Safety isolating transformer
ST 20/11/24
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 | Safety isolating transformer |
| Order number | ST 20/11/24 |
| Series | ST |
| Power | 20 VA |
| Input | 109 V / 115 V / 121 V |
| Output | 24 V • 0.83 Aac |
| Phases | 1 |
| Frequency range | 50 Hz to 60 Hz |
| EN insulation class | B (130°C) |
| UL Insulation class | class 105 |
| Duty Cycle | 100 % |
| Wire material | Copper |
| Efficiency | 81 % |
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 | IP 00 |
| Protection class (prepared) | I |
| Overvoltage category | III |
| Degree of contamination | 2 |
Electrical Connections
| Input terminal | Screw terminal |
| Output terminal | Screw terminal |
| Terminal PE | Flat plug connection |
Size and Weight
| Width | 66 mm / 2.6 in |
| Height | 81 mm / 3.19 in |
| Depth | 56 mm / 2.2 in |
| Weight | 0.65 kg / 1.43 lbs |
| Low Voltage Directive | EN 61558-2-6 |
| Approval cURus - Recognized | UL 5085-1/-2; CSA 22.2 |
| VDE Approval |
VDE 0570-2-x (DIN EN 61558-2-x) |
