All Questions
27
questions
4
votes
1
answer
170
views
What is the purpose of diodes on the gate of a silicon bilateral switch (SBS) TRIAC trigger circuit
Here is a typical TRIAC SBS trigger circuit to control a resistive load. This example is from the BS08A datasheet but there are plenty of others.
What is the purpose of the D1,D2 and R3? It appears to ...
- 143
0
votes
1
answer
147
views
Schematic of a simple zero-crossing triac switch
I have a triac in a 60Hz 120V power line (as is often done for dimming)
and want it to only switch on the power when the AC voltage is low
(widely between -40V and +40V would even be fine).
This is ...
- 544
1
vote
2
answers
960
views
TRIAC dimming using MOC3021 with two or more lights are connected, in off condition lights is some blow
In this dimming circuit I'm using BTA41/BTA16/BTA39 and MOC3021.
There is 1 light is dimming is running smoothly, but when 2 or more light is connected, in off condition lights are blowing dim. Where ...
- 69
1
vote
1
answer
332
views
I don't understand dimming on 3 quadrant TRIACs
Can someone help me understand how dimming works on 3-quadrant triacs? I understand they are great because they have higher reliability and don't need snubbers. What I don't understand is how 0-100% ...
- 115
0
votes
1
answer
187
views
Phase cut dimming driver for panel lights having occasional flick
I am designing a phase-cut dimming driver for Incandescent bulbs as well as LED panel lights with dimmable drivers.
Using a BTA24 Triac and VOT8121AB Optocoupler driven by my MCU.
For zero-cross ...
- 109
1
vote
0
answers
144
views
Uneven Brightness Curve When Using Digital Triac Dimmer on Neon Transformer
I am working on an AC dimmer project using the following circuit:
This circuit functions by detecting zero crossings in the AC power input via the LTV814 optocoupler connected to a pull-up input pin ...
- 495
0
votes
1
answer
499
views
Can a Triac be driven using only positive voltage due to the laws of Q1 and Q4 quadrants?
I have a BTA12-600B Triac and an Arduino.
Is it possible I can trigger both positive and negative amplitudes of an AC cycle by suppling only a positive voltage from the Arduino digital pin to the ...
- 11
4
votes
2
answers
891
views
Getting problem in triac based fan speed control
I'm using this circuit to control the speed of ceiling fan. The fan speed is divided into 8 steps. (0:off & 8:full speed) with 100us gate pulse.
This circuit works with incancescent light bulb ...
- 903
0
votes
2
answers
98
views
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 ...
- 229
0
votes
0
answers
496
views
RFI filter modeling in LTspice w/ triac
I have a few questions about modeling an RFI filter in LTspice with a triac-based dimmer circuit. I'm referencing the circuit described in Figure 11 in Triac Principles and Circuits -- Part 2 (Nuts &...
- 343
2
votes
1
answer
1k
views
Help for voltage is being passed trough load, even triac is OFF condition
We are using below circuit for home automation. We are facing problem when 5v battery is not passing to the circuit,but even 1 volt is being passed trough load, even triac is OFF condition.. Please ...
- 21
0
votes
2
answers
2k
views
RobotDyn dimmer controlled by ESP 07 only results in flickers
I use a dimmer module connected to an ESP07 which has Node MCU firmware.
I'm using the Z-C interrupt to skip sinusoidal pulses, however I only obtain flickering instead of dimming. The light is bulb ...
1
vote
1
answer
496
views
Triac misfires because of noise from inductive loads
The product is a wifi enabled smart switching device. One device has 4 different channel for four different appliances to be connected to the product. Each channel has a pair of optocoupler and triac ...
- 222
2
votes
1
answer
943
views
Arduino To Control Light Intensity
So I want to build a circuit that can control the intensity of a light bulb (powered by 220V AC, 60 Hz) through the output voltage of Arduino.
I know I must use Triac but the question is, is the ...
- 49
0
votes
2
answers
3k
views
Which way I should go, Relay or Triac Switching?
I am developing one consumer product in which I am going to operate Resistive and Inductive loads. In this project there is also a need of dimming of the loads.
I have completed programming part. ...
- 245