4.2.2
Sensors
The sensors to be connected are the same versions used in stand-alone versions, i.e. pressure sensor and
flow sensor. Operation without a flow sensor is admitted on multi inverter systems.
4.2.2.1
Flow sensors
The flow sensor must be inserted on the delivery manifold on which all pumps are connected, and the
electrical connection can be made on any of the inverters.
The flow sensors can be connected in two ways:
one sensor only
the same number of sensors as inverters
The setting is entered on parameter FI.
Multiple sensors are useful when a specific flow rate is required on each pump, and enhance protection
against dry running operation. To use multiple flow sensors, parameter Fl must be set to multiple sensors
and each flow sensor must be connected to the inverter that controls the pump delivery where the sensor is
located.
4.2.2.2
Pressure sensors
The pressure sensor must be inserted on the delivery manifold. There can be more than one pressure
sensor, and in this case the pressure reading will be the average value of all those present. To use multiple
pressure sensors, the connectors are simply inserted in the relative inputs and no parameter needs to be
set. The number of pressure sensors installed can vary as required between one and the maximum number
of inverters present.
4.2.3
Connection and setting of the optical coupling inputs
The optical coupling inputs, see par. 2.2.4 and 6.6.13, are used to activate the float, auxiliary pressure,
system disabling and low suction pressure functions. The functions are indicated respectively by the
messages F1, Paux, F3, F4. If activated, the Paux function boosts the pressure in the system to the set
pressure, see par. 6.6.13.3. The functions F1, F3, F4 stop the pump for 3 different reasons, see par.
6.6.13.2, 6.6.13.4, 6.6.13.5.
When using a multi-inverter system, the optical coupling inputs must be used with the following precautions:
the contacts that perform the auxiliary pressures must be connected in parallel on all the inverters so
that the same signal arrives on all the inverters.
the contacts that perform the functions F1, F3, F4 may be connected either with independent
contacts for each inverter, or with only one contact connected in parallel on all the inverters (the
function is activated only on the inverter at which the command arrives).
The parameters for setting the inputs I1, I2, I3, I4 are part of the sensitive parameters, so setting one of
these on any inverter means that they are automatically aligned on all the inverters. As the setting of the
inputs not only selects the function, but also the type of polarity of the contact, the function associated with
the same type of contact will perforce be found on all the inverters. For the above reason, when using
independent contacts for each inverter (as is possible for the functions F1, F3, F4), these must all have the
same logic for the various inputs with the same name; that is, for the same input, either normally open
contacts are used for all the inverters or normally closed ones.
ENGLISH
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