HEIDENHAIN TNC 407 (243 020) Service Manual - Manual (Page 49)

Kundendienst
SERVICE MANUAL TNC
Issue:
01.09.1995
Page 42
8.7 Buffer Battery
Exchange Buffer Battery
The buffer battery is the voltage source for the
program memory, if the machine tool is switched off.
If the error message
EXCHANGE BUFFER
appears, the batteries must be exchanged within one
week.
The buffer batteries are located behind a screw
fitting in the power supply of the LE
415.
To exchange, open the LE by undoing both snaps
In order to protect the program memory of the
TNC 407, a capacitor (located on the processor board)
is used in addition to the batteries. Thus, the line
voltage may be switched off during battery exchange,
Without the batteries the capacitor is capable of
maintaining the memory contents for about one day.
The TNC contains an additional accumulator so that
without the batteries the memory contents
stored for approx. two weeks.
3 AA-size batteries,
leak-proof
IEC designation
NOTE:
The capacitor and the accumulator are only being
charged when the TNC is switched on (charging
time of the accumulator: approx. 24 hi.
Processor
Board TNC 407 Processor Board TNC 415