DAB PUMPS PWM 203, Instruction For Installation And Maintenance

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Then, on the basis of parameters NA and NC it decides how many and which inverters must work at a given time. NA represents the
number of inverters involved in pumping NC represents the maximum number of
inverters that can run simultaneously.
In a series, if there are NA active inverters and NC simultaneous inverters, when NC is less than NA, this means that a maximum of
NC inverters will start up simultaneously, and these will switch between NA elements. If an inverter is configured with reserve priority,
it will set as last in the starting order, therefore for example, if there are 3 inverters and one of these is configured as reserve, the
reserve unit will start in third place; otherwise if set to NA=2 the reserve will not start up unless one of the two active units sets to
fault status.
See also the explanation of parameters
NA: Active inverters par. 6.6.8.1;
NC: Simultaneous inverters par. 6.6.8.2;
IC: Reserve configuration par. 6.6.8.3.
5. POWER-UP AND START-UP
5.1 Initial power-up operations
On correct completion of installation of the hydraulic and electrical system (see chapter 2 INSTALLAZIONE) and after reading the
entire manual, the inverter can be powered up. Only in the case of initial power-up, after the initial presentation, the display shows
the error condition "EC" with the message informing the user to set the parameters required for control of the electric pump; the
inverter does not start up. To unlock the unit, simply set the rated current value [A] of the electric pump used. Before start-up, if the
system pump requires special settings, other than the default versions (see par. 8.2) first make the modifications required and then
set the rated current value, to ensure start-up with the correct settings. The parameters can be set at any time, but it is
recommended to follow this procedure when the application is in operating conditions that may impair integrity of the system
components, such as in the case of pumps with a minimum frequency limit or do not tolerate certain dry running times etc.
The following steps apply both in the case of systems with a single inverter and multi-inverter systems. In the case of multi inverter
systems, the relative connections of sensors and communication cables must be made, after which one inverter at a time must be
activated, performing the initial power-procedure for each. Once all inverters are configured, all multi-inverter system elements can
be powered up.
5.1.1 Rated current settings
From the page displaying the message EC, or more in general from the main menu, access the Installer menu by pressing and
holding the buttons “MODE” & “SET” & “- ” simultaneously until “RC” appears on display. In these conditions, b and – enable
respectively increase and decrease of the parameter value. Set the current as specified in the manual or on the electric pump
dataplate (for example 8.0 A).
After setting the RC value and enabling it by pressing SET or MODE, if all elements have been installed correctly, the inverter starts
up the pump (unless error, blocking or protection conditions do not occur).
CAUTION: THE INVERTER STARTS UP THE PUMP AS SOON AS THE RC PARAMETER HAS BEEN SET.
5.1.2 Rated frequency settings
From the installer menu (if the RC value has just been entered, this is the same page; otherwise access as described in the above
section 5.1.1) press MODE and scroll through the menus to FN. Set the frequency using b and - as specified in the manual
or on the electric pump dataplate (for example 50 [Hz]).
Incorrect settings of the parameters RC and FN, or improper connections can generate the errors "OC", "OF"
and in the case of operation without the flow sensor, may generate the false errors "BL". Incorrect settings of
the parameters RC and FN can also cause failure of the current sensitivity protection device, leading to loads
exceeding the safety threshold of the motor, with consequent damage to the latter.
Incorrect configuration of the electric motor with star or delta connection may cause damage to the motor.
Incorrect configuration of the operating frequency of the electric pump can cause damage to the latter.