Airstream TC4-2N6F User Manual page 13

Outside probe
If the outside probe is defective, the display shows the letter "P" when the
parameter selection knob is set to OUTSIDE SETTINGS and the outside set
point temporarily becomes deactivated (
page 23). The Defective Probe Pilot Light does not turn on when this happens.
Motor Curves
T
he relationship between the voltage supplied to a motor and its operating
speed is described by a motor curve. This curve varies with the make and
capacity of the motor. The various motors available in the industry have
been divided into ten categories and the controller has been programmed
with a different motor curve for each of these categories. Select the
appropriate curve to ensure that the controller supplies the correct voltage
to the variable speed fan motors. When the controller is shipped from the
factory, curve number 4 has been selected.
To Select a Motor Curve for Stage 1
In the list of motors enclosed with this user's manual, locate the
make and capacity of your stage 1 variable speed motors and note
the corresponding curve number (1 to 10).
Set the parameter selection knob to BAND WIDTH - STAGE 1. The
stage 1 band width appears flashing on the display.
Press the push-button. The currently selected curve number
appears flashing on the display.
Using the adjustment knob, adjust the curve number to the desired
value.
Return to the stage 1 band width display either by pressing the push-
button once again or by waiting 10 seconds without changing the
position of the adjustment knob.
To Select a Motor Curve for Stage 2
Repeat the steps described above, this time setting the parameter
selection knob to DIFFERENTIAL - STAGE 2.
refer to "Outside Set Point",
TC4-2N6F.rev.07
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