Programmable Logic Relays

What is a logic relay?

A logic relay is a programmable relay with a number of inputs (typically 8) and a number of contact outputs (typically 4).
The logic relay includes a number of timer modules (typically 16), counter modules (typically 16), Time Clocks (Typically 16), internal relays (typically 32) analog and digital comparators and sometimes a digital display that can show messages.
It is common that the program and parameters can be altered from the front panel.
In essence, the logic relay is essentially a minimalist PLC (Programmable Logic Controller)

What do programmable relays do?

The internal components of a programmable relay can be linked together using software, to make an operational circuit to achieve the functionality that would normally be achieved by using a number of discrete components such as counters, timers and relays.
The relays are usually programmed in Ladder Logic ensuring that programming does not need a high level of skill and training. Some logic relays, such as the larger Zelio, are programmed in function block programing and this is more flexible but more skilled and less intuitive.

Why Use a Logic Relay?

The advantages of a programmable relay over discrete relay logic are:

• Phyiscal Size
• Cost
• Reduced Wiring
• Flexibility
• Repeatablilty

Where can you use Logic Relays?

Logic relays can and are used in many different applications in the industrial sector where the logic complexity is to small for a larger PLC, in commercial applications for simple levels of control, in agricultural applications for irrigation control and even in domestic applications for heating control, garage door control, gate control and home automation.

Programming Logic Relays

Programming is easily achieved using the G-soft NX software which uses a graphical interface to enable ladder logic programming.
Want help in learning to program, see the programming 101 training videos and ask questions on the forum.