LMO44.255C2 Siemens Burner Control

Overview

The Siemens LMO44.255C2 is a microcontroller-based oil burner control designed for the startup, supervision, and control of forced draft oil burners in intermittent operation. It is specifically engineered for use with stationary direct-fired air heaters and can manage 1- or 2-stage burners with an oil throughput typically exceeding 30 kg/h. This advanced controller uses digital signal handling to provide an accurate and reproducible control sequence, making it a reliable choice for OEMs to integrate into their combustion products. It serves as a modern replacement for the legacy LOA series, sharing identical housing dimensions and electrical connections for easy upgrades.

Features

• Microprocessor-controlled for precise and repeatable timing sequences
• Designed for intermittent operation with a controlled restart after 24 hours of continuous use
• Integrated undervoltage detection to prevent unsafe operation during power fluctuations
• Multicolor LED indication for clear communication of operational status and fault diagnostics
• Bridging contact and time monitoring for oil preheaters
• Electrical remote reset facility for convenient system management
• Limitation of the number of repetitions to enhance safety during ignition failures
• Compatible with QRB photoresistive detectors for yellow-burning flames and QRC blue-flame detectors

Specifications

• Model: LMO44.255C2
• Mains Voltage: AC 230 V (+10% / -15%)
• Mains Frequency: 50 to 60 Hz (+/- 6%)
• Power Consumption: Approximately 12 VA
• Primary External Fuse: 6.3 A (slow)
• Ignition Safety Time (TSA max): 5 seconds
• Post-ignition Time (t3n): 5 seconds
• Degree of Protection: IP40 (ensured through mounting)
• Operating Temperature: -20 C to +60 C
• Weight: Approximately 200 g
• Mounting Orientation: Optional

Applications

• Supervision of 1- or 2-stage forced draft oil burners
• Specifically suited for stationary direct-fired air heaters
• Ideal for atomization oil burners of monoblock design in accordance with EN 230
• Used in oil burners with fans meeting EN 267 standards
• Suitable for industrial and commercial combustion plants requiring high-precision oil burner management