Relay#

The Relay block is a model of a simple classic relay with two stable states. The model operates according to the following algorithm:

if the input signal is greater than or equal to the specified activation signal (in \(\geq\) x\(_{on}\)), then the relay switches to the enabled position and generates the respective signal value at the output (out = y\(_{on}\));
if the input signal is greater than or equal to the specified tripping signal (in \(\leq\) x\(_{off}\)), then the relay switches to the enabled position and generates the respective signal value at the output (out = y\(_{off}\));
if the input signal is less than the specified activation signal (in < x\(_{on}\)) and more than the specified tripping signal (in > x\(_{off}\)), then a signal equal to the previous relay state is generated at the relay output.

The operation of the block can be described by the following equation (1):

(1)#\[\begin{split}y =\begin{cases}\ y_{on}, & x\geq x_{on}\\y_{off}, & x\leq x_{off} \end{cases}\end{split}\]

where:

\(x_{on}\) – value of input signal at which the relay “turns on”;

\(x_{off}\) – value of input signal at which the relay “turns off”;

\(y_{on}\) – value of output signal at which the relay is “on”;

\(y_{off}\) – value of output signal at which the relay is “off”.

The operation of the block is graphically shown on the static characteristic given in Fig. 1 :

1. Properties#

Property	Default Value	Description	Units of measurement
Value of input signal to activate	1.0	-	-
Value of input signal to trip	0.0	-	-
Value of output signal at enabled state	1.0	-	-
Value of output signal at disabled state	0.0	-	-

Parameters	Input/Output	Description	Units of measurement	Port type
Input signal	Input	Signal	-	Automation
Output signal	Output	Signal	-	Automation

In order to see the connection capabilities of the block, you need to go to page Description of block ports