DAB E.SYBOX MINI 3, Инструкция по установке и обслуживанию

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has a dual function: in the case of horizontal installation, the outlet that is closed by the cap
acts as the system’s loading door (see below “loading operations”, par. 2.2.3); in the case
of vertical installation, the same outlet can act as the input hydraulic connection (exactly
like the one marked “IN” on face C and as an alternative to it). The other 1” cap gives ac -
cess to a second delivery connection that can be used at the same time as or alternatively
to the one indicated with “OUT” on face C. The user interface panel is composed of a
display and a keyboard and its function is to set the system, query its status and com -
municate any alarms. The door closed by 2 screws gives access to a special maintenance
compartment: cleaning of the non-return valve and resetting of the tank preload pressure.
The system can be installed in 2 different configurations: horizontal (Fig.4) or vertical
(Fig.5).
1.1 Description of the Integrated Inverter
The electronic control integrated in the system is of the type with inverter and it makes use
of flow, pressure and temperature sensors, also integrated in the system.
By means of these sensors the system switches on and off automatically according to the
utility’s needs and it is able to detect conditions of malfunction, to prevent and indicate
them.
The Inverter control ensures different functions, the most important of which, for pumping
systems, are the maintaining of a constant pressure value in delivery and energy saving.
• The inverter is able to keep the pressure of a hydraulic circuit constant by varying the
rotation speed of the electropump. In operation without an inverter the electropump
is unable to modulate and, when there is an increase of the request for flow, the pres -
Figure 5
Figure 4
sure necessarily decreases, or vice versa; this means the pressures are too high at
low flow rates or too low when there is an increased request for flow.
• By varying the rotation speed according to the instantaneous request of the utility,
the inverter limits the power supplied to the electropump to the minimum necessary
to ensure that the request is satisfied. Instead, operation without an inverter contem -
plates operation of the electropump always and only at maximum power.
For the configuration of the parameters see chapters 4-5.
1.2 Integrated Expansion Vessel
The system is complete with an integrated expansion vessel with a total capacity of 1 litres.
The main functions of the expansion vessel are:
• to make the system elastic so as to protect it against water hammer;
• to ensure a water reserve which, in the case of small leaks, maintains the pressure in
the system for a longer time and spreads out needless restarts of the system which
otherwise would be continuous;
• when the utility is turned on, ensure the water pressure for the seconds that the
system takes to switch on and reach the correct rotation speed.
It is not a function of the integrated expansion vessel to ensure a water reserve such as to
reduce interventions of the system (requests from the utility, not from a leak in the system).
It is possible to add an expansion vessel with the capacity you prefer to the system, con -
necting it to a point on the delivery system (not a suction point!). In the case of horizontal
installation it is possible to connect to the unused delivery outlet. When choosing the tank,
consider that the quantity of water released will also depend on the parameters SP and RP
that can be set on the system (par. 4-5).
The expansion vessel is preloaded with pressurised air through the valve accessible from
the special maintenance compartment (Fig.1, Face F).
The preload value with which the expansion vessel is supplied by the manufacturer is in
agreement with the parameters SP and RP set as default, and anyway it satisfies the fol -
lowing equation:
Pair = SP – RP – 0.7 bar Where:
- Pair = air pressure value in bar
- SP = Set Point (par. 5.3.1) in bar
- RP = Reduction of pressure to restart