Control- and safety isolating transformer
STU 250/24
Characteristics
General data
The control transformers of the STU series are designed for universal voltage adjustment and safe galvanic isolation of the primary circuit from the secondary circuit. The unique BLOCK IMPEX vacuum impregnation process provides excellent protection against external influences while reducing noise levels. The robust metal base plate with elongated holes ensures easy and secure mounting.
Benefits
› Control and safety isolating transformer according to EN (IEC) 61558-2-2 and EN (IEC) 61558-2-6
› Very good inrush behavior due to reduced inrush currents
› High power density through a compact design concept
› Touch-protected connection terminals according to UVV BGV A3
| Product | Control- and safety isolating transformer |
| Order number | STU 250/24 |
| Series | STU |
| Power | 250 VA |
| Input | 230 V / 400 V / 460 V / 520 V ± 20 V |
| Output | 24 V • 10.4 Aac |
| Phases | 1 |
| Frequency range | 50 Hz to 60 Hz |
| Short-Circuit Losses | 23.5 W |
| No-Load Losses | 7.5 W |
| Short-Term Power / instantaneous output | 555 VA |
| Short circuit voltage uk | 8.6 % |
| EN Insulation class | B (130°C) |
| UL Insulation class | class 105 |
| Duty Cycle | 100 % |
| Wire material | Copper |
| Efficiency | 89 % |
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 | 120 mm / 4.72 in |
| Height | 123 mm / 4.84 in |
| Depth | 92 mm / 3.62 in |
| Weight | 4.3 kg / 9.48 lbs |
| Low Voltage Directive |
EN 61558-2-2 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) |
