19.3 Operation - Motorola R-20010 Maintenance Manual

19.3 OPERATION
The battery pack is automatically engaged when no
ac power is present, and when the POWER switch is
set at either ON or STANDBY. When ac power is
applied, the Analyzer automatically switches the bat-
tery pack out of the circuit and draws its power from
the ac power source.
When the POWER switch is set at OFF or
STANDBY, and ac power is applied to the System
Analyzer, the battery pack draws de current from the
Analyzer to activate the charging circuit. The charg-
ing circuit delivers approximately 750 rnA of current
until the battery voltage reaches 14V. As the battery
voltage reaches 14V, the current drops to approxi-
mately 25 rnA, and the high-charge indicator LED goes
out .
T o extend the time the battery can operate the Sys-
tem Analyzer, keep the unit's POWER switch set at
STANDBY whenever possible. Because of the low
II:S
610
PI-:S IIU>-WHT
trickle-charge rate, the batteries can be left charging
indefinitely without damage from overcharging.
At high ambient temperature, if you plan to operate
the Analyzer from the ac line for long periods of time,
remove the battery pack and reinstall the blower
assembly.
R7
10 K
CAUTION
Do NOT permit battery dis-
charge below 10.4 Vdc (as indi-
cated on the CRT in DVM
display mode); immediately turn
the unit OFF. Allowing battery
discharge below this level may
permanently damage the battery.
To recharge the batteries, plug
the System Analy zer into ac
power ( 117/234 Vac) with the
POWER switch set at OFF or
STANDBY.
*
Ill I'-"-~._..._~ 2K
L _ _ _ _ _ _ J
119
..
9.:.;-~ f K:.;..._
____________________ _ : B .:,L:;_K -<.PI-
4
* WITH THE BATTERIES REMOVED IBT1 AND BT2)
AND A 30-0HM; 10 WATT RESISTOR IN PLACE
OF THE BATTERIES. SET RB FOR 14.45V
z
SOMV USING
A DIGITAL VOLTMETER ACROSS THE BATTERY
TERMINALS.
Figure 19-2. Battery Pack - Schematic
19-2
36930-131