Pertronic Analogue Addressable Loop Length Calculator

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Items
No of units
Unit Current
Total Quiescent Current
Apartment Module
Units
Unit Current
7mA
Tot. Quiescent Current
0mA
Loop Relay
Units
Unit Current
6mA
Tot. Quiescent Current
0mA
Loop Responder (Loop Powered)
Units
Unit Current
27mA
Tot. Quiescent Current
0mA
Loop Responder (Ext Powered)
Units
Unit Current
7mA
Tot. Quiescent Current
0mA
Conventional Smoke Detectors ++
Units
Unit Current
0.05mA
Tot. Quiescent Current
0mA
Analogue Modules
Units
Unit Current
0.35mA
Tot. Quiescent Current
0mA
Analogue Detectors (F100A = 99 max)
Units
Unit Current
0.35mA
Tot. Quiescent Current
0mA
Isolate Timer Module
Units
Unit Current
10mA
Tot. Quiescent Current
0mA
PS2 Sounder 24V
Units
Unit Current
0.004mA
Tot. Quiescent Current
0mA
Fan Controller, Fan Relay
Units
Unit Current
15mA
Tot. Quiescent Current
0mA
PSB Sounder (F100A = 99 max)
Units
Unit Current
1.5mA
Tot. Quiescent Current
0mA
WST-XX-N Wall Mount Strobe
Units
Unit Current
0.45mA
Tot. Quiescent Current
0mA
6500S Analogue Beam
Units
Unit Current
2mA
Tot. Quiescent Current
0mA
Enter alarm current in mA.
(1 detector = 6.5 mA)
Total Current = TQmax
Load OK
65 mA
Twisted Pair Cable Size mm2
Maximum Loop Current: MUST NOT Exceed
350 mA
Minimum Panel Loop Voltage
22.8 Volts
Minimum Working Loop Voltage
15 Volts
Maximum Loop Volt Drop = VD
7.8 Volts
Cable Resistance Ω/m
0.01584 Ω/m
Maximum Allowable Loop Cable Resistance, Load Spread Evenly = 2 x (VD/TQmax) **
50 Ω
Maximum Allowable Loop Cable Resistance, Load at end = VD/TQmax **
50 Ω
Maximum Cable Loop Length Must Not Exceed
2500 Meters
Maximum Loop Length (m) - Load Spread Evenly Over Loop
2500 Meters
Maximum Loop Length (m) - Load at end of Loop
2500 Meters
** To measure Analogue Loop Cable Resistance:
a) short the cable pair at one end.
b) bypass all isolators to ensure continuity (link +ve in to +ve out).
c) measure the resistance across the two conductors - red to black.
++ Include only Conventional Smoke Detectors connected to Loop
     Powered Interfaces such as Loop Responders.
Loop Calculator
65mA
65mA
2500mA
2500mA