Cortelco 2740 - Manual (Page 33)

28 2740 User Manual Version 1.11
6.4 Fax Machines and Modems
The line indicators of the 2740 telephones will light when fax machines or modems are using a line.
7. Batteries
The 2740 uses AC power from a standard wall outlet. As long as the telephone is connected to a wall
outlet, it will operate using the AC power. Please remember to plug your telephone into a wall outlet
that is not controlled by a wall switch. The 2740 uses 3 AAA batteries for backup power. These
batteries fit into a compartment on the base of the telephone.
The display has a battery symbol whenever the batteries are low and need replacing or when no
batteries are installed.
7.1 Battery Replacement
a. Make sure the AC cord is attached to the telephone and to a working electrical outlet.
b. Turn the telephone over.
c. Remove desk pedestal/wall mount bracket if attached.
d. Remove battery door cover by using the tip of a ball-point pen, or paper clip, or similar
object to release the battery door tab.
e. Remove the old batteries.
f. Insert 3 new AAA size alkaline batteries. Note that we recommend ONLY alkaline
batteries.
g. Close the battery cover.
7.2 Power Failure Operation
If AC power is disconnected or there is a power failure, the 2740 switches to battery operation for
approximately two hours. When the power is restored, the telephone automatically switches back to AC
power and resumes normal operation.
If the batteries are missing or low on power when AC power is lost, the telephone will not function.
However, all feature settings and memory numbers will be maintained.
Note: It is recommended to always have at least one standard telephone connected, so communications
can be maintained during a power failure.