Teletek electronics IRIS - Page 15

Addressable Fire Panel IRIS - Installation and Programming Manual 15
After calculating, the maximal length of the cable is determined according:
· If L
C
≤ L
C2max
and L
C
≤ L
C3max
- the re pane will be able to communicate with the devices in the
loop and also will be able to identify the presence of double address.
· If L
C2max
< L
C
≤ L
C1max
and L
C
≤ L
C3max
- the re panel will be able to communicate with the devices
in the loop but will not be able to identify the presence of double addresses.
ATTENTION:
Always calculate the maximal cable length according the mentioned above formulas!
IF L
C
> L
C1max
or L
C
> L
C3max
- the re panel would not be able to communicate with the devices.
The connection diagram shown on Figure 16, gives the possibility to protect devices against opening and
short-circuit. For example, short-circuit in section 2 will not inuence the operation of sections 1 and 3. The
isolator modules at the both ends of section 2 will isolate it, and section 1 and 3 will continue working properly,
as section 1 will operate by supply from the channel “A” and section 3 - by supply from channel “B”. Since
the re panel will not be able to communicate with the devices from section 2, it will generate an alarm signal
for lost devices and open circuit.
Isolator
module
Section 1
Protected
premises
Isolator
module
Isolator
module
Section 3
Protected
premises
Section 3
Protected premises
Figure 16. Example for connecting of detectors and call points to a loop expander.
The maximum number of devices between two isolator modules is 30!
!
!