Power Supply Per Interface; Power Supply Per Terminal Interface - Mitel 470 System Manual

Overload shutdown
If 80% of the available power output is exceeded, the event message
supply overload is generated.
If 100% of the available power output is exceeded, the event message
supply shutdown is generated. The power supply is then shut down step by step, start-
ing with the expansion slots with the highest numbers and, within the cards, with the
ports with the highest numbers. The terminal ports (FXS, DSI, BRI-S) are shut down in
groups of 4 ports. The exchange ports (PRI, BRI-T, FXO) are never shut down.
Once the power required drops below 100% as a result of the shutdowns, the discon-
nected ports are reconnected after approx. 10 seconds. If the limit of 100% is again ex-
ceeded, the overload shutdown is triggered once again.
The overload shutdown works in principle for all three types of power supply (see
Tab. 35). However it triggers particularly in cases where only the internal power supply
unit is available and a large number of terminals are operated without their own power
supply.
If an overload occurs, either reduce the required supply power (e.g. by powering DECT
radio units and or system phones locally) or use the external auxiliary power supply
unit for terminals.
3. 4. 10. 2

Power supply per interface

DSI interface card
The maximal available power supply on the DSI ports per interface is limited. In certain
cases (e.g. 32 connected SB-4+ radio units with HW version " - 2" at a 32DSI interface
during simultaneously high traffic load) this value can be exceeded and the the over-
load shutdown is triggered. To provide remedy individual terminals must either be pow-
ered locally or spread out on several DSI interface cards.
Tab. 38 Maximal power supply per interface card
Maximal power supply per interface card
DSI interface card
3. 4. 10. 3

Power supply per terminal interface

The power supply per terminal interface is determined by the interface type. The inter-
face load depends on the following variables:
• Terminals used incl. auxiliary devices
• Bus configuration
• Line length and conductor cross-section
For information on the calculations refer to "Terminal interfaces", page 127.
Mitel 470 as of R4.1
syd-0585/1.2 – R4.1 – 08.2016
Expansion Stages and System Capacity
Output P [W]
41.5
Terminal power
Terminal power
91