LME23.331C2 Siemens Burner Control

Overview

The Siemens LME23.331C2 is a high-performance, microprocessor-based burner control unit designed for the startup and supervision of 1- or 2-stage gas or gas/oil burners. Engineered for intermittent operation, this controller is suitable for burners of small to medium capacity, with or without a fan. It serves as a reliable replacement for legacy LGB and LMG series controls, utilizing digital signal handling to ensure an accurate control sequence. The LME23.331C2 provides essential safety functions, including undervoltage detection and air pressure supervision, making it a critical component for commercial and industrial heating systems.

Features

• Microprocessor-controlled digital signal handling for high precision and repeatable timing
• Multicolor LED for real-time indication of operational status and fault messages
• Undervoltage detection mechanism that triggers a safety shutdown if mains voltage drops below a safe threshold
• Air pressure supervision with a functional check of the air pressure switch during startup and operation
• Electrical remote reset facility for easy system recovery after a lockout
• Limitation of the number of repetitions to prevent hazardous startup attempts
• Controlled intermittent operation with a mandatory shutdown after a maximum of 24 hours of continuous use

Specifications

• Model: LME23.331C2
• Supply Voltage: AC 230 V (+10%/-15%)
• Frequency: 50 to 60 Hz (+/- 6%)
• Power Consumption: 12 VA
• Waiting Time (tw): 2.5 seconds
• Prepurge Time (t1): 30 seconds
• Safety Time (TSA): 3 seconds
• Preignition Time (t3): 2 seconds
• Actuator Running Time: 12 seconds
• Protection Rating: IP40 (when properly mounted)
• Weight: Approximately 160g

Applications

• Supervision of 1- or 2-stage gas or gas/oil burners in intermittent operation
• Forced draft burners utilizing an ionization probe or QRA flame detector with an AGQ3 ancillary unit
• Blue-burning flames monitored with QRC blue-flame detectors
• Use in automated forced draft burners for gaseous fuels in accordance with EN 676
• Integration into commercial and industrial heating plants, boilers, and thermal process equipment