Operation of output logic zone commands, Example equations – Tyco F3200 User Manual

Page 133

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Document No: LT0122

F3200 Installation & Programming Manual

Programming System Configuration

Issue 2.7

5 July 2001

Page 7-31

7.4.9.2

OPERATION OF OUTPUT LOGIC ZONE COMMANDS

Reset Command

A single zone or a range of zones may be reset. All zones in the specified range will be

reset, regardless of whether they are in alarm or not, as if the zones had been reset by an

operator from the keypad.

The output logic initiates the reset command whenever the equation on the right hand side is

true. If the equation is still true at the end of the reset then another reset will be immediately

initiated, and this will repeat until the equation becomes false. Therefore, to avoid repeated

resets the equation should be arranged so that it becomes false before the end of the reset.

The equation needs to be true for only one pass of the output logic for the zone reset to be

initiated.

Isolate / Deisolate Commands

A single zone or a range of zones may be isolated/deisolated. The command will be applied

to all zones in the specified range regardless of the type of zone.

Whenever the right hand side of the equation is true, the zones will immediately be

isolated/deisolated if they are not already isolated/ deisolated.

If an equation to isolate/deisolate a zone is continually true, and an operator enters the

opposite command using the LCD/keypad, then the zone will briefly change but will quickly

revert back due to the output logic.

Therefore the logic equation should be arranged so that the equation is only true for a brief

time or on a change of state. The NA operator may be used for this purpose.

7.4.9.3 EXAMPLE

EQUATIONS

(i)

The equation ZI3:7=BLI will cause zones 3 to 7 (inclusive) to be isolated whenever

BLI is true, i.e. the bells are isolated. If the operator manually deisolates any of

zones 3 to 7 then the output logic will immediately isolate them again if BLI is true.

(ii)

An external switch is used to isolate or deisolate a group of zones. The equation

ZI5:8=Z16M will result in zones 5, 6, 7 and 8 being isolated when zone 16 (the

switch) is in a short circuit state. If it is necessary to deisolate the zones again when

zone 16 is taken out of short circuit then a second equation is needed, perhaps

ZD5:8=^Z16M.

However, including these two equations would prevent an operator from isolating or

deisolating the zones using the keypad because one or other of the two equations

(whichever has a TRUE "right hand side") is continually attempting to isolate or

deisolate the zones. An "NA" function can be used to overcome this as follows.

V1=NA(V1;Z16M)

V2=^Z16M

V3=NA(V3;V2)

ZI5:8=V1

ZD5:8=V3

The output logic will isolate/deisolate the zones only when a transition of zone 16

into/out of the short circuit state occurs. Only one of variables V1 or V3 is true for

exactly one complete pass of the output logic after a transition of zone 16.

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