Com Loop Cable Length - Panasonic EBL128 Planning Instructions

Panasonic Electric Works Nordic AB
MEW01090 Rev: 3
18

COM loop cable length

On the COM loop can theoretically 127 COM loop units be connected
(i.e. address 1-127). The cable length is depending on the cable type
(data) and the total COM loop unit current consumption (i.e. the type
and number of loop units).
Figure 34 and Figure 35, page 132 and 133 respectively, shows the
relation between the current consumption and conductor resistance /
cable length respectively.
One of the graphs has to be used depending on which type of units
that are connected to the COM loop. Graph 1 is not used for EBL128.
Start checking the terms below for Graph 2 and then Graph 3.
1. Graph with square dots. Normally not to be used for EBL128.
Used only if "old" conventional smoke detectors requiring > 15 V are
used, i.e. detectors of type 231x/2321 connected to 3361.
2. Graph with circular dots. Used when no "old" conventional
smoke detectors of type 231x/2321 (requiring > 15 V) are used.
Has to be used when at least one 3361 unit with the monitored input
used as a zone line input (Z) is used with conventional detectors
(e.g. 2324 + 4350 / 4352) and an end-of-line capacitor.
3. Graph with no dots (red line). Used when only "new" units
(requiring > 12 V) are used.
Can be used when only the following units are used:
4370 / 4313
3312 + (3308, 4300 or 4301)
3309
3333 / 3339
3361 when the monitored input is not used as a zone line input
(Z)
3364
3366
3377 / 3378 + (3308, 4300 or 4301)
Here follow two figures, showing graphs for maximum conductor
(wire) resistance and maximum cable length respectively.
129
EBL128 Planning Instructions V1.1.x