Description
Honeywell 621-6575
Technical Specifications
- Supply voltage: 24 V DC
- Operating current: 0.25 A
- Rotational speed: 3000 RPM
- Airflow rating: 70 CFM
- Fault alarm: Passive dry contact output, actuates on fan stop
- Protection rating: IP20
- Operating temperature: 0 °C to +60 °C
- Noise level: 40 dB(A)
Functional Features Dual ball bearing fan, long continuous operating service life. Hall speed monitoring, fan stop or speed drop triggers alarm contact actuation. Dust filter on air intake, blocks dust from entering the cabinet interior. Hot swap compatible, unit replacement does not interrupt system operation. Metal fan frame reliably grounded, prevents static charge accumulation.
Application Scenarios Cabinet internal forced cooling for 621 PLC systems Ventilation unit for high-temperature environment control cabinets Spare part replacement for stuck fans with degraded speed and noise Ventilation component for new control cabinet assembly
Performance Parameters
- Bearing rated service life: 50000 hours at 40 °C ambient
- Alarm trigger speed threshold: <2000 RPM
- Startup voltage: 18 V DC
- Static pressure: 0.1 inch H2O
- Surge tolerance: ±2 kV contact electrostatic discharge
Material Composition Modified PBT plastic fan blades Brushless DC motor with dual ball bearings Galvanized steel fan frame Nylon dust filter mesh Sealed reed alarm contact Galvanized steel mounting bracket
Structural Features Square standard fan dimensions, with fixed mounting bracket. Dust filter clip-fitted to the air intake side. Wiring leads include 24 V power wires and alarm contact wires. Air guide shroud directs vertical airflow across the rack. Mounting hole pattern matches standard control cabinet fan cutout dimensions.
Working Principle 24 V DC supply drives the brushless motor, spinning blades to generate directional airflow. External cool air passes through the filter to remove dust particles, enters the cabinet, picks up heat from boards and power supplies, and exhausts through the cabinet top vent. The Hall sensor continuously measures fan rotational speed; when speed drops below threshold, the on-board reed relay contact actuates, outputting a fan fault signal to the control system, prompting maintenance staff to schedule service.
Installation Requirements Mount the fan on the cabinet air intake side, airflow direction flows from outside to inside the cabinet. Keep intake and exhaust paths unobstructed, do not block fan rotation area with cabling. Wire alarm contact signals into the cabinet temperature monitoring loop. Match supply power polarity correctly; reversed connection stops fan operation and damages the motor. Remove and clean the dust filter quarterly.
Usage Notes Clogged dust filter reduces cooling airflow, clean filter every 3 months. Stuck fan bearings trigger fault alarms; replace promptly with matched fan units. Never insert hands into moving fan blades, risk of mechanical injury. Inspect wiring insulation regularly, damaged insulation causes short circuit and fan stop.
