Application Types; Hydro Multi-B For Constant-Pressure Applications; Operating Principle; Control Variants - Grundfos Hydro Multi-B Instrucciones De Instalación Y Funcionamiento

4. Application types

Hydro Multi-B booster systems are available for the following
application types:
• constant-pressure boosting
• tank filling.
Furthermore, two control variants of the Hydro Multi-B are
available. The control variants are described below.

4.1 Hydro Multi-B for constant-pressure applications

The Hydro Multi-B system for constant-pressure applications is
designed to maintain a constant pressure on the discharge side
of the pumps. Hydro Multi-B systems for constant-pressure
applications adjust the performance according to the demand and
keep a constant pressure in the following ways:
• by cutting the required number of pumps in and out
• through continuous adjustment of the speed of the running
CME pumps.

4.1.1 Operating principle

The user enters the required pressure of the system (setpoint) via
the user interface of the CU 323 control unit. The CU 323 adjusts
the system performance according to the feedback received from
the pressure transmitter installed in the discharge manifold.

4.1.2 Control variants

Hydro Multi-B systems for constant-pressure applications are available as control variants E and ES.
Both systems work as described below.
Control variant E
Two to four electronically speed-controlled CME pumps.
One CME pump in operation.
H
H
set
Three CME pumps in operation.
H
H
set
• Control variant E for constant-pressure applications maintains a
constant pressure through continuous adjustment of the speed
of the pumps.
• The system performance is adjusted to the demand by cutting
the required number of pumps in and out and through parallel
control of the pumps in operation.
PT
Q
Q
Control variant ES
One to three mains-operated CM pumps and one
speed-controlled CME pump.
One CME pump in operation.
H
H
set
One CME pump and two CM pumps in operation.
H
H
set
• Control variant ES for constant-pressure applications maintains
a constant pressure through continuous adjustment of the speed
of the CME pump. The other pumps are cut in/out according to
demand and to achieve a performance corresponding to the
consumption.
• The CME pump always starts first and will be the last to stop.
If the pressure cannot be maintained by the pump, one or both
CM pumps will be cut in.
• Changeover among the mains-operated pumps is automatic and
depends on load, time and fault.
PT
Q
Q
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