Vector VEC1043 user manual Protective Features of the Inverter, HOW this Inverter Works

VEC1043_ManualEN_091505 1/17/06 5:49 PM Page 2

inverter, the red LED indicates inverter shutdown from an over-load or over- temperature fault and the yellow LED indicates an input fault. In addition to turning the unit ON and OFF, the ON/OFF Pushbutton can be used to force reset of the inverter circuits.

Figure 3 Top Panel

not read the RMS voltage of a modified sine wave correctly. They will read about 20 to 30 volts low when measuring the output of the inverter. For accurate measurement of the output voltage of this unit, use a true RMS reading voltmeter such as a Fluke 179, Fluke 79 III series, Beckman 4410, or Triplett 4200.

Modified Sine Wave and Sine Wave Comparison

POWER

OUTPUT FAULT

ON/OFF

PUSHBUTTON

INPUT FAULT

PROTECTIVE FEATURES OF THE INVERTER

The Power Inverter monitors the following potentially hazardous conditions:

HOW THIS INVERTER WORKS

The power inverter converts low voltage DC (direct current) from a battery or other power source to standard 115 volt AC (alternating current) household power.

Principle of Operation

The inverter converts power in two stages. The first stage is a DC to DC conversion process that raises the low voltage DC at the inverter input to 145 volts DC. The second stage is the actual inverter stage that converts the high voltage DC current into 115 volts, 60 Hz AC current.

The DC-to-DC converter stage uses modern high frequency power conversion techniques that have replaced the bulky transformers found in less technologically- advanced models. The inverter stage uses advanced power MOSFET transistors in a full bridge configuration. This ensures excellent overload capacity.

This condition is not harmful to the inverter, but could damage the power source. An alarm will sound when input voltage drops below 11 volts. The Power Inverter automatically shuts down when input voltage drops below 10 volts. When the condition is corrected, the inverter can be reset by turning OFF, then back ON.

The Power Inverter will automatically shutdown when the input voltage exceeds 15.5 volts DC.

The unit will automatically shut down when the continuous draw exceeds 750 watts. Reduce the load and manually reset using the inverter’s ON/OFF Pushbutton.

If the temperature inside the Power Inverter reaches 150°F, the unit will automatically shut down. Allow the unit to cool for at least 15 minutes before restarting after a heat-related shutdown. Unplug the unit while cooling.

If the low voltage alarm sounds when the battery is fully charged, follow the steps outlined in the “Troubleshooting” section of this User’s Manual. The alarm will sound

12VDC to

145VDC

CONVERSION

12VDC
	Internal
Input	Fuses

145VDC to

115VAC

CONVERSION

AC	115VAC, 60Hz
Outlet	to AC appliances

if there is an excessive voltage drop between the battery and the inverter.

Notes: It is normal for the alarm to sound while the unit is being connected to, or disconnected from, the power source. This is not indicative of a problem.

Reverse polarity or short circuit condition may cause external or internal fuses to open and may cause irreversible damage to the Power Inverter. Take extra care to ensure a proper polarity hook-up.

The Power Inverter Output Waveform

The AC output waveform of the Power Inverter is known as “modified sine wave.” It is a waveform that has characteristics similar to the sine wave shape of utility power. This type of waveform is suitable for most AC loads, including linear and switching power supplies used in electronic equipment, transformers, and motors.

The modified sine wave produced by the Power Inverter has an RMS (root mean square) voltage of 115 volts, which is the same as standard household power. Most AC voltmeters (both digital and analog) are sensitive to the average value of the waveform rather than the RMS value. They are calibrated for RMS voltage under the assumption that the waveform measured will be a pure sine wave. These meters will

INSTALLATION AND OPERATING INSTRUCTIONS

Power Source Requirements

The power source must provide a nominal voltage of 12.5 volts DC and must be able to supply the necessary current to operate the load. The power source may be a battery or a well-regulated DC power supply. To obtain a rough estimate of the current (in amperes) the power source must deliver, simply divide the power consumption of the load (in watts AC) by 10.

Example: If a load is rated at 750 watts AC, the power source must be able to deliver: 750 divided by 10 = 75 amperes.

2 3