Control- and safety isolating transformer
ST 250/4/42 - 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 | Control- and safety isolating transformer |
Order number | ST 250/4/42 |
Power | 250 VA |
Input | 380 V / 400 V / 420 V |
Output | 42 V • 5.95 Aac |
Phases | 1 |
Frequency range | 50 Hz to 60 Hz |
Short-Circuit Losses | 18 W |
No-Load Losses | 11.5 W |
Short-Term Power / instantaneous output | 555 VA |
EN insulation class | B (130°C) |
UL Insulation class | class 105 |
Duty Cycle | 100 % |
Wire material | Copper |
Efficiency | 89.4 % |
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 | IP 00 |
Protection class (prepared) | I |
Overvoltage category | III |
Degree of contamination | 2 |
Electrical Connections
Terminal Pri | Screw terminal |
Terminal Sec | Screw terminal |
Terminal PE | Flat plug connection |
Size and Weight
Weight | 3.7 kg / 8.16 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) |