DAB E.sybox Instrucciones Para La Instalación Y El Mantenimiento página 94

GB
ENGLISH
7.6.2 - T1: Low pressure delay (kiwa function)
Sets the time when the inverter switches off after receiving the low
pressure signal (see Setting low pressure detection par. 7.6.15.5). The
low pressure signal can be received on each of the 4 inputs by suitably
configuring the input (see Setup of auxiliary digital inputs IN1, IN2, IN3,
IN4 par 7.6.15).
T1 can be set between 0 and 12 s. The factory setting is 2 s.
7.6.3 - T2: Delay in switching off
Sets the delay with which the inverter must switch off after switch-off
conditions 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 charac-
terised by elasticity (for example with PVC pipes) and lowered in rigid
systems (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
adjustment, 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.
IMPORTANT: To obtain satisfactory pressure adjustments, you gener-
ally have to adjust both GP and GI
94
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 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 number 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 pres-
ent, 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.