Hydro Multi-B For Tank-Filling Applications - Grundfos Hydro Multi-B Instrucciones De Instalación Y Funcionamiento

4.2 Hydro Multi-B for tank-filling applications

The Multi-B system for tank-filling applications is designed to fill
a tank such as a roof tank or a break tank in a controlled manner.
The Hydro Multi-B controls the filling either via level switches or
a level sensor.
4.2.1 Operating principle
The system has two methods of operation, one based on level
switches and the other on a level sensor.
Operation with level switches
The user adjusts the switches in the tank to the desired stop and
start levels.
Operation with level sensor
The user adjusts the setpoint so it corresponds to the real tank
height, measured from the bottom of the tank to the top, via the
user interface of the CU 323 control unit.
Factory setting
Start level: 15 % of setpoint
Stop level: 85 % of setpoint
High-level alarm: 95 % of setpoint.
4.2.2 Control variants
Hydro Multi-B systems for tank-filling applications are available as control variants E and ES. Both systems work as described below.
E: Two to four electronically speed-controlled CME pumps
ES: One to three mains-operated CM pumps and one speed-controlled CME pump
Pump speed
n
100 %
75 %
CME pump starts
Example of control variant ES
Fig. 3
• In tank-filling applications, the Hydro Multi-B fills the tank with focus on protecting the piping and preventing water hammer.
When low level in the tank is reached, a CME pump starts by running approximately 75 % of maximum speed in order to slowly and
safely fill the pipes. After a while, it increases the speed to 100 %, and the next pump is started. When the tank is full, the pumps
stop.
• Systems with more than two pumps will as default set one pump as standby pump.
• Changeover among the mains-operated pumps is automatic and depends on load, time and fault.
8
Control variants E and ES
CM pump starts CM pump stops
Time
t
CME pump stops