APW Electronics has introduced a new range of monitored fan trays (MFTs) for use in its own IMserv server racks or in any standard 19in enclosure.
APW Electronics has introduced a new range of monitored fan trays (MFTs) for use in its own IMserv server racks or in any standard 19in enclosure. The MFT provide the best compromise between cooling effectiveness, noise generation and fan life by dynamically adjusting the fan speed as the temperature changes. The fan tray uses 38mm thick fans to maximise the air throughput, and careful design and material selection enables a wire mesh grill to be used without contravening the 44.45mm 1U height limit.

A mesh grill is preferred because there is much less restriction to the airflow than when apertures are punched from sheet material; the rounded profile of the wire mesh also contributes significantly to reducing noise levels.

The low profile 1U height enables units to be sited under hot spots as required without taking up more than the minimum possible rack height.

To control the fan speed, three different types of sensor are available: fixed or adjustable air sensors and a contact sensor.

A maximum of three sensors can be used on any one MFT, and each sensor can control from one to six fans.

A typical configuration may consist of a top mounted three-fan tray fitted with a fixed temperature sensor and a further three fans sited under two hot spots controlled by a remote sensor.

In the event of a sensor failure, the MFT defaults to full speed operation.

The fan speed is varied according to temperature, typically between 60% and 100% of full speed.

The default setting linearly increases the fan speed from 60% at 20C to 100% at 50C; both the temperature extremes and the spread are adjustable, allowing, for instance, the speed range to be compressed to 60% at 20C and 100% at 30C if a lower maximum temperature is required.

The MFT uses low voltage DC fans, powered from an integral 110/230V AC user-selectable power supply.

Volt-free changeover relay contacts are provided for activating or shutting down ancillary equipment, and audible, visible and TTL signal warnings of a fault condition are a further option.

The unit is available in two depths: 250mm deep, fitted with three fans and 350mm deep that can be fitted with up to six fans.