User's Manual

Chapter 3: Installation requirements
This chapter provides information about power supplies, cables, grounding and environmental and space
requirements for installing the B5800 Branch Gateway control unit and external expansion modules. The
B5800 Branch Gateway control unit can be mounted on the wall if no external expansion units are included
in the installation. If the installation includes external expansion modules, the control unit and external
expansion modules can be mounted into a standard 19-inch rack system.
Power supply backup (UPS)
The use of an Uninterrupted Power Supply (UPS) with any telephone system is strongly
recommended. Even at sites that rarely lose electrical power, that power may occasionally
have to be switched off for maintenance of other equipment. In addition, most UPSs also
provide an element of power conditioning, reducing spikes and surges.
The capacity of UPS systems and the total equipment load the UPS is expected to support are
usually quoted in VA. Where equipment load is quoted in Watts, multiply by 1.4 to get the VA
load.
The calculation of how much UPS capacity is required depends on several choices.
• What equipment to place on the UPS? Remember to include server PCs such as the
voicemail. It is recommended that the total load on a new UPS is never greater than 75%
capacity, thus allowing for future equipment.
• How many minutes of UPS support is required? Actual UPS runtime is variable, it
depends on what percentage of the UPSs capacity the total equipment load represents.
For example, a 1000VA capacity UPS may only support a 1000VA (100%) load for 5
minutes. This relationship is not linear, the same UPS would support a 500VA (50%) load
for 16 minutes. Therefore the lower the percentage of capacity used, the increasingly
longer the UPS runtime, typically up to 8 hours maximum. Remember also that for most
UPS's the ratio of discharge to full recharge time is 1:10.
• How many output sockets does the UPS provide? Multiple UPS units may be required
to ensure that every item of supported equipment has its own supply socket.
The web site
http://www.avayaups.com provides a calculator into which you can enter the
equipment you want supported on a UPS. It will then display various UPS options. The site
uses VA values for typical B5800 Branch Gateway systems. However, if more specific values
are required for a particular system, the table below can be used to enter values.
Implementing the Avaya B5800 Branch Gateway November 2011 35