some quick research online, I'm often seeing configurations where a liquid pump is used in tandem with a solenoid valve on the same liquid path. So, let's say I have a very simple scenario: a ...
0
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0answers
31 views

How does the impedance of the source effect the positive sequence impedance measurements of distance relays?

How does the impedance of the source effect the positive sequence measurements of distance relays in relation to power system protection? I wrote that increasing the source impedance decreases the ...
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2answers
117 views

Replace mechanical switch with transistor? MOSFET? Relay?

If I have a switch in some consumer electronics that I take apart, and want to replace a mechanical switch with a digitally controlled one, which component should I use? The only problem I see with ...
2
votes
2answers
158 views

Relay “sticking”

We are experiencing a problem where the mechanical switch of a SPST NO relay (COTO 9007-05-01) is not opening back up when the coil is de-energized. Current keeps flowing through the switch until we ...
2
votes
1answer
52 views

Issue getting relay to trigger, coil voltage might be insufficient

I have a simplisafe home alarm system. All components of the alarm(keypad, base station, sensors, alarm) are wireless, so there are no wires running to any sensors. I wanted to add an additional siren ...
1
vote
2answers
73 views

Problem with a relay

I'm quite new to the electronics, and I'm currently reading a book to learn it. In the chapter I'm in, the author is talking about relays, so I tried to make a simple circuit using a relay IM46. Here ...
0
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2answers
74 views

WiFi relay to DC motor

I'm trying to use a 12 volt WiFi relay setup to control a 12 volt DC motor. The WiFi relay has eight 10 A SPDT relays in it and the motor is 15 A. I understand how to wire it directly to the two ...
0
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0answers
66 views

High voltage low voltage switching circuit

I am working on a project which involves switching of a point from AC mains to low voltage ground when I start my low voltage circuit. Till now have come up with following circui. 1) Point A in the ...
1
vote
2answers
77 views

AVR main loop interference with relay

I'm working on a test program on an ATmega164A that toggles a 12V relay on and off (with no load) through a ULN2003A. For my test program, I'm toggling the relay at 100ms. I've got an IN4001 diode ...
2
votes
1answer
75 views

Contactor control circuit

I am trying to understand a contactor control circuit that I took apart from a broken GIGAVAC GX14BAB. Here is a list of parts that I think are the closest representation of what is on the PCB: ...
0
votes
1answer
85 views

Determining Voltage and DC/AC from Wiring Diagram for Spark Door Buzzer

I'm looking to use my Spark Core to control my door buzzer in my apartment. I'd like to identify the correct parts I need to build the required circuit, but this seems to be dependent on the voltage ...
2
votes
1answer
120 views

General wiring questions: high power LEDs, relay and microcontroller

I think I understand the Raspbery Pi GPIO pins and most of how this diagram below works, at a high level at least. First question, it's not clear to me exactly how the middle part with the ...
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0answers
43 views

Remotely Toggle Relay

A while back I decided I wanted to get into electronics, after which I bought a number of components to get me started, along with the Raspberry Pi and breadboard I already had. I am now wanting to do ...
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2answers
305 views

Why would I need a relay between a DC motor and my Arduino?

I was told that I should put a relay between my 5V motor and my Arduino. I asked why, but they didn’t know. Why do I need to separate them with a relay? The motor requires 5V and the Arduino provides ...