Sub fip monitoring, General, Sub fip monitoring -19 – Tyco F3200 User Manual

Page 189: 3 sub fip monitoring

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Document No: LT0122

F3200 Installation & Programming Manual

Applications

Issue 2.7

5 July 2001

Page 9-19

9.3

SUB FIP MONITORING

9.3.1 GENERAL

A sub-FIP is a Fire Indicator Panel (e.g. a Gas Flood Panel) which may not be connected

directly to the Brigade, but repeats its common conditions (e.g. Fire, Fault) to another FIP.

AS1670.1 allows for the cabling from FIP to sub-FIP to be less than 0.75sqmm, and the

resistance may be considerably greater than that used in standard detector circuits. The

"Low Current Mode" for an F3200 AZC allows supervision of sub-FIPs on circuits with high

resistance.

The limitations caused by the resistance in sub-FIP monitoring circuits are shown in the

following 3 cases.

1.

Loop Resistance Less than 150 Ohms

For a detector circuit programmed for standard mode the maximum loop resistance is 50

Ohms, but where there is no detector load (i.e. clean contacts are used) the resistance may

be up to 150 Ohms.

Therefore it is recommended that for loop circuits of less than 150 Ohms, "standard mode"

be used for sub-FIP monitoring.

All voltage bands are potentially usable, but it is recommended that B3 NOT be used for any

condition as the circuit voltage drop of up to 2.5V needs to be allowed for. B2 can be used

with a 5V6 or 6V8 zener diode to detect Alarm i.e. ZnA, and B1 can be used to detect Alarm

(ZnD) or Instant Alarm (ZnM).

2.

Loop Resistance of 150 Ohm to 800 Ohm

For this resistance range the AZC has to be programmed into "Low Current Mode", and

voltage band B1 should be programmed as Fault or Alarm but must not be used to detect

the Fault signal from the sub-FIP (i.e. by shorting the circuit with the Fault contacts).

Shorting the circuit at the sub-FIP will cause B2 Alarm.

Because the voltage drop in the circuit wiring is between 3.8V and 12V, depending on loop

resistance, it is recommended that B3 not be used to detect a signal (for safety sake it is

advisable to program B3 as Alarm and B1 as Alarm or Fault. Note that only a short

somewhere within the circuit wiring can cause B1).

3.

Loop Resistance of 800 Ohm to 2000 Ohm

For this resistance range the AZC has to be programmed into "low current mode", and the

voltage band B3 has to be programmed as Alarm. Shorting the circuit at the sub-FIP will

cause either a B2 or B3 Alarm depending on the loop resistance (nominal B2/B3 threshold is

1100 Ohm).

B1 may be programmed as Fault or Alarm, but must not be used to detect the Fault signal

from the sub-FIP.

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