What is PLC
A Programmable Logic
Controller, or PLC, is a Micro controller Based Device used for industrial automation. These
controllers can make automatic for a specific process, machinery, Home
Automation or even an entire production
line. Latching is used in plc as well as hardware circuit to make the circuit in continuously on condition.
Generally Latching is a circuit used to keep the output continuously in
on Condition. Latching is only applicable for the push button or switches which
has spring act.
When you are using hardware circuit you can use relay or contactors, these
two components is used to make load in on condition. In Below concepts we can
understand the concepts of latching and unlatching circuit by using switches
Case1: When you are using
Toggle switch, latching is not required. Check in below circuit.
In this case toggle switch is used to on the motor, when switch is on
motor gets on, toggle switch doesn’t have any spring action so when you activate the switch motor or load gets activated.
Case2: When we use push button it has
spring action. It will on when you press the switch and it will off when u release
the push button. It will not on continuously.
When
we are using push button to on or off the heavy loads we need to use latching.
Latching can be made by using Electromagnetic relay or contactors.
Here we taken two Changeover Relay to make the circuit on continuously
The above circuit showing that
relay is acting as latching(Holding Circuit). When p.b is activated relay get activated
and motor gets activated continuously. In this case motor will not off.
Latching
and Unlatching Circuit.
Latching is nothing but load is in activated condition, Unlatching defines deactivation. In this circuit we taken two push button.
i.e start and stop, Electromagnetic Relay is used for latching.
When switch is pressed
motor gets activated immediately and when stop p.b is on load will get deactivate.
Comments
Post a Comment
If you have any Doubts plz let me know