DAB AD 1.0 AC, Instruction For Installation And Maintenance

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ENGLISH
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4. MULTI INVERTER SYSTEM
4.1 Introduction to multi inverter systems
A multi inverter system comprises a pump set made up of a series of pumps with delivery outlets all conveying to a single manifold.
Each pump of the set is connected to its own inverter and the various inverters communicate via a special connection (Link).
The maximum number of pump-inverter elements possible in a group is 8.
A multi inverter system is mainly used to:
•
Increase the hydraulic performance with respect to a single inverter
•
Ensure operation continuity in the event of a fault on a pump or inverter
• Partition maximum power
4.2 Setting up a multi inverter system
The pumps, motors and inverters in the system must be identical versions. The hydraulic system must be as symmetric as possible
in order to achieve a hydraulic load evenly distributed on all the pumps.
The pumps must all be connected to a single delivery manifold and the flow sensor must be placed on the outlet of the latter to read
the flow to the entire pump set. In the case of using multiple flow sensors, these must be installed on the delivery of each pump.
The pressure sensor must be connected to the outlet manifold. If more than one pressure sensor is used, these must also be installed
on the manifold or in any event on a pipeline that is connected to it.
If several pressure sensors are used, ensure that there are no check valves on the pipeline between one sensor and
another; otherwise different pressures may be read, leading to incorrect average readings and incorrect adjustments.
To ensure correct operation of the pressure set, the following must be identical for each inverter-pump pair:
• type of pump and motor
• hydraulic connections
•
rated frequency
•
minimum frequency
•
maximum frequency
•
the shutdown frequency without flow sensor
4.2.1 Communication cable (Link)
The inverters communicate with one another and propagate the flow and pressure signals (only if a ratiometric pressure sensor is
used) via the specific connection cable.
The cable can be connected to any one of the two connectors marked “Link”, see Figure 16.
Figure 18: Link connection