7SR11 & 7SR12 Description Of Operation
ยฉ2017 Siemens Protection Devices Limited Chapter 1 Page 71 of 88
4.4 Quick Logic
The โQuick Logicโ feature allows the user to input up to 4 logic equations (E1 to E4) in text format. Equations can
be entered using Reydisp or at the relay fascia.
Each logic equation is built up from text representing control characters. Each can be up to 20 characters long.
Allowable characters are:
0, 1, 2, 3, 4, 5, 6, 7, 8, 9 Digit
( ) Parenthesis
! โNOTโ Function
. โANDโ Function
^ โEXCLUSIVE ORโ Function
+ โORโ Function
En Equation (number)
In Binary Input (number)
โ1โ = Input energised, โ0โ = Input de-energised
Ln LED (number)
โ1โ = LED energised, โ0โ = LED de-energised
On Binary output (number)
โ1โ = Output energised, โ0โ = Output de-energised
Vn Virtual Input/Output (number)
โ1โ = Virtual I/O energised, โ0โ = Virtual I/O de-energised
Example Showing Use of Nomenclature
E1= ((I1^V1).!O2)+L1
Equation 1 = ((Binary Input 1 XOR Virtual I/O 1) AND NOT Binary Output 2) OR LED 1
When the equation is satisfied (=1) it is routed through a pick-up timer (En Pickup Delay), a drop-off timer (En
Dropoff Delay), and a counter which instantaneously picks up and increments towards its target (En Counter
Target).
The counter will either maintain its count value En Counter Reset Mode = OFF, or reset after a time delay:
En Counter Reset Mode = Single Shot: The En Counter Reset Time is started only when the counter
is first incremented (i.e. counter value = 1) and not for subsequent counter operations. Where En
Counter Reset Time elapses and the count value has not reached its target the count value is reset to
zero.
En Counter Reset Mode = Multi Shot: The En Counter Reset Time is started each time the counter is
incremented. Where En Counter Reset Time elapses without further count increments the count value
is reset to zero.