Permissible Cable Length - Teletek electronics iRIS8 Installation Manual

4.5.1 Permissible Cable Length

The maximum length of the loop in the system could vary according to the cross-section and the ohmic resistance of the
used cable.
Nevertheless, there is no specific requirement for cable description according to standard EN 54-2, the manufacturer
recommends using the listed cables in installations:
No Brand
1 Mining Ltd Fire cable AF*
BERICA CAVI S.P.A ITALY
2
MULTICORE FLEX SCR
TEKAB FireTEK, SA7Z1,
3
ZA7Z1, MZA7Z1
4 Atron ACFF
5 Atron ACFR
6 Atron PIROFREN SOZ1-K
*This cable is tested and approved.
ATTENTION: iRIS8 TTE loop controller supports up to 250 devices!
To ensure the correct operation of the system is necessary to make some calculations in advance:
1. To ensure the ability of the fire
panel to receive the signals from the
devices in the loop, calculate:
≤ 123 / R
L
C1max
Where:
L , L and L
C1MAX C2MAX C3MAX
R - is total ohmic resistance of the two wires of the used able; its value shows the magnitude of the cable resistance at
C
length 1km [Ω/km];
R - is the total resistance of the isolator modules in the loop;
I
I - is the maximum current consumption in the loop in alarm condition - total amount of the current consumption of all
max
devices in alarm state** in the loop.
Note: In case of using more than 15 devices SensoIRIS series from type T110/ T110 IS, S130/ S130IS, M140/ M140IS,
MCP150 and MC-Z, in calculation of I
15 devices with the highest consumption, and for the rest devices is used the consumption in stand-by mode**.
** For the max. current consumption in alarm state and the consumption in quiescent state with communication (stand-by mode) of a device refer to its
installation manual.
L - is the necessary length of the cable for the loop.
C
After calculating, the maximal length of the cable is determined according:
· ≤ L
If L and L
C C2max C
be able to identify the presence of double address.
· ≤ L
If L < L
C2max C C1max
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 > L or L > L
C C1max C C3max
Parameters
Unscreened, CEI 20/22 II IEC 60332-3, GR2, C-4 (U0=400V) CEI-UNEL-36762,
2x0.8mm 2
Screened, CEI 20/22 II CEI EN 60332-1-2, CL 5 CEI EN 60228 VDE 0295,
300/500V, 2x0.5/0.75/1.0/1.5mm
Screened, C/W BS 6387, Class-1/Class-2 BS 6360, 300/500V, 2x1.0/1.5/2.5mm
Screened, IEC332,2, 2x1.0/1.5/2.5mm
Screened, IEC332,2, 2x0.8mm
Screened, PH90 DIN EN 50200 TS IEC 60331-2, 300/500V, 2x0.8/1.5mm
2. To ensure the ability of the fire
panel to recognize the double
addresses in the system, calculate:
C
- are maximum permissible length of the used cable, [km];
value is used the maximum current consumption in alarm state** only for those
max
≤ L
- the fire panel will be able to communicate with the devices in the loop and also will
C3max
≤ L
and L - the fire panel will be able to communicate with the devices in the loop but
C C3max
- the fire panel would not be able to communicate with the devices.
iRIS8 - Addressable Fire Alarm Panel – Installation Manual
2
2
≤ 62 / R
L
C2max C
21
2
3. To ensure the ability of the devices
in the loop to receive command
signals from the panel, calculate:
≤ (12 / I
L
C3max
2
2
- R ) / R
max i C