Inverter Applications
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Freedom X Owner's Guide
Inverter Applications
The Freedom X 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 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
incandescent lights 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 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.
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 ½ hp (the transfer
relays are rated at 2 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
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 X may take a long time (~ 0.1–0.2 seconds) 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 for power.
