P/N PM000223A • Rev. 1 • ISS 9 August 2017
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Installation Manual
NU-Series Hardware
System Power
3.1.3 teleCARE M Power Supply Wiring
It is important to use the correct wire sizes and to consider the length of the 24V power
supply wires. The minimum acceptable wire size of the 24V bus is 1mmØ (0.8mm²).
Note: Excessive 24V bus length can result in unacceptable voltage drop. The lowest
acceptable voltage at any point in the 24VDC distribution is 21.6VDC.
For the stub wiring between the 24VDC bus and the control module wire size 1mmØ
(0.8mm²) must be used.
Warning: Incorrect wire size can result in dangerous overheating of the wires.
Note: The NU-series devices cannot be used with 24VDC power as this will
damage the devices.
The output of the power supply unit can be divided over multiple buses. This method is
recommended as it will reduce the power cable lengths.
Figure 22 24V/4.2A Power
3.1.4 Power Supply Basic Installation
The 24VDC power is carried on a two-wire cable that loops from NUPBC to NUPBC. The
minimum wire size for the 24VDC power supply bus is 18 AWG (1mm).
Figure 23. LAN and room bus cables with power supply (24VDC)
3.2
Hallway Power Supply
The Gateway II provides power to the devices on the hallway bus. This is 36VDC with up
to 100W power per hallway bus. The hallway bus should not exceed 300m(1000ft). The
lowest acceptable voltage at any point on a fully loaded hallway bus shall be no less than
24VDC.
