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What is the difference between MOSFET and triac?
1) Mosfets, by themselves, can only switch DC current. Triac can switch DC and AC current. 2) Mosfet is a voltage-driven device and Triac is a current driven device. 3) Triac is self-sustaining and Mosfet is (practically) not self-sustaining.
What is difference between relay and triac?
When to choose a triac over a relay? Triacs are semiconductor devices designed to control the distribution level of AC current because, in a solid-state, its work is silent. Relays work in a simple way – when you energize the coil, the contacts engage. The contacts will open when you de-energize the coil.
What is a triac relay?
TRIACs are a subset of thyristors (analogous to a relay in that a small voltage and current can control a much larger voltage and current) and are related to silicon controlled rectifiers (SCRs). The bidirectionality of TRIACs makes them convenient switches for alternating-current (AC).
Can a TRIAC cut power like a relay?
A triac by itself can’t cut the power like a relay can so you’ll need another pass element that you can turn off and thus turn off the triac. A triac will probably also be destroyed if you take it outside its limits, so there might be some high voltage or current scenario where you can’t find a big enough triac, but can find a relay.
What are the advantages and disadvantages of the TRIAC?
Advantages of the triac. No mechanical wear-out. Easier to switch on zero-crossing. (Can also be done with a relay, but less accurate due to the switch-on delay) Can be used in dangerous environment, particularly in explosive sensitive environments where sparking relay contacts are absolutely out.
How is a TRIAC used in an AC SSR?
A TRIAC is also commonly used in AC SSRs. Below is a typical TRIAC circuit. L1 may not be used. C1 & R6 form a “snubber” and values depend on load characteristics. Solid state relays are opto-coupled back to back SCRs in their simplest form. You can duplicate that yourself, but it gets a bit messy.
Is the control circuit of a TRIAC silent?
Triacs, being solid-state, are mostly silent. Unless you use a pulse transformer or optoisolator, your control circuit will be at the potential of your controlled circuit (generally the Neutral for your 120/220V circuits).