Thermistor motor protection relay compact evaluation device, 17.5 mm housing, screw connection, 1 changeover contact, US = AC/DC 24 V-240 V, auto-RESET, suitable for bimetal switches, supply = output voltage, 1 LED (TRIPPED) Thermistor motor protection relay SIRIUS 3RN2 for protecting motors from overheating by direct temperature measurement. The direct measurement of the motor winding temperature enables the protection of a motor even under unusual conditions such as heavy starting, braking operation, frequent switching or inadequate cooling and thus saves the need for precautionary oversizing of the motor. By using PTC sensors or bimetal switches, parameterization of the devices is not necessary. LEDs enable rapid error diagnosis. The devices are climate-proof, touch-safe and can be used worldwide thanks to the wide voltage range and international approvals. Available as mono- or bistable evaluation devices, with and without ATEX approval, with one or two sensor circuits and with auto, manual and/or remote RESET. The devices are available in screw or spring-loaded technology (push-in). There are versions with a width of 17.5 mm or 22.5 mm, for a TH35 top hat rail or for screw fastening with an adapter (accessory) and with hard gold-plated contacts. Uniform accessories for all device variants, such as removable terminals, push-in tabs and coding pins simplify selection and storage. The 3RN2 thermistor motor protection relays replace the proven 3RN1 series. SIRIUS relays - a program for all situations.
| Property | Value |
| Number of contacts as changeover contacts: | 1 |
| Number of measuring circuits: | 1 |
| Width: | 17.5 mm |
| External reset possible: | no |
| Error storage possible: | no |
| Height: | 100 mm |
| Depth: | 90 mm |
