Energy Management System (Ems); Circuit Protection; Operation - Airstream Interstate 24X Owner's Manual

Energy Management System (EMS)

The Energy Management System is located in the
overhead compartment, behind the driver's seat� A
complete, detailed EMS manual is included with your
owner's packet�
The ENERGY MANAGEMENT SYSTEM controls 120-
volt operated circuits to help keep the total 120-volt
current draw to less than 30 amps� When operating
on generator power the 120-volt draw will be less than
20 amps� These circuits may be any type load, but
are typically heavier loads, those whose use can be
"postponed" until a time when current is available for
their use�

Circuit Protection

Circuit protection for ALL 120 VAC loads are standard
residential resettable circuit breakers installed in the
power center (120 VAC section)� Airstream has pre-
installed the correct breakers per RVIA (NEC) listing
requirements for the touring coach� The MAIN breaker
for the touring coach is 30 amps and feeds the branch-
breakers in the breaker box� Shutting off the MAIN
breaker will remove power to all branch loads, except
for receptacles on the Inverter circuit when the inverter
is "ENABLED"� The Inverter/converter contains a
resettable 20 amp input breaker and a 20 amp output
breaker� The remaining power center branch-breakers
feed individual loads and are defined by the label
affixed next to the breakers. The source for 120 VAC
power to the power center can come from either the
shoreline plug, when connected to a camp site, or the
touring coach's generator, when running� If plugged
into shoreline power, and the generator is started, the
power feed to the power center will be coming from the
generator�
2022 Interstate 24X
The main and general load branch-breakers are
operated similar to a light switch with up as "ON" and
down as "OFF"� If an overload condition or a short
occurs the switch will snap to the "OFF" position�
The load for this breaker will now be "OFF"� Before
resetting the breaker be aware of any device that may
have been plugged in or turned "ON" which may have
cause the breaker to overload� Unplug or turn "OFF"
the possibly faulty device before resetting the breaker�
To reset the breaker, you will need external AC power
going to the breaker box (shoreline or generator),
then firmly push the breaker switch to the "OFF"
position then back to the "ON" position� If the breaker
snaps back to the "OFF" position while resetting, a
fault condition still exists and should be serviced by a
qualified Service Technician. If the breaker stays "ON"
but snaps back to "OFF" after plugging in or turning
ON the possibly faulty device a fault condition may
exist in that device and should be service by a qualified
Technician�
The power center Ground Fault Circuit Interrupter
(GFCI) breaker is a special breaker that will provide
additional safety to the occupants of the touring coach
on the following receptacles; external, galley, lavatory,
and entertainment� In addition to short circuit and
overload protection, the GFCI will shut off the breaker if
any current feeding out of the breaker does not return
to it� As in the case of a person contacting the electrical
energized part of the GFCI circuit and an electrically
conductive object not associated with the circuit�
Refer to Ground Fault Circuit Interrupter and GFCI
Breaker Test in this section for more information�

Operation

In operation, when 120 VAC and 12 VDC are initially
applied, the system will energize the relays at one
second intervals, closing the normally open contacts on
each of the relays while monitoring the total current� If
the total should exceed the service limit, the system will
turn off the last load that was turned on� As it does this,
it calculates the amount of current that was removed,
which is the value for that load� This value is placed
in memory� The system has "learned" the amount of
current that particular appliance draws� This feature
compensates for the difference in current draw over
a range of line voltage and ambient temperature, by
relearning the load each time it is turned off�
The system now waits until the total current is lower
than the service limit, by the amount in memory, before
it will turn that load back on� This ensures that there is
sufficient current to operate the load.
Interior
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