Inverter Applications; Resistive Loads; Motor Loads - Xantrex Freedom EX 4000 Owner's Manual

Inverter Applications

The Freedom EX 4000 performs differently depending on the AC
loads connected to it. If you are having problems with any of your
loads, read this section.

Resistive Loads

These are the loads that the inverter/charger/converter finds the
simplest and most efficient to drive. Voltage and current are in
phase (that is, in step with one another). Resistive loads usually
generate heat in order to accomplish their tasks. Toasters, coffee
pots, and heater elements are typical resistive loads. It is usually
impractical to run larger resistive loads—such as electric stoves
and water heaters—from an inverter due to their high current
requirements. Even though the inverter/charger/converter can
most likely accommodate the load, the size of battery bank
required would be impractical if the load is to be run for long
periods.
975-0999-01-01

Motor Loads

Induction motors (that is, motors without brushes) require two to
six times their running current on start up. The most demanding
are those that start under load, for example, compressors and
pumps. Of the capacitor start motors (typical in drill presses, band
saws, etc.), the largest you can expect to run is 1.25 hp (the
transfer relays are rated at 3 hp). Universal motors are generally
easier to start. Since motor characteristics vary, only testing will
determine whether a specific load can be started and how long it
can be run.
If a motor fails to start within a few seconds or loses power after
running for a time, it should be turned off. When the
inverter/charger/converter attempts to start a load that is greater
than it can handle, it will turn itself off after a few seconds.
Long Transfer Times
The Freedom EX 4000 may take a long time (~ 0.1–0.2 s) to
transfer to Battery Mode when shore power is cut off while
powering a motor load. Motor loads typically "freewheel" when
power is removed (for example, a grinder) and causes a longer
transfer time. The longer transition from shore power to inverter
power may cause connected computers or other sensitive
equipment to operate incorrectly. To avoid this effect, do not
connect motor loads together with sensitive equipment to the
inverter/charger/converter for power.

Inverter Applications

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