Isolating transformer
ST 20/69/4 - Discontinued types – not for new designs
Characteristics
Benefits
› Very good switch-on behaviour thanks to reduced starting currents
› High power density due to a compact construction design
› Primary side ±5 % tappings for voltage adjustment
› Very good corrosion protection and low noise thanks to BLOCK IMPEX vacuum impregnation
› Contact protected screw connection terminals complying with UVV BGV A3
› Simple mounting thanks to robust metal footplate with oval slots
| Product | Isolating transformer |
| Order number | ST 20/69/4 |
| Series | ST |
| Power | 20 VA |
| Input | 655 V / 690 V / 725 V |
| Output | 400 V • 0.05 Aac |
| Phases | 1 |
| Frequency range | 50 Hz to 60 Hz |
| Short-Circuit Losses | 2.72 W |
| No-Load Losses | 1.85 W |
| EN Insulation class | B (130°C) |
| Duty Cycle | 100 % |
| Wire material | Copper |
| Efficiency | 81.4 % |
General
| Short circuit proof | not short-circuit proof |
| Switching group | Ii0 |
| 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 | IP00 |
| Protection class (prepared) | I |
| Overvoltage category | III |
| Degree of contamination | 1 |
Electrical Connections
| Input terminal | Screw terminal |
| Output terminal | Screw terminal |
| Terminal PE | Flat plug connection |
Size and Weight
| Weight | 0.663 kg / 1.462 lbs |
| Low Voltage Directive | EN 61558-2-4 |
