Autotransformer, three-phase
AT3 250-20/21-4
Characteristics
General data
The autotransformers of the AT3 series are used for voltage adjustment without the need for galvanic isolation. The multifunctional and widely used base brackets provide variable mounting options and facilitate top-side installation. The transformers are equipped with crane eyelets to simplify transportation.
Benefits
› Autotransformer according to EN (IEC) 61558-2-13
› Reverse operation possible
› Very high efficiency
› Patented mounting technology to reduce heat losses
› Excellent corrosion protection and low noise emission thanks to BLOCK IMPEX vacuum impregnation
› Fixed, touch-protected screw terminal connections according to UVV BGV A3
| Product | Autotransformer, three-phase |
| Order number | AT3 250-20/21-4 |
| Series | AT3 |
| Power | 250,000 VA |
| Input | 3 x 200 V / 208 V |
| Output | 3 x 400 V • 361 Aac |
| Phases | 3 |
| Frequency range | 50 Hz to 60 Hz |
| Short-Circuit Losses | 1808 W |
| No-Load Losses | 682 W |
| EN Insulation class | F (155°C) |
| UL Insulation class | class 155 |
| Duty Cycle | 100 % |
| Wire material | Copper |
| Efficiency | 99 % |
General
| Short circuit proof | not short-circuit proof |
| Switching group | Yna0 |
| Cooling type | AN |
Environment
| Ambient temperature | -20 °C to 40 °C / -4 °F to 104 °F |
| Max. installation height | 2,000 m / 6,562 ft |
Protection and Safety
| Protection type | IP 00 |
| Protection class (prepared) | I |
Electrical Connections
| Input terminal | Flat copper connection |
| Output terminal | Flat copper connection |
| Terminal PE | Bolt connection |
Size and Weight
| Width | 750 mm / 29.53 in |
| Height | 720 mm / 28.35 in |
| Depth | 600 mm / 23.62 in |
| Weight | 529 kg / 1166.244 lbs |
| Low Voltage Directive | EN 61558-2-13 |
