7.
Regulated output voltage of 14.2VDC +/ - 1% from the modules ( measured at screw
terminals
S5
and
S6
(Fig.1) is fed to the positive and negative DC bus bars and from
there to the output terminals
LOAD+
and
LOAD-
through the isolating Schottky Di-
ode
D1.
Although the output voltage at the module terminals
S5
and
S6
( Fig.1) or at
the common DC bus bar (before the Schottky Diode
D1
) is tightly regulated at the
preset value of 14.2VDC +/ - 1%, the voltage at the output terminals
Load +
and
Load -
will vary slightly due to the forward voltage drop of the isolating Schottky Di-
ode
D1
and the drop along the DC bus bar and wiring.
The voltage at the output
terminals LOAD + and LOAD – will be as follows :
At no external load
Approx. 14V
At 10 A load
Approx. 13.8V
At loads > 10A
Approx. 13.8V minus 5mV per Amp above 10A
THE BATTERY SHOULD BE LOCATED IN A WELL VEN-
TILATED AREA TO SAFELY DISSIPATE HYDROGEN GAS
PRODUCED DURING THE CHARGING PROCESS.
OPERATION OF BATTERY BACK-UP
WARNING!
D1, D2
SCHOTTKY DIODE: 30V, 180A
R1, R2
POWER RESISTOR: 0.78 OHM, 35W
R
STATIC LOAD RESISTOR: 120 OHM, 5W
FUGURE A.
Please refer to the schematic at fig. A above.
When there is a requirement of un-interrupted D.C. power to the load, an external
battery may be connected at the terminals B and Battery –. When the input
A.C. power is available, the load current is supplied by the power supply through
isolating Schottky Diode
D1
. At the same time, the battery is charged through resis-
tors
R1
&
R2.
(These resistors will limit the maximum charging current to about 8
Amperes.)
