Control Resources’ custom electronic design and manufacturing group provided a telecom fan controller for this unique fan tray design. This custom fan controller included power regulation and I2C communications. Our experience with telecom fan controller design optimized this fan tray for maximum performance and reliability. CRI’s electronic design and manufacturing facilities have the capability to provide complete custom fan tray solutions from prototype to production.
Custom Fan Tray Controller Specifications
- Input Voltage: -36 to -72 VDC
- Dual input, diode OR’ed on both positive and negative feeds
- Fused on all lines (four fuses)
- Reverse polarity protection
- Output Power: 240 Watts, 9 Amps at 24 VDC
- Efficiency >90+%
- Fan soft-start with in-rush limiting
- Hot-swap capable
- Over-voltage and over-current protection
- Low voltage lock-out
- I2C communications specifications:
- PWM fan speed control
- Tachometer fan speed reporting
- Fan & temperature alarm reporting
- Custom fan tray design specifications:
- Reliability prediction per Telcordia TR/SR-332 at 40C
- MTBF per TR/SR-332 of 1,000+ khrs
- Field replaceable, hot-pluggable, and 1+1 redundancy
- Single fan tray failure will not be service limiting
- PCB size is constrained by fan placement requiring the design to fit “between” fans.