DAB E.sybox 50, Instruction For Installation And Maintenance

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7.6.3 - T2: Delay in switching off
Sets the delay with which the inverter must switch off after switch-off con
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ditions have been reached: plant under pressure and flow rate lower than
the minimum flow.
T2 can be set between 2 and 120 s. The factory setting is 10 s.
7.6.4 - GP: Proportional gain coefficient
Generally the proportional term must be increased for systems character
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ised by elasticity (for example with PVC pipes) and lowered in rigid sys
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tems (for example with iron pipes).
To keep the pressure in the system constant, the inverter performs a type
PI control on the measured pressure error. Depending on this error the
inverter calculates the power to be supplied to the motor. The behaviour
of this control depends on the set GP and GI parameters. To cope with
the different behaviour of the various types of hydraulic plants where the
system can work, the inverter allows the selection of parameters different
from those set by the factory. For nearly all plants the factory-set GP and
GI parameters are optimal. However, should any problems occur in ad
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justment, these settings may be varied.
7.6.5 - GI: Integral gain coefficient
IIn the presence of large falls in pressure due to a sudden increase of the
flow or a slow response of the system, increase the value of GI. Instead,
if there are swings in pressure around the setpoint value, decrease the
value of GI.
7.6.6 - RM: Maximum speed
ISets a maximum limit on the number of pump revolutions.
7.6.7 - Setting the number of devices and of reserves
7.6.8 - NA: Active devices
Sets the maximum number of devices that participate in pumping.
It may have values between 1 and the number of devices present (max 4).
The default value for NA is N, that is the number of devices present in the
IMPORTANT:
To obtain satisfactory pressure adjustments, you gener
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ally have to adjust both GP and GI
chain; this means that if devices are added to or removed from the chain,
NA always has the value of the number of devices present, automatically
detected. If a number different from N is set, this fixes the maximum num
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ber of devices that can participate in pumping at the number set.
This parameter is used in cases where there is a limit on the pumps you
can or want to be able to keep running, and if you want to keep one or
more devices as a reserve (see 7.6.10 IC: Configuration of the reserve and
other examples below).
On the same menu page you can also see (but not change) the other two
system parameters linked to this, that is N, the number of devices present,
acquired automatically by the system, and NC, the maximum number of
simultaneous devices.
7.6.9 NC: Simultaneous devices
Sets the maximum number of devices that can work at the same time.
It may have values between 1 and NA. The default value of NC is NA, this
means that even if NA increases, NC will have the value NA. If a number
different from NA is set, this releases you from NA and fixes the maximum
number of simultaneous devices at the number set. This parameter is used
in cases where there is a limit on the pumps you can or want to be able
to keep running (see 7.6.10 IC: Configuration of the reserve and other
examples below).
On the same menu page you can also see (but not change) the other two
system parameters linked to this, that is N, the number of devices present,
read automatically by the system, and NA, the number of active devices.
7.6.10 IC: Configuration of the reserve
Configures the device as automatic or reserve. If set on auto (default) the
device participates in normal pumping, if configured as reserves, minimum
starting priority is associated with it, this means that the device with this
setting will always start last. If a number of active devices is set that is one
lower than the number of devices present and if one element is set as re
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serve, the effect obtained is that, if there are no problems, the reserve de
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vice does not participate in regular pumping; instead, if one of the devices
that participates in pumping develops a fault (maybe loss of power supply,
tripping of a protection, etc.), the reserve device will start.