Why is Diode used in PLC circiuts?

yes, diode can be used as rectifier diode to convert ac to dc

A PLC is programmable logic controller (PLC) or programmable controller is a digital computer used for automation of electromechanical processes.

zener diode is a revers bias diode which used for voltage regulation.

yes ofcourse diode can be used as rectifier but it's an uncontrolled rectification.

An ideal diode is a simplified model of a diode that does not exist but is used for simple circuit analysis. A practical diode is the real thing. A model of a practical diode used for circuit analysis purposes includes many parasitic components in addition to the diode.

A diode is used primarily as a Rectifier

varactor diode is a correct answer

The zener diode is used for rectification and stabilisation.

flyback diode is used across Inductive load basically sometimes called a snubber diode, freewheeling diode, suppressor diode, or catch diode is a diode used to eliminate flyback, the sudden voltage spike seen across an inductive load when its supply voltage is suddenly reduced or removed.

The difference between the pn-junction diode and the zener diode is that the pn-junction diode is used for rectification while the zener diode is used for rectification and stabilization. Also, the zener diode can function in the breakdown region while the pn-juntion diode can not function in that regime.

The type of diode used to convert alternating current in to direct current is the power diode.

It's a high voltage diode, typically used in microwave ovens.

A zener diode cannot be used as switch.

diode is a semiconductor which used to flow the current in one direction like pipe

A diode is used to stop the negative voltage swing in an AC signal, so you only get the positive portions. http://www.answers.com/topic/diode-rectifier

legal an specfic zener diode.

The use of the pn diode is for rectification. It can also be used as a switch.

A diode is used as a rectifier, clipper and to get square wave form. The combination of diode (bridge) is used for full wave rectification. It also used as a voltage controlar. Different types of diodes have different uses in different appliences.

A Photo-diode is used to receive light. whereas the L.E.D. is a Light Emitting Diode.

Silicon diode can bear more temperature than germenium Easily available

No. An ordinary diode, be it silicon or germanium, conducts in one direction only, whereas a zener diode conducts in both directions, but at different voltages. An ordinary diode is used to rectify, using its forward bias characteristics, while a zener diode is used to regulate, using its reverse bias characteristics.

A diode is a one-way gate for electrical current to flow through. You must have the right size diode for the amount of current that will be used in your circuit. The stripe on the diode is your output end. That is, the current must enter your diode at the non-stripe end and leave at the end with the stripe. This coincides with the diode symbol used on your schematic. If your diode is in backwards, the circuit will not work as the gate in the diode will block the current just the way it should.

A Soft-Logic-Controller is a PC being used as a Programmable Logic Controller, or PLC.

Not sure of your context. A diode is a diode. One artificial distinction might be that an electric diode refers to a diode used in a higher power application with more current where an electronic diode might be found on a circuit board as part of an electronic lower power application.

1.0A RECTIFIER diode used to convert ac power to dc power