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Safe control transformers in hazardous areas
R. STAHL's control transformers provide explosion protection when control voltages are being supplied. They are suitable for control circuits, for functional and protective extra-low voltages and for electrical separation. Among their benefits are the fact that they are responsible for only a slight voltage drop when switching inductive loads, and that they limit the short-circuit current in the control circuit.

In accordance with EN 60204-1, with few exceptions, a transformer is necessary in control circuits. R. STAHL's control transformers boast a number of benefits – for example, they limit the short-circuit current in the control circuit, and are responsible for only a slight voltage drop when switching inductive loads. They are suitable for Ex Zones 1 and 2, and are generally used for control circuits, for electrical separation and for supplying protective (PELV) and safety (SELV) extra-low voltage. They must be protected on the primary side by a motor protection circuit breaker from trip class 10 or 10 A, and on the secondary side by a safety fuse or miniature circuit breaker. It goes without saying that these components are also available from R. STAHL.

  • Typical applications: Control circuits, protective extra-low voltage (PELV), safety extra-low voltage (SELV) and electrical separation
  • Line voltage can be adjusted at tapping points (primary side +/- 5%)
  • Short-circuit current limiting in the control circuit, small voltage drop when switching inductive loads

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Transformer Series STA

  • Low voltage drop in switching inductive loads
  • Flexible voltage adjustment by primary tapping (±5%)
  • Limitation of short-circuit current in control circuit
  • Typical applications: Control voltage circuits, functional extra-low voltage PELV, safety extra-low voltage SELV, protective separation (of circuits)

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