Panasonic KX-TD500 Installation Manual page 30

1.6 Specifications
Power Unit
Functions
CPU Card
Functions
Operation
(1) Power supply (+5.9, ±15, GND) for a shelf.
(2) External battery interface. (±12V)
Battery power (±12V) is input from KX-A46 / KX-A46D
(Battery Backup Adaptor) with a 4-wire cable.
(3) Power failure detection.
A circuit in power unit detects power failures of
+5.9VDC, ±15VDC, AC Voltage, and 3 power alarm
signals are sent to CPU card as DC alarm, AC alarm and
Heat alarm.
(4) Generation of bell signal. (25Hz, 75Vrms)
(1) Call process and basic shelf main protocol.
(Microprocessor 80386EX).
Time switch (TSW) control, detection of system clock
alarm, basic shelf power down and expansion shelf power
down alarm, watch dog timer overflow.
(2) System switch interface.
There are Operation Switch (MODE) (10 modes, 0 to 9)
and System Switch (SYSTEM) (10 modes, 0 to 9) on the
CPU rotary switch.
(3) Terminal interface.
CPU card has two RS-232C terminal interfaces.
(1) Operation Switch (MODE) and System Switch (SYS-
TEM) are set by turning with screw driver.
(2) Reset switch is non-lock push switch.
(3) LED for battery alarm lights when voltage of Lithium-
battery becomes too low (less than 2.5V).
(4) LED for watch dog lights when the software is running
away.
System Outline 1-17