The STW type current relay for current detection includes the coordinated STWA 1 current transformer. One current transformer is required for each monitored line. The STWA1 consists of a climate-resistant cast coil with a ferrite core. The connecting cables are permanently connected to the transformer and are 1 m long. The maximum current to be monitored is 100 A. 300 A is permissible for a maximum of 10 s.
The STWA1 current transformer can be used to directly control an LED for currents above approx. 2 A. This allows the user to visually display the current flow in a line in a simple way. The LED should be protected by a diode connected in anti-parallel or in series. Depending on the LED used and the level of the current to be monitored, a series resistor is required.
| Property | Value |
| Secondary connection: | Cable |
| Design: | Through-hole current transformer |
| Primary rated current: | 100 A |
| Snap-on fastening: | no |
| Number of primary inputs: | 1 |
| With copper bar: | no |
| Calibrated: | no |
| Opening diameter: | 11 mm |