SIMPLICITY PLUS INSTALLATION MANUAL
Approved Document No: GLT.MAN-107
PAGE 13
Issue 3.16 Author: NRPJ Date: 21/09/2017
7. ADDRESSABLE LOOP WIRING
The Simplicity Plus 64 and 126 can connect to one addressable loop. Addressable detectors, addressable call points,
addressable loop powered sounders and several other interface units can be connected to this loop. A MAXIMUM OF 64
DEVICES CAN BE CONNECTED TO THE LOOP WHEN POWERED BY THE SIMPLICITY 64 PANEL, AND 126 DEVICES WHEN
POWERED BY THE SIMPLICITY 126 PANEL. The Simplicity Plus 252 panel can connect to one or two loops. A MAXIMUM OF
126 DEVICES CAN BE CONNECTED TO EACH OF THE TWO LOOPS. We recommend that the first and last devices on a loop
have isolator bases fitted. Also the last device on each zone should have an isolator fitted. This is to prevent a short circuit
fault in one zone affecting another zone.
Note that some Devices (for example, a sounder controller circuit) may require a separate 24 volt supply to operate.
A maximum of 32 loop-powered addressable sounders or sounder bases are permitted on a loop.
Short circuit isolators should be used to prevent losing the whole loop in the event of a single short circuit fault. They
should be fitted to each zone boundary, such that any short circuit will only affect the devices in 1 zone.
The termination of each wiring circuit must be as indicated on the main PCB (See Fig 6). The Earthing of the cable screens
should be as shown in Fig 6.
Pre-Commissioning Cable Checks
+ve in to +ve out less than 24 ohms.
-ve in to -ve out less than 24 ohms (may need to temporarily disable isolators to measure).
+ve to –ve greater than 500k ohm.
+ve to Earth greater than 1M ohm.
-ve to Earth greater than 1M ohm.
+ve to –ve less than 50 mV pickup (on AC & DC scales).
