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Converter Operation Modes
All WFCO power converters are automatic three-stage switching
power supplies. The converter senses which mode it needs to be in by
checking the RV system voltage.
The three modes/stages of operation include:
Absorption mode/Normal operation
Nominal battery charge and supplies power to appliances
Bulk mode/Charge mode
Fast battery charge and supplies power to appliances
Float mode/Trickle charge
Trickle battery charge during storage
Absorption Mode:
During this mode, the converter output is in the
13.6 Vdc range. This is the normal operation mode. This mode
provides the 12 Vdc and current required by the 12 Vdc RV appliances,
as well as slow charging the battery.
Bulk Mode:
In this mode, the output voltage of the converter will
switch to 14.4 Vdc range for a maximum of four hours. If the converter
cycles between “Absorption and Bulk mode”, there could be a shorted
battery cell or other issues.
Float Mode:
In this mode, the converter is charging the battery with a
trickle voltage of 13.2 Vdc. When the converter senses a demand (by
turning on lights), the converter automatically returns to the
“Absorption mode”.
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WF-9900 SERIES
FUSE
FUSE
+VCC
®
Model number
MODEL: WF-89xx
Troubleshooting 9900 Series Power Center
If there is no DC output, first check the reverse polarity fuses on the front
panel of the WF-9900 Series power center. Then, visually inspect the fuses
for any breaks; if none are found, use a continuity tester to check for continuity.
If the reverse polarity fuses are blown, it means the RV battery was accidentally
connected in reverse, either at the battery or at the converter. Reconnect
properly, then replace the fuse with the same type and amp rating as the
original “Littelfuse ” Type 257 automotive-style fuse.
IMPORTANT:
These fuses protect the converter from damage in the event that
the RV battery is accidentally connected in reverse. A reversed battery
connection, even for a second is enough to cause the fuse to blow.
The fuse rating that the RV manufacturer suggests for the output fuses will be
marked on the unit. Replace only with same type and rating.
A
TC style
“Littelfuse ” Type 257 fuse
®
Actual appearance of the front cover may vary.
