PTC Thermistor & Single Phasing Preventer Relay - 400 V AC, 1 NO + 1 NO is a combined PTC thermistor and single phasing preventer relay designed for 3-phase motor protection. It monitors thermistor over-temperature input with phase sequence, phase loss, and phase asymmetry faults in 400 V AC 3-phase, 3-wire systems.
🔧 Technical Highlights:
- Product type: PTC thermistor and single phasing preventer relay
- Supply voltage: 400 V AC, 3-phase 3-wire
- Output: 1 NO for single phasing protection + 1 NO for PTC thermistor protection
- Monitored functions: phase sequence, phase loss, phase asymmetry, and PTC thermistor over-temperature
- Trip level: 2.7 kΩ +/- 5%
- Reset level: 1.71 kΩ +/- 5%
- Contact rating: 5 A NO resistive at 240 V AC / 28 V DC
- Mounting: DIN rail, 22.5 mm housing
✅ Benefits:
- Combines temperature and phase-fault protection in one DIN rail relay.
- Helps protect 3-phase motors from overheating and supply faults.
- Provides separate normally open outputs for protection circuit wiring.
- Uses LED indication to support faster panel fault checks.
🚀 Applications:
- 3-phase motor protection panels
- Pump, fan, and compressor control circuits
- Industrial HVAC equipment
- Machine control panels requiring temperature and phase protection
MLD4BS provides combined PTC thermistor and phase-fault protection for dependable 3-phase motor control.
FAQs
- Q: What is the MLD4BS used for?
A: It protects 400 V AC 3-phase, 3-wire motor circuits by monitoring PTC thermistor temperature input and phase supply faults. - Q: What is the main selection detail for MLD4BS?
A: The key selection detail is a 400 V AC PTC thermistor and single phasing preventer relay with 1 NO + 1 NO outputs.