MTL5061 Fire Smoke Detector Interface - MTL Instruments

MTL5061 Fire & Smoke Detector Interface

The MTL5061 from MTL Instruments is a loop-powered dual-channel interface designed for fire and smoke detectors in hazardous areas. This specialized unit provides reliable signal transmission from detectors to safe-area monitoring systems. 

Key Technical Specifications

• Brand: MTL Instruments
• Model: MTL5061
• Product Type: Fire & Smoke Detector Interface
• Channels: Two independent channels
• Power Type: Loop-powered operation
• Current Range: 1 to 40mA nominal
• Response Time: 30ms maximum

Hazardous Area Certification

• Detector Location: Zone 0, IIC, T4-T6 hazardous area
• Division Rating: Division 1, Group A hazardous location
• The MTL5061 maintains intrinsic safety for fire detection systems
• It enables safe operation of detectors in explosive atmospheres

Electrical Performance

• Current Range: 1 to 40mA nominal operating range
• Transfer Accuracy: Better than 400µA at 20°C
• Temperature Drift: <10µA/°C (-20 to 60°C)
• Response Time: Settles within 30ms to 500µA of final value
• Quiescent Current: <400µA per channel at 24V DC

Output Characteristics

• Maximum Output Voltage: 28V from 300Ω
• Minimum Output Voltage: Lower of Vin – (0.38 x mA) – 2V or 21V – (0.35 x mA)
• Automatic voltage calculation based on current draw
• Stable output performance across operating range

Power Requirements

• Loop Supply Voltage: 6 to 35V DC operating range
• Power Dissipation: 0.7W at 24V with 40mA signal per channel
• Maximum Dissipation: 1.2W at 35V with 40mA signal per channel
• Loop-powered design simplifies installation

Terminal Configuration

• Channel 1 Output: Terminal 1 (Output –ve), Terminal 2 (Output +ve)
• Channel 1 Input: Terminal 11 (Input –ve), Terminal 12 (Input +ve)
• Channel 1 Earth: Terminal 3 for leakage detection
• Channel 2 Output: Terminal 4 (Output –ve), Terminal 5 (Output +ve)
• Channel 2 Input: Terminal 8 (Input –ve), Terminal 9 (Input +ve)
• Channel 2 Earth: Terminal 6 for leakage detection

Safety Parameters

• Safety Voltage: 28V maximum
• Internal Resistance: 300Ω
• Safety Current: 93mA maximum
• Isolation Voltage: Um = 250V rms or DC
• Comprehensive protection for fire safety applications

Frequently Asked Questions

• What detectors is the MTL5061 designed for?
  It interfaces with conventional fire and smoke detectors in hazardous areas.
• How does earth fault detection work?
  Optional 'non-fail' detection via MTL4220 unit allows continued operation during faults.
• What is the response time for detector signals?
  It settles within 30ms to within 500µA of the final value.
• Is reverse polarity protection included?
  Yes, the input circuit has integrated reverse polarity protection.