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Flowire Converter Configuration Manual
A100K11422
Conventional star-wired telecom infrastructures commonly use one twisted wire pair to each telecom
device. However, many systems, like AlphaCom, use two twisted pairs for each telecom device
2.2 Power on Conventional Infrastructure
In an analog and digital telecom/intercom system, it is usually a requirement to power the telephones/
intercoms from the central equipment rack, thus supplying the power over the subscriber line.
Typical maximum subscriber line distances for intercom systems are:
Wire cross section
Distance
0.6 mm
2
(19 AWG)
2.0 km
0.5 mm
2
(20 AWG)
1.4 km
Table 1 AlphaCom Subscriber Line Distance
Wire cross section
Distance
0.5 mm
2
(20 AWG)
0.8 km
Table 2 AsaCom Subscriber Line Distance
2.3 Precaution & Limitations
● The cable shields must be interconnected in junction boxes and grounded in the central device
only.
● Never use a cable run where the voltage drops below half of the PSU voltage.
● Do not connect more than 10 Flowire Converters on one Flowire star configuration.
● Powering of remote IP intercom stations through their Ethernet ports requires at least 40 VDC
at the remote site.
2.4 Recommendations
● Use twisted-pair shielded cables
● The cable between the PSU and the Flowire Converter should not be shorter than 50 cm.
● Unless the cables are shielded, you should avoid running wires from different Flowire star
configurations in the same cable ducts.
● Avoid multi-pair cables with connections to other systems.
● If you are using a multi-pair cable, but not all its pairs, connect more pairs between two Flowire
Converters to reduce voltage drop and increase bandwidth.
● In a central rack with two or more Flowire Converters in close proximity, use heat shrink with
grounding on unshielded areas of the cable to isolate the different Flowire star configurations
and avoid cross-talk.
