Questions tagged [diac]
A DIAC is a diode that conducts only after its breakover voltage has been reached momentarily. (From: Wikipedia)
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Why is this light-dimming configuration flickering? Why is it not stable?
My question is why is this configuration showing an unstable flickering voltage accross the light bulb? Were incorrect capicitance values used?
Observing the oscilloscope, I note that there is some ...
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Why are R1 and C4 connected in parallel to output in the following dimmer circuit?
I'm trying to understand the following dimmer circuit I found from this website: https://electronoobs.com/eng_circuitos_tut80.php:
Why are R1 and C4 connected parallel to the Triac? I have read some ...
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Analog Timing Circuit with DIAC
I am currently trying to come up with an analog timing circuit to use within a solar tracker. I know using a 555 timer would be relatively easy to do here but I wanted to see if I could come up with a ...
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Controlling minimum voltage output with a DIAC/TRIAC dimmer circuit
I purchased a hot plate/magnetic stirrer from Amazon (Model SH-2, a very common cheap device from what I've found) and would like to alter the circuit so that the minimum temperature from it is lower ...
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Can I use a TRIAC as an AC switch and an LDR as a switch controller to turn on and off a LED bulb?
I want to use a TRIAC as a switch for an AC light bulb and turn on the bulb when it gets dark and turn it off when it gets light using an LDR.
I want to fully cut off the bulb below a certain ...
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Help with this 3-phase thyristor triggering board
I need a triggering board which is able to drive thyristors such as (s8006l), and I found this board on Aliexpress which might be the hidden gem I am looking for.
enter link description here
enter ...
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What is the importance of R1 connected in this circuit?
What is the importance of R1 in this circuit? What would happen if I removed R1 and kept VR1?
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Help me to simulate this DIAC-TRIAC circuit
I was given to simulate the circuit in the lab. The picture of the circuit from the manual is given below.
I made the same circuit in LTspice.
The problem is that I do not get the expected output as ...
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DIAC/TRIAC heater control suddenly switches to max power after a short period
I am trying to build a heating mantle and I decided to use a DIAC/TRIAC pair to control the power, like this:
simulate this circuit – Schematic created using CircuitLab
I realize that there are ...
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TRIAC not triggering in 3rd quadrant but works perfectly in 1st
Good day. I am designing a power control circuit for dimming a 100W bulb using BTA16. In the circuit shown below, when I apply power to the circuit I only receive the positive pulse at the output (of ...
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TRIAC BT136 as DIAC BD3 conversion both have MT1 and MT2
A DIAC looks like a diode.
A TRIAC looks like transistor.
I have project that uses a DB3 and a BT136, but the BD3 is not available in the local market.
Can I cut the gate terminal off of a BT136 to ...
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TRIAC Voltage Control
I have the simple Triac voltage control circuit.
The values of resistance and capacitor are 10 kohm and 0.1 uF respectively.
I want to know that the following:
How can we calculate these values of ...
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Light dimmer not working
I made a light dimmer from this circuit below but doesn't seem to work. It seems to work with vloggers online but they are using 220V mains, I'm using 120V. I'm guessing resistors values may be the ...
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DIAC datasheet's circuit is not in series with TRIAC's Gate
Being my first time to use a Triac and a Diac to control an AC signal, I read many questions/answers in this forum related to DIACs controlling TRIACs, all being very helpful.
Now, I see in a MOC302 ...
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How is Gate Trigger Current determined in a "dimming" circuit?
EDIT: DIAC part numnber is DB3TG
I'm trying to understand how a dimming circuit works, specifically TRIAC control. The TRIAC (D1) in this circuit is a BT136S-6. Where does the Gate Trigger Current ...
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A question on thyristors and phase control
High schooler here reading on thyristors.
Videos online and books say they can be used as light dimmers. I assume that's because we can control the amount of current that can enter a load. But what ...
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DIAC in series combination?
I wanted to make a cheap and simple high voltage protection circuit which can turn off my appliance for 10 sec when high voltage hits. Generally DIAC works on 30volts. I have dozens of these DIAC I ...
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How to explain how the DIAC and TRIAC works in a digitally controlled fan regulator circuit?
There are two version of the circuit that do the same thing. One with capacitor, and, one without.
The schematics below depict the circuit needed for diac/triac activation properly. (I have missed out ...
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Designing a triac based regulatable DC supply
I need about (30V-160V)32A DC for my project. I am trying to build an electronic circuit to regulate AC mains (220V, 50Hz) to produce voltage from 30V to 160V and rectify it to produce DC voltage. ...
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Simple DIAC circuit which I do not understand - LTspice
Here is the circuit :
Here is the model and the parameters of the DIAC :
...
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This Potentiometer Keeps Catching Fire And I Can't Locate The Short
Device: KADA 852 Hotair rework station (not 852D)
VR9 keeps catching on fire and R42 is half toasted but still keeping its resistance, I removed and checked CA12 and CA13 and they are not shorted. ...
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How do DIACs work?
I edited my whole post for more refreshed information I learned about DIACs.
Let's consider the following circuit and how it works:
First of all the Vs must be higher than break voltage of DIAC so ...
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Capacitor in parallel with relay coil backfires on contacts
I've got a smoothing capacitor(2,2uF) C1 in parallel with relay coils inside a fullwave diode bridge.
When the circuit is closed through contacts in pre-relay RLY1 it first gives me, almost everytime ...
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Triac control circuit through load
Why is it that in every triac analog dimming circuit I find that the triac triggering circuit is fed through the load and not straight from the mains??
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Questions regarding eliminating hysteresis in ac dimmer
In the following circuit it says:
“This hysteresis effect can be eliminated however, using the circuit from a detailed application note from Littelfuse shown in Fig. 6.4.4. Here the capacitor C1 is ...
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High(er) current AC flasher circuit
I'm trying to develop a flasher circuit for an aircraft warning light like the one shown here. The light will be powered with 120 VAC providing 15 A.
I'd like to use transistors (BJTs, MOSFETs, ...
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110V sewing machine plugged into 220V - DIAC blew?
Our 110V Brother sewing machine got plugged into the 220V side of our step down transformer. After a short pop, it does not turn on. I pulled the power supply board out and it seems like just an input ...
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one-way AC power
Is there a device to only allow AC power to "flow" one-way?
Scenario:
I have a circuit in which I would like to draw AC power from two sources: One source is good ole wall (grid) power and the other ...
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SCR triggering using DIAC
I've found this method of triggering of the SCR through DIAC and I'm trying to understand it. I was able to figure out the whole trigger circuit and how to compute the values of RC in order to have ...
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Two or more Diac Triac dimmers in parallel
I wanted to know whether connecting two or more simple diac-triac ac lamp dimmers in parallel with the same load cause any problems?
I do not want to connect them in series, just parallel will be ...
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Zero crossing detection and Light dimmer
I am confused by zero crossing detection of opto-triac. I know what is the zero crossing detection or switch. (ZCS)
Zero crossing detects what is the point that wave is going to positive to negative ...
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What is the correct method for Triac supply?
I need to know what is the correct power supply for fallowing light dimmer circuit that operate by 230V/50Hz AC supply.
It should be neutral(N) to MT1 or live(L) to MT1?
If can use both, what is the ...
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Can someone help me understand DIACs and TRIACs
These are something that has confused me for quite some time. Just like a lot of you, I'm sure, I'm a tinkerer. I like to take things apart, salvage parts, etc. A lot of stuff I take apart have a ...
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Is it possible to replace a DIAC circuit with an SCR circuit to drive a TRIAC
I have a triac DIAC cirtcuit. I don't have any DIACs on hand, but I do have plenty of TN1215s. Is it possible to generate the required pulses using an SCR to drive the TRIAC's gate?
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Phase control up to 40A with TRIAC and DIAC (Optocoupler)
I'm projecting a phase control to control the power given to a resistive load of 6 Ohms using a PLC, TRIAC (BTA40-400), DIAC (Optocoupler MOC3023) and a zero crossing detector (4N25).
I've simulated ...
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Why isn't the switches being bypassed in this triac/diac circuit?
Just when you think you understand circuits, there's always a curve ball to derail you and leave you scratching your head.
The diagram below is a Triac/Diac speed controller for a reciprocating saw. ...
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Light dimming regulator circuit
Here in this circuit,
We have the load connected to a diac and triac circuit along with a variable resistance and a capacitor.
When the circuit operation begins initially, the energy is stored in ...
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A question about very simple light Dimmer circuit?
I've learned that a Triac works as a switch for controlling AC current. Why not connecting the load (L1) and Triac in series? at the position of red arrow? My reason is that a small amount of current ...
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