MTL5561 Eaton Fire Detector Interface MTL

Eaton MTL5561 Fire and Smoke Detector Interface

Product Introduction

The MTL5561 belongs to the MTL5500 Series from Eaton. It provides two fully floating, loop-powered channels. You can connect conventional fire and smoke detectors located in hazardous areas. Additionally, the unit triggers a corresponding change in the safe-area current. This change alerts your control system.

Reverse input polarity protection comes standard. Therefore, wiring mistakes will not damage the module. Each channel operates independently. This design saves panel space while maintaining safety.

Technical Specifications

Input and Current Ranges

Input voltage spans 6 to 30V dc. Current range runs from 1 to 40mA nominal. Quiescent safe-area current at 20°C stays under 400µA per channel. This occurs when hazardous-area terminals are open circuit.

Output Voltage Characteristics

For Vin ≤ 25V, Vout = Vin – (0.38 x current in mA) – 2V. For Vin > 25V, Vout = 22.5V – (0.35 x current in mA). Maximum output voltage reaches 28V from 300Ω.

Transfer Accuracy and Drift

Transfer accuracy at 20°C is better than 400µA. Temperature drift stays under 4µA/°C from 0°C to 60°C. Between -20°C and 0°C, drift remains below 15µA/°C. These values ensure reliable trip detection.

Response Time

Response time to a step input settles within 5% of final value in just 1.5ms. Consequently, your system receives alarm signals almost instantly. This speed helps meet safety integrity requirements.

Polarity Protection

Integral input polarity protection guards each channel. You can reverse the input wiring accidentally. The MTL5561 will not suffer damage. Simply correct the wiring, and normal operation resumes.

Power and Safety Parameters

Power Dissipation

Maximum power dissipation reaches 0.7W at 24V with 40mA signal per channel. At 30V with the same 40mA signal, dissipation goes up to 0.9W per channel. Total dissipation stays low, reducing heat in enclosures.

Safety Description Per Channel

Safety parameters are Uo=28V, Io=93mA, Po=0.65W. Um equals 253V rms or dc. These values comply with hazardous area requirements. Each channel meets Zone 0, IIC, T4–6 certification standards.

Mechanical and Environmental Parameters

Dimensions and Mounting

Product length is 109.8 mm. Height measures 118.8 mm. Width stays at 15.8 mm. Weight equals 150 g. Mounting method uses a T-section 35mm DIN rail.

Temperature and Humidity

Minimum ambient operating temperature is -20°C. Maximum ambient operating temperature is 60°C. Storage temperature ranges from -40°C to 80°C. Humidity tolerance spans 5-95% relative humidity, non-condensing.

LED Indication

A green LED indicates power is present on each channel. However, the MTL5561 is loop-powered. The LED confirms the loop is active and properly connected.

Installation Guidelines

First, mount the MTL5561 on a 35mm DIN rail. Ensure the rail is grounded properly. Next, connect the hazardous area detectors to the input terminals. Pay attention to polarity, though reverse protection exists.

Then, wire the safe-area outputs to your controller or PLC. Each channel operates independently. Use crimp ferrules for conductors up to 2.5mm² stranded or single-core. Keep field wiring separated from high-voltage cables.

Finally, test each channel by triggering a detector. Verify the safe-area current changes as expected. Measure quiescent current with open-circuit hazardous terminals. It should stay below 400µA per channel at 24V.

Packaging List

• 1 x Eaton MTL5561 fire and smoke detector interface

• 1 x terminal identification label

• 2 x DIN rail mounting clips

• 4 x blanking plugs

Note: Certificates and warranty documents are not included. They ship separately.

Shipping carrier: Fedex, UPS, DHL

Frequently Asked Questions

1. Can the MTL5561 work with addressable fire detectors?
No, this unit works only with conventional detectors. Addressable detectors require different interface modules.

2. What happens if input voltage drops below 6V?
The unit may not function correctly. Transfer accuracy and response time could degrade. Always keep Vin between 6 and 30V dc.

3. Does the Eaton MTL5561 support both channels simultaneously?
Yes, both channels operate fully independently. You can drive two separate detectors or zones from one module.

4. How do I know if a detector has triggered?
The safe-area current changes noticeably. Your control system monitors this change. No separate alarm output exists.

5. Is the 1.5ms response time guaranteed across all temperatures?
It is typical at 20°C. Extreme temperatures may slightly increase response time. However, the unit still performs reliably within specifications.