Electrical Engineering Stack Exchange
Electrical Engineering Stack Exchange

Questions tagged [solid-state-relay]

A solid-state relay (SSR) is a switching device that accepts a small control signal to control a larger load current and/or voltage. In many ways they perform the same function as an electromechanical relay, but without any moving parts. They have many advantages, but also some disadvantages compared to a mechanical relay.

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Designing a Santa alarm (honestly)

You read the title and that's what I am trying to do. Synopsis: I have a young son who is determined to catch Santa (to what ends I don't know). He even dreamed up using some kind of pressure plate and connecting it to a light that will turn on when…
Christian Bongiorno
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Equivalent circuit of a solid state relay

I want to switch 50V AC voltage. Maximum drained current will be 5A. Frequency is 50Hz. Switching speed is not important, can be real slow, it is not a problem in my application. I wanted to use solid state relay at first for this purpose. But as…
hkBattousai
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Why do Solid State Relays cost so much?

Solid State Relay (SSR) Crydom CN240A24: Eur 10.72 Same function with basic components Optocoupler MOC3043 (zero-crossing detect, triac out): Eur 0.726 Triac BTA06-600CWRG (snubberless): Eur 1.16 2 resistors: Eur 0.212 Total for…
stevenvh
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Any obvious problems with this DIY home automation?

I'd like to know if anyone can spot any serious electrical issues in what I'm trying to do from an electrical viewpoint. Youtube Demo http://www.youtube.com/watch?v=BmsdXMbd2vo Short version: I have 220V relays in the house, connected to lights…
vlad b.
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How do I read a datasheet for a solid state relay?

I'm looking to use several (12-18) solid state relays to control a set of water valves (24V AC solenoids, 20ma holding current, 40ma inrush current), and I'm having trouble finding suitable parts, probably because I don't understand the datasheets…
Mark
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Controlling High Voltage device with Arduino

I want to control lava lamps using Arduino. I think it shouldn't be hard project, but I have no experience with hardware projects so I'm not sure witch design will feet best for me. I consider using S202T01 Series Solid State Relays (I already have…
Maciek Sawicki
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Difference between optoisolator(optocoupler) and solid state relay?

I have been looking into relays and optoisolators. I am aware that there are different optoisolators, with some having a transistor on the detector side which allows current to flow in one direction whilst there are others with triacs on the…
Jaimin
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How can I stop a solid state relay from latching up?

I'm trying to use a power relay (PR26MF) to turn on and off a device. The device takes a 9v supply and typically draws ~250mA. I'm finding that the relay turns on just fine, but when I try to turn it off, it won't: it remains latched in the on…
Shawn J. Goff
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Do I need a flyback diode?

I have some experience using automotive relays and triggering them using the output from a two-way radio aux pin so I am aware of the need to add a diode in parallel with the coil to protect the radio's internal transitor when it is turned…
Chef Flambe
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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 with inductor type devices?
user10768
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Connect two different sources with two Digital Ouptuts using an Adam 4055

I would like to operate an Adam 4055 module to control two different applications having their own power supply. Adam 4055 is Digital Input/Output control module over RS-485, I use only the DO part here. Reading the doc, Adam 4055 DO are Open…
jlandercy
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What is the difference between a solid state relay and a transistor?

Along with the difference between a solid state relay and a transistor, I'm also interested to know if there are transistors that act a lot like the typical relay modules you can find on ebay (where you only need a 5V signal from the microcontroller…
Jacob Edward
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Why are bulky SCR power controllers used when the same can be achieved with a relay?

This is kinda noob question. I recently got an SCR Power controller (WATLOW DIN-a-mite DB20-24CO-0000 Style B). This is the first time I actually got to test an SCR controller for myself. The input trigger is 4VDC to 32VDC, which I powered with a…
The_Vintage_Collector
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How fast can I cycle an AC SSR?

I have a PID/heater setup I am driving with an arduino. I'm using the Opto 22 MP240D4 solid-state relay to switch about 1A 120V 60 Hz (resistive heater). It's not clear from the product sheet or the datasheet whether it is zero-cross turn-on, or…
DeusXMachina
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Transistors: why are resistors needed?

I have a solid state relay which needs at least 3V to activate, and I need to toggle with a 2.3V output from a microcontroller. I've also got a 6V 1A power supply which I can use to power the relay. I understand I need to use transistors somehow and…
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