According to GB 3836.1 and GB 3836.2 standards, explosion-proof electric heaters must be used in conjunction with temperature interlock control and protection devices such as thermocouples; otherwise, risks such as overheating and dry burning will increase significantly. The BDR-45 explosion-proof electric heater integrates over-temperature protection, low liquid level/dry burn protection, pressure interlock, and flow monitoring, and can output alarm signals such as running, high temperature, and fault to DCS/PLC systems. If interlock testing is neglected during maintenance, protection may fail.
Operation and maintenance personnel should simulate over-temperature and low liquid level signals monthly to confirm that the heater can automatically cut off the power supply; check the pressure interlock and flow monitoring action values quarterly to avoid misjudgment caused by sensor drift. Alarm signals should be uploaded to DCS/PLC simultaneously, and response times should be recorded.
Flameproof surfaces must not be bumped or corroded, and fastening bolts must be complete and tightened to the specified torque. Sealing rings of cable entry devices should be replaced promptly after aging to prevent explosive gas from entering the wiring cavity.
Pay attention to the heater surface temperature, current balance, and insulation resistance, and shut down for troubleshooting promptly if abnormalities are found. Before restarting after long-term shutdown, first confirm that the interlock protection is normal, then put it into operation. Maintenance records should be kept on site for traceability.
