The Elgar 1503 AC Power Source provides three phase AC power output at adjustable amplitude and precise frequencies for use in test purposes, motor operation, and frequency conversion. The amplitude is adjustable from 0 to 130 VAC. The frequency range of the AC power sources is 45 Hz to 5 KHz. The output frequency is controlled by an Elgar three-phase plug-in oscillator, which is available in either variable frequency or fixed frequencies with accuracies up to .0001%.
The Elgar 1503 AC Power Source functionally consists of two DC power supplies, three power amplifiers with associated control circuitry and a three-phase output power transformer. The DC supplies are obtained from a full wave bridge rectifier on the secondary of the input power transformer. These supplies are a nominal plus and minus 45V DC. They are used as the operating and bias voltages in the three amplifiers. The three power amplifiers are mounted on heatsink assemblies whose inputs are controlled by three plug-in amplifier circuit boards. The Elgar plug-in oscillator signals are AC coupled to the inputs of the circuit boards and determine the A, B, and C phase outputs. The amplitude of the three power amplifier signals is varied simultaneously by the front panel amplitude control potentiometer. The amplified A, B, and C phase signals are applied to the output transformer, whose secondaries are connected to the front panel binding posts and the rear panel output power terminal block.
Specifications
| Output Power Per Phase | 0-500 |
| Power Factor | Unity to ± .7 |
| Output Voltage (adjustable) | 0-130 VAC line to neutral and
0-130 VAC line to line simultaneously |
| Output Configuration | 4 wire wye, isolated from ground. Any one phase or neutral can be grounded. |
| Output Frequency Range | 45 Hz - 5 KHz at rated power |
| Distortion | Less than .9% (45 Hz - 5 KHz)
Less than .5% (400 Hz - 1 KHz) |
Load Regulation
(Regulation may be adjusted thru
zero for specific loads and frequencies) | Line to Neutral: Less than 1%
Line to Line Balanced Load:
Less than 1% (45 Hz to 800 Hz)
Less than 3% (800 Hz to 5 KHz) |
| Line Regulation | + .25% for 10% input line change |
| Hum and Noise | -70 db below full output |
| Input Power | 115 or 230V line to neutral or line to line; 3-phase 47-63 Hz, 3 KVA maximum input power |