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
T H O R M O T O R C O A C H | M A D E T O F I T
When the auxiliary battery(ies) have reached a state of
full-charge, the AGS will automatically turn OFF the
generator.
Refer to the manufacturer’s instructions for complete AGS
operating and safety information. Copies are included in your
Owners Packet or on-line through the TMC Owners Resource
document service.
Generator Access
Due to the mounting position of the generator, ground
clearance of the motorhome is restricted. Always be
mindful of road hazards, curbs, speed bumps, and other
road-related issues that could impact and damage the
generator.
If damaged, do not operate the generator until all
repairs are properly performed.
CAUTION CAUTION
The generator is located underneath the vehicle, secured by
mounting brackets. The vehicle must be raised to access the
generator for service or maintenance. Always secure a raised
vehicle with jack stands.
Refer to the vehicle manufacturer’s owner’s manual for proper
jacking procedures.
Automatic Transfer Switch
The transfer switch provides protection from reverse
polarity and ground faults due to faulty shore power
source and generator wiring.
DO NOT DEFEAT THESE PROTECTIVE FEATURES.
SEVERE DAMAGE TO THE ELECTRICAL SYSTEM,
INCLUDING ELECTRICAL SHOCK COULD OCCUR.
WARNING WARNING
The Automatic Transfer Switch is an electronically controlled
relay that senses the presence of 120 volts AC incoming pow-
er; either from shore power or from the on-board generator.
It automatically switches between these two incoming power
sources, connecting the active incoming power source to
the Power Load Center, thereby powering the motorhome’s
electrical system.
When 120 volts AC is not present, the Automatic Transfer
Switch connects the auxiliary battery to the coach 12 volt sys-
tem. If an inverter is installed, limited 120 volts AC is available
for a restricted number of circuits and appliances.
THE AUTOMATIC TRANSFER SWITCH
OPERATES UNDER THESE CONDITIONS:
• When shore power is sensed, it connects the external AC
power source to the Power Load Center.
• If there is a shore power outage and the generator is
started, either manually or by the Automatic Generator
Start System (AGS), incoming power is switched from
the shore power source to the generator after a 20-45
second delay.
• If shore power returns while the generator power is
present, the system remains on generated power until the
generator is turned off. With the generator off, electrical
power for the motorhome is switched to the shore power
source.
• The generator overrides shore power.
• If 120 volts AC is not present, check the circuit break-
ers at the shore power source and/or the output of the
generator.
TRANSFER SWITCH PROTECTION
Beginning with model year 2022, TMC motorhomes are
equipped with transfer switches that provide reverse polarity
and open neutral protection. If there is a fault with the shore
power source, a fault warning message will be displayed on
the multiplex main panel screen. Power will not be passed
through the transfer switch to the motorhome until the fault
is corrected.
IF A FAULT MESSAGE IS DISPLAYED:
1. Contact the park maintenance personnel to check the
wiring of the shore power source. DO NOT ATTEMPT
TO REPAIR A FAULTY SHORE POWER SOURCE.
LEAVE IT TO A PROFESSIONAL ELECTRICIAN.
2. If 120 volts AC is NOT present while attempting to pow-
er your motorhome with the on-board generator, check
the circuit breakers on the generator.
• Turn OFF air conditioner and other electrical
appliances.
• Reset circuit breakers if needed.
• Re-start the generator and after 30 seconds, turn ON elec-
trical appliances. If power is not restored, have a qualified
service technician look into possible problems with the
generator or transfer switch.
NOTE: All TMC Class B motorhomes are equipped
with a transfer switch rated for 30 amp service. Do
not attempt to connect to a higher amperage power
source.