This universal triac controller circuit with optocoupler solves the problem that triacs have when functioning at low temperatures (triac needs higher gate current) by adding a transistor at the output of the optocoupler circuit.
The transistor amplifiers the trigger pulse coming from the optocoupler and the gate current is high enough to trigger the triac in all temperature cases.
How does the circuits works?
The base of the transistor is driven by the OC. C2 works as capacitive bias resistance to avoid power losses and it also helps avoid DC loading of the supply line. The switch current is limited by R3. D1 works as one-way rectifier while C1 works as ripple filter.
D2 stabilize the rectified voltage to 15 V.
T1 conducts when the OC sends a pulse to its base. C discharges through the collector-emitter line. The trigger current is limited by R2 to around 40 mA.
The discharge current time of C1 is less than 1 ms.
The RC circuit R4 and C3 protects the triac from voltage spikes.
This is very important in all inductive loads.
The transistor amplifiers the trigger pulse coming from the optocoupler and the gate current is high enough to trigger the triac in all temperature cases.
How does the circuits works?
The base of the transistor is driven by the OC. C2 works as capacitive bias resistance to avoid power losses and it also helps avoid DC loading of the supply line. The switch current is limited by R3. D1 works as one-way rectifier while C1 works as ripple filter.
D2 stabilize the rectified voltage to 15 V.
T1 conducts when the OC sends a pulse to its base. C discharges through the collector-emitter line. The trigger current is limited by R2 to around 40 mA.
The discharge current time of C1 is less than 1 ms.
The RC circuit R4 and C3 protects the triac from voltage spikes.
This is very important in all inductive loads.
Heya¡my very first comment on your site. ,I have been reading your blog for a while and thought I would completely pop in
ReplyDeleteand drop a friendly note. . It is great stuff indeed. I also wanted to ask..is there a way to subscribe to your site via
email?
Electrical Project
yes! i am working on it . I will surely give you a way to subscribe in some time. please wait. thanx for your comment.
ReplyDeleteespecially for beginners or amateurs, i saw you useful. Thanks for your wide explanations although it's simple to someones.
ReplyDeleteThis website and I conceive this internet site is really informative ! Keep on putting up! Magnesite flooring
ReplyDelete