Multicircuit Management; Single Circuit Dry Cooler (V Shape With Spray System Evolution Or Emeritus®); Double Circuit Dry Cooler With Independent Set-Point - LU-VE Emeritus LU1W Manual De Usuario

In heat exchangers equipped with wet resources, up to 2 separate circuits can be operated. The two inputs dedicated
to the control probes are as follows:
•
circuit 1 = AI1
•
circuit 2 = AI2
Depending on the type of exchanger, different multi-circuit management logic is implemented. Multicircuit mode is
not implemented for SLAVE machines.
6.1
Spray System Evolution or EMERITUS® V-type exchangers may have a different number of sprays on either side of the
machine when sprayers (or sprayers + adiabatic panels) operate. This would result in a different heat exchange
capacity and thus a different water outlet temperature between the two coils. Consequently, each coil is equipped
with its own temperature probe; the setting detects both output temperatures and operates based on their average.
In the event of a failure of one of the two probes, the controller adjusts according to the working probe and returns a
failed probe warning. The failure of the second probe on AI2 is only reported if the probe is enabled; enable is
automatic according to the factory setting of parameter PG04 (see paragraph 6.2).
6.2
This is the case for liquid coolers with two operating circuits at different temperatures (low temperature circuit LT and
high temperature circuit HT), and placed in series on the air flow.
For each of the two circuits a probe is provided for obtaining the adjustment temperature, and a different reference
set-point is defined. The set-point for circuit 1 (analogue input probe AI1) is the already-seen parameter PR02 and the
set-point for circuit 2 (analogue input AI2 probe) is the PR20 parameter. The configuration parameter defining this
type of liquid cooler is parameter PG04.
The LU1W controller allows to assign, by parameter PG06, adjustment priority (and so the priority in defining the
resources required for cooling):
•
At one or the other circuit, i.e. it is possible to adjust the exchanger's resources according to regulation
temperature and set-point relative to one of the two circuits at user's choice (circuit 1 or circuit 2 priority);
•
To the circuit that requires more cooling resources (worse case) at the expense of cooling (also excessive)
that may occur on the other circuit. Adjustment is performed according to the circuit that has the greatest
deviation between the set point temperature and the effective liquid output temperature.
In the event of a failure of one of the two temperature probes, the adjustment is made only based on the circuit with
the active probe, and a failed probe warning is returned. Once the priority circuit is defined, the regulator acquires the
"adjustment temperature" and "reference set-point" of that circuit as "in use", and proceeds with the standard
algorithm.
LU1W - User Manual

6 MULTICIRCUIT MANAGEMENT

Single circuit dry cooler (V shape with Spray System Evolution or EMERITUS®)

Double circuit dry cooler with independent set-point

61 REV.1.1 – 07/11/2017 - ENG