Vykon VT7607B5x28(X), Руководство пользователя

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Humidity setpoint reset by outside air temperature
If an outdoor air sensor is connected at the thermostat
or a value is received from the network, it can be used
to reset the humidity setpoint during the cold season to
minimize condensation on windows and building
structures.
When the outdoor temperature falls below the selected
high temperature, parameter
RH HT
(32
°
F in the
example Figure 8), the humidity setpoint will start to
decrease. The lowest humidity setpoint will be reached
at selected low temperature, parameter
RH LT
(-20
°
F).
The setpoint decrease from original setpoint to the
lowest setpoint determined by the parameter
RE Sp
. In
the example, Figure 8,
RE Sp
was set to 20%, therefore
the humidity setpoint dropped from 45% to 20%.
If you don’t want to use this feature, set the
RE Sp
parameter to 90% RH.
High limit humidity sensor
The VT76x7 series includes a high limit sequence. This
allows the use of a remote 0 to 10 Vdc humidity sensor to
limit the humidity in the supply air. If no sensor is detected at
the HL connector, this sequence is disabled at the
thermostat.
Note: this high limit function is not a safety device. For
critical situations, provide installation with normal protections
required to ensure a safe operation.
20%
25%
30%
35%
40%
-40°F -20°F 0°F 20°F 40°F
45%
%
RH S
etp
oi
nt
Outside Air Temp.
RH HT = 32°F
RH LT = -20°F
RH Set = 45%
RE Sp = 20%
Fig.11 – Humidity setpoint reset by outside air
temperature
Fig.12 – High humidity limit vs Control output level curve
Maximum Supply Humidity
100 %
0 %
50 %
Control
Output
Level
85 %