Xantrex Technology 815-3024 Inverter Applications, Resistive Loads, Motor Loads, Problem Loads

Freedom SW 3K2K InvChg Owners Guide.book Page 66 Wednesday, October 9, 2013 1:34 PM

Troubleshooting

Inverter Applications

The Freedom SW 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

Resistive loads are the easiest and most efficient to drive. Voltage and current are in phase, which means they are in step with one another. Resistive loads 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 may be able to accommodate the load, the size of battery bank will limit inverter run time.

Motor Loads

Induction motors (AC motors without brushes) require up to six times their running current on startup. The most demanding are those that start under load (for example, compressors and pumps). Of the capacitor start motors (typical in drill presses and band saws, for example), the largest you can expect to run is 1 horsepower. Universal motors are generally easier to start. Check that the Locked Rotor Amps (LRA) rating of the motor load does not exceed the maximum surge current rating of the inverter. 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, the inverter may shut down from an AC overload fault.

Problem Loads

Very Small Loads If the power consumed by a device is less than the threshold of the search mode circuitry, and search mode is enabled, the inverter will not run. Most likely the solution will be to disable Search mode or lower the sense threshold.

Fluorescent Lights and Power Supplies Some devices cannot be detected when scanned by search mode circuitry. Small fluorescent lights are the most common example. Some computers and sophisticated electronics have power supplies that do not present a load until line voltage is available. When this occurs, each unit waits for the other to begin. To drive these loads, either a small companion load like a light bulb rated for more than the Search Watts setting must be used to bring the inverter out of search mode, or the inverter may be programmed to remain on by disabling Search mode. (See “Using Search Mode” on page 34.)

Clocks You may notice that your clocks are not accurate. Some of the clocks on your appliances may reset when the Freedom SW is in search mode.

Searching When the inverter is in search mode, it may fail to start some loads even though the rated wattage on the load is more than the Search Watts setting. Disable Search or apply an additional load (companion load) to make the inverter exit search mode.

66 Freedom SW Owner’s Guide