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TC5-8SDA rev.03
TC5-8SDA
OUTSIDE TEMPERATURE COMPENSATION
The TC5-8SDA has the capability of automatically adjusting the
running time of the minimum ventilation fans as a function of outside
temperature. As the weather gets colder, the on time is decreased
gradually to compensate for the change. This can help reduce costs
by reducing the ventilation when it is not required. A curve is used
to calculate the required compensation as a percentage of current
on time (see following page). Only the running time is adjusted; the
total cycle time remains unchanged. Note that internal switch # 6
must be set to ON for this feature to work.
In the first example given on the following page, compensation is not
needed when the outside temperature is greater than 50
o
F. The fans
operate according to the full running time defined by the parameter
settings. In the second example, the running time is decreased to
66.5% of full running time to compensate for the colder outdoor
temperature. Cycle time remains unchanged.
TIME ON
CYCLE TIME
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ON
OFF
Outdoor Temperature > 50
o
F
Compensation = 100%
TIME ON
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ON
OFF
Outdoor Temperature = 25
o
F
Compensation = 66.5%
CYCLE TIME
Examples of Ventilation Compensations
