Thor Motor Coach CLASS B, Owner'S Manual

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E L E C T R I C A L S Y S T E M
C U S T O M E R C A R E | 8 7 7 . 8 5 5 . 2 8 6 7
Converter
The power converter is
a 12 volt power supply,
which provides 12 volts
DC from incoming 120
volts AC, either sup-
plied from an external
shore power source
or the on-board gen-
erator. The converter
also provides charging
energy for the auxiliary
battery(ies). The con-
verter is typically housed
within the power load center of 30 Ampere electrical systems,
but it can be a stand-alone unit in some applications.
The converter has a built-in protective thermal breaker that
will shut it down should overheating occur. Overheating can
be caused by operating the converter above its maximum
power output for an extended period of time, or by an
obstruction to its ventilation air flow.
CONVERTER OPERATION MODES:
Most converters are automatic three-stage switching power
supplies. The converter senses which mode it needs to be in
by sensing the demands of the motorhome's power demand.
• Absorption mode/Normal operation: During this mode,
the converter output is in the 13.6 volts, DC range. This
is the normal operation mode. This mode provides the
12 volts DC and current required by the 12 volt lighting,
appliances, and devices; well as slow charging the auxil-
iary battery(ies).
• Bulk mode/Charge mode: In this mode, the output volt-
age of the converter will switch to 14.4 volts DC range
for a maximum of four hours. This mode provides extra
energy for faster auxiliary battery charging. If the con-
verter cycles between 'Absorption and Bulk mode', there
could be a shorted battery cell or other issues.
• Float mode/Trickle charge: In this mode, the converter
is charging the battery with a trickle voltage of 13.2 volts
DC. When the converter senses a demand (by turning on
lights or other 12 volt devices), the converter automati-
cally returns to the 'Absorption mode.'
NOTE: The master battery disconnect switch must
be ON for charging energy from the converter to
connect to the auxiliary batteries.
Typical converter: model, features, and
installation location varies, depending
on motorhome model and floorplan.
USING THE CONVERTER
Under normal operating conditions, the converter requires no
user attention or maintenance. However, if the coach batteries
happen to become reverse connected, fuses that protect the
converter from cross-polarization may blow. If your convert-
er is not operating, check the polarity of the coach battery
connections and correct if necessary. If the fuses on the front
panel of the converter have blown, replace with the same type
and amperage rating. If the incoming AC voltages are normal,
but the converter output is still not delivering 12 volts DC,
the converter requires repair. Contact the manufacturer for
service details.
Due to the high level of electrical energy it supplies, the con-
verter may be warm to the touch when operational, and this
is normal. It does, however, have built-in thermal protection;
if it gets too hot, it will turn itself off. After it cools down, the
converter will return to normal operation. In most cases, this
thermal cycling is caused by some object being placed in too
close of proximity to the converter, preventing it from receiv-
ing adequate ventilation. Make sure not to place anything near
the converter that could obstruct ventilation.
INSPECTION AND MAINTENANCE
If the power converter is not working check the fuse(s) located
on the outer case. There are no customer serviceable parts
inside the converter case and the manufacturer’s warranty
will be voided if the case has been opened. If you have further
concerns please contact your selling dealer.
If the converter is not operating correctly, the reverse
polarity protection fuse may be blown (located on
the converter front panel). Check the connections
on the coach battery for proper polarity and correct if
necessary. If a fuse requires replacement, only replace
with one of the same type and rating.
NOTICE NOTICE