GIC & HIQUEL Thermistor Over-Temperature Relays

GIC and HIQUEL Thermistor Over-Temperature Relays are designed to protect motors, transformers, and industrial equipment against overheating. These intelligent relays continuously monitor resistance changes in PTC (Positive Temperature Coefficient) sensors embedded in the windings or housing of machines. When temperature exceeds the preset threshold, the relay trips to disconnect or signal a fault, preventing costly thermal damage.

🔧 Technical Highlights:

• Function: Monitors thermistor (PTC) sensor resistance to detect over-temperature conditions.
• Sensor Input: Supports 1–6 PTC sensors connected in series (per DIN 44081/44082).
• Response: Trips when resistance exceeds approximately 3.3 kΩ; resets when value drops below 1.8 kΩ.
• Reset Mode: Selectable manual or automatic reset via front selector or remote input.
• Supply Voltage: Universal 24–240 V AC/DC (model dependent).
• Outputs: SPCO or DPCO relay contacts for alarm or trip control.
• Indication: LED indicators for power, sensor fault, and relay output state.
• Mounting: DIN rail 35 mm or panel mount, compact modular enclosure.
• Compliance: CE and RoHS; conforms to IEC/EN 60255 for thermal protection relays.

✅ Benefits:

• Provides direct thermal protection for motors and electrical machines.
• Fast detection and trip response prevent insulation damage and downtime.
• Works with standard PTC thermistors for universal compatibility.
• Selectable reset mode adapts to automation or safety requirements.
• Reliable, maintenance-free design from GIC and HIQUEL for continuous use.

🚀 Applications:

• Motor winding over-temperature protection.
• Transformer and generator thermal monitoring.
• Industrial heating elements and resistive load protection.
• Fans, pumps, and compressors in automation panels.
• Process equipment with embedded PTC thermal sensors.

GIC and HIQUEL thermistor over-temperature relays deliver precise and reliable PTC-based protection, ensuring equipment safety, reducing maintenance, and extending service life in industrial and automation systems.

FAQs

• Q: How does a thermistor relay protect a motor?
  A: It measures the resistance of PTC thermistors installed in the motor windings. When the winding temperature rises above a safe limit, the thermistor resistance increases and triggers the relay to disconnect the motor before damage occurs.
• Q: What is the difference between manual and automatic reset modes?
  A: In manual mode, the relay must be reset via a push button or control input after a trip; in automatic mode, it resets automatically once the temperature drops to a safe level.