Retrotec Speed Control Adapter (for TEC fans) - Manual (Page 10)

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©Retrotec Inc. 2014
4. Adapter Technical Details
4.1 Fan Compatibility
The Speed Control Adapter (for TEC fans) (Retrotec part number FN275) is designed to convert the fan
speed control output from Retrotec gauges to a Pulse Width Modulation (PWM) scheme required by the
cruise input on TEC fan speed control unit.
The Adapter thus works with any fans that use the TEC fan speed control unit, or a compatible PWM
speed control scheme.
4.2 Gauge Compatibility
The Speed Control Adapter is designed to work with the fan speed control output from Retrotec gauges,
including the DM32 and the DM-2. Given that DM-2 are reaching end of lifecycle, it would be prudent
for Speed Control Adapter users to use the DM32 to control their TEC fans.
4.3 LED Power Status Indicator
The LED on the front indicates the status of power internal to the Adapter. The Adapter uses an AA
battery to supplement the power provided by the Speed Control Output. A green light when plugged in
means that the Adapter battery has adequate charge.
When the battery voltage falls to +5.4V, the red light will come on as a ‘low battery’ indication, meaning
the internal battery needs to be changed (9V battery).
Battery life when used with the DM32 gauge is expected to be unlimited, since power from the battery
is only required when the fan is running at 90-100% speed.
When used with a DM-2 gauge, the battery will need to be changed at regular intervals, since the DM-2
speed control output needs more boosting.