Controladores lógicos programables PLC baja gama expandibles entradas digitales AC 74368-SR22MRDC ARRAY Manual Ingles www.viaindustrial.com
Controladores lógicos programables PLC baja gama expandibles entradas digitales AC 74368-SR22MRDC ARRAY Manual Ingles www.viaindustrial.com
3.2.2 TOFD
Line diagram/ Symbol in
SR
Pin Description
Input TRG
Turn on the timer of the time-delay off relay, when the input TRG
(trigger) is at the descending edge (changing from 1 to 0).
Input R
The timer of disconnecting time-delay relay is reset via R (Reset
Input), and Output Q is set to 0. (R has higher priority to TRG.)
Parameter T
The output is disconnected (the Q status is changed from 1 to 0), when
the time T elapses.
Output Q
Input TRG is activated then the output is turned on (Q=1) and is kept
ON until it is reset when the set time T is up.
Output P
If the property pin of the output P is connected with the properties pin
of the SLCD, the parameter of this function block will be transferred
to HMI.
Time Sequence Frame:
Function description:
1. When Input TRG is Status 1, Output Q is changed at once to Status 1. When
Input TRG is changed from 1 to 0 (when the descending edge comes), the
internal time delay timer of FAB is activated and Output Q is still remained in
status 1. When the set time T is up, Output Q becomes 0 and the timer is reset 1.
2. If Input TRG changes from Status 1 to Status 0 again, the timer is activated
again.
3. Before the set time T is up, the timer and output can be reset via R (Reset) input
4. This function is applicable to the lighting of staircase, the control of barriers in a
car park, the control of a water throttling valve, etc.
5. The assignment range of T is 0.01-99.99, and the time units can be set
respectively to hour (H), minute (M), second (S).
6. TRG and R terminals are treated as Status 0 if they are set as X..
