Inductive Loads; Low Battery Dropout; Problem Loads - Xantrex RV2012GS Owner's Manual

Operation

Inductive Loads

Low Battery Dropout

Problem Loads

3–4
Any device that has a coil of wire in it probably has an inductive load
characteristic. Most electronics have transformers (TVs, and stereos, for example)
and are therefore inductive. Typically, the most inductive loads are motors. The
most difficult load for the inverter to drive will be the largest motor you manage to
start. With inductive loads, the rise in voltage applied to the load is not
accompanied by a simultaneous rise in current. The current is delayed. The length
of the delay is a measure of inductance. The current makes up for its slow start by
continuing to flow after the inverter stops delivering a voltage signal. How the
inverter handles current that is delivered to it while it is essentially "turned off"
affects its efficiency and "friendliness" with inductive loads. The best place for
this out-of-phase current is in the load, and the RV Series Inverter/Charger's
impulse phase correction circuitry routes it there.
Inductive loads, by their nature, require more current to operate than a resistive
load of the same wattage rating, regardless of whether power is being supplied by
an inverter, a generator or grid. An air conditioner is a common inductive load in
an RV.
Induction motors (motors without brushes) require two to six times their running
current on startup. The most demanding are those that start under load, such as
compressors and pumps. Of the capacitor start motors, typical in drill presses and
band saws, the largest you may expect to run is ½ to 1 hp. Universal motors are
generally easier to start. Since motor characteristics vary, only testing will
determine if a specific load can be started and how long it can be run.
If a motor fails to start within a few seconds, or it begins to lose power after
running for a time, it should be turned off. When the inverter attempts to start a
load that is greater than it can handle, it will turn itself off after about 10 seconds.
The inverter will turn off to protect itself if your battery bank cannot deliver the
necessary amperage to drive a particular load without falling below the low
voltage protection point (10.5 V) for three seconds. With the inverter off, the
battery voltage will rise and then it will resume operation.
Xantrex inverters can drive nearly every type of load. However, there are special
situations in which inverter power may behave differently than utility power.
Very small loads If the power consumed by a device is less than the threshold
of the search mode circuitry, it will not run. This can usually be solved by
plugging in an additional load such as a 100-watt light bulb.
Fluorescent lights and power supplies Some devices when scanned by the
load sensor cannot be detected. Small fluorescent lights are the most common
example. (Try altering the plug polarity by turning the plug over.) Some
computers and sophisticated electronics have power supplies that do not present a
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