LI-3000 / LI-3000E
© 1999
–
2015 Telefire Fire & Gas Detectors Ltd
Revision 1.14 May 2015
– Page 1 of 6 –
1
Introduction
The LI-3000 and LI-3000E short-circuit line isolators are intended for use in the signaling
line circuit (SLC) of Telefire's addressable control panels.
The devices are connected to and powered by the SLC and are used to protect against
short circuit by disconnecting the short circuit from the rest of the SLC.
The LI-3000 requires an address that is set by the PROG-4000 device programmer.
The LI-3000 and LI-3000E enable wiring the SLC Loop in a closed loop (NFPA Style 6
Class A) as well as branching T-shaped (NFPA Style 4 Class B) wiring configuration.
Class A configuration does not reduce system capacity. To establish an NFPA Style 6
Class A loop in an ADR-3000 requires a minimum of 3 LI-3000 per loop.
Each SLC Loop is capable of addressing 127 devices, including the addresses occupied
by the LI-3000 modules. A single-loop line card that is configured as Class A can
address up to 127 addresses (including LI-3000 line isolators), and a dual-loop line card
can address up to 254 addresses (including LI-3000 line isolators) in two Class A loops.
2
Compatibility
The LI-3000 and LI-3000E are compatible with the full range of Telefire's addressable
control panels and addressable devices.
3
Application
3.1
Characteristics
After power up or reset of the system, the isolator checks for short-circuit condition. If no
short-circuit is detected the isolator switches the circuit on and enables normal operation
of the second connection of the SLC Loop.
Whenever a short-circuit condition occurs the Isolator opens the circuit automatically and
disconnects the faulty side of the loop. Three seconds later it resets and performs a
second test, and then again a minute later. It repeats the test for eight minutes, and
then periodically it will re-test every two minutes. The test cycle restarts when the
module is reset.
The yellow LED flashes each time the module is addressed by the control panel. A
short-circuit condition will cause the LED of the shorted side to latch on.
An open circuit in a Class A configuration will send a trouble message to the control
panel. The LI-3000 will latch on the LED corresponding to the open side.
As many as 20 Isolator modules can be installed in each SLC Loop.
3.2
Class A Configuration
Configuring a loop as Class A does not reduce loop capacity, other than the addresses
used by the short circuit line isolators themselves – each loop is still able to work with
127 addresses.
i
Note
Short circuit line isolators model LI-3000 have an address and report of a
disconnection on one of the sides to the control panel.
LI-3000E line isolators do not have an address. The control panel will report
missing devices in case of disconnection.