TE Technology TC-48-20 - Manual (Page 12)

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If you wish to limit the output voltage of the power supply to less than its full scale voltage you can adjust a
controller parameter called the ANALOG OUTPUT MULTIPLIER. For example, assume you have chosen to use a
Kepco RKW 24‐65K model power supply. This is a 1500 watt power supply with a full‐scale output of 24 V and 65
A. If you wish to limit the output voltage to approximately 20 V, you can set the analog multiplier to 0.83 (20V /
24V). This scales the analog output voltage to 4.15 V and thus limits the output voltage of the power supply
accordingly. The ANALOG OUTPUT MULTIPLIER is scalable only by communicating with the controller via the
software through the RS‐232 interface. An RS‐232 cable, part number MP‐3023 or equivalent, is required to
connect the controller to a computer. The factory default value for the ANALOG OUTPUT MULTIPLIER is 1.
Using alarm outputs for multi‐speed fan control and other load control
The alarm outputs can be configured to operate a fan at two different speeds, which is useful for keeping fan noise
to a minimum. For example, by using a second sensor to measure the ambient air temperature, ALARM 2 can be
used to run the fan at high speed only when the ambient air temperature is high and increased cooling capacity is
needed. Alternately, the second sensor can measure the heat sink temperature. If the heat sink temperature
begins to rise because the ambient temperature is increasing or because the heat source is active, ALARM 2 is
triggered to run the hot‐side fan at full speed. An external resistor, placed in series with the fan, is required.
The alarms can also be configured to activate other loads such as pumps and resistive heaters. A fixed value
resistor can be used in place of the second sensor, causing the controller to interpret the fixed resistance as a fixed
temperature. Changing the alarm temperature above or below this fixed temperature will then cause the alarm,
and consequently the load, to be activated or deactivated. The second sensor temperature display can also be
turned off when the temperature data is not relevant.