42/43
9.5.3 Fixed-hour rotation
A system consisting of both running and stand-by units is subject to unbalance in the working hours, causing
running units to age faster than stand-by ones. To obviate this problem, LAN network can provide for units
rotation, favouring balancing in the working hours. In practice, rotation sets a running unit to stand-by mode
and starts a stand-by unit.
The fixed-hour rotation is based on a parameter establishing the rotations time interval. The programmable
minimum time is 0h; in this case, automatic rotation enables every 5 minutes as a test. The maximum time is
240h (10 days). Time is counted from start-up of the unit with LAN address 1 that manages rotation.
Rotation can be executed following the LAN addresses logic or the units working hours.
Selecting the addresses logic, the unit with highest address (among the running ones) switches from on to
stand-by mode, whereas the unit withì lowest address switches from stand-by mode to on.
Selecting the working hours logic, the unit with highest working hours (among the running ones) switches
from on to stand-by mode, whereas the unit with lowest working hours switches from stand-by mode to on.
9.5.4 Fixed-day rotation
The clock card (optional) allows setting the hour and the days interval (max. 7) for units rotation. Logic is the
same as the fixed-hour rotation, but in this case the rotation interval can be programmed for a determined
day and hour.
9.5.5 Rotation based on working hours
This type of rotation involves the units with highest and lowest working hours, switching the former to stand-
by mode and the latter to On mode. The reference working hours for this type of rotation are the same as
the outlet fan ones; due to practical reasons, they can be modified in screens E6 and E7 of branch
Maintenance.
9.6 Master control
The units connected with LAN
network and in Present/… mode follow the working logic of the unit with
LAN
address 1, functioning as a “driver” unit so that the system can work with the same logic. This precaution
prevents units from having opposite logic, something that may occur in wide environments with different
temperatures or humidity areas. In such environments, each unit could follow the indications of the relevant
probe, causing the uncontrolled start of humidification, dehumidification, heating or cooling. This would
nullify their effect and cause energy waste.
WARNING
: the “driver” unit temperature and humidity probes must be located in an “intermediate” position
inside the controlled environment.
The “driver” unit sends the information concerning the logic to be adopted to the
LAN network. Therefore,
the network units found devices enabling on both reading of the relevant probes and “driver” unit order, so
that devices can turn on in case the two factors coincide.
The “driver” unit modifies the working logic in case the measured temperature or humidity exceed the set
point, even by few decimal points.
In case of black-
out or “driver” unit disconnection from
LAN network, the network units start functioning
independently again based on the relevant probes only.