Grundfos HURLEY ENGINEERING Hydro Multi-B Series User manual

GRUNDFOS INSTRUCTIONS
Hydro Multi-B
Pressure boosting and tank fill applications
Installation and operating instructions
The Pacific Northwest's
premier Grundfos CBS
Manufacturer's Representative
for all Grundfos Booster
systems. Hurley Engineering
offers complete start up,
selection & installation
assistance, and has a full staff
of service technicians available
for preventive maintenance
programs. Hurley Engineering
is also the Pacific Northwest's
only Grundfos CBS Authorized
Service Partner.

English (US)
2
English (US) Installation and operating instructions
Original installation and operating instructions
These installation and operating instructions describe the
Grundfos Hydro Multi-B booster system.
Sections 1-5 give the information necessary to be able to unpack,
install and start up the product in a safe way.
Sections 6-17 give important information about the product, as
well as information on service, fault finding and disposal of the
product.
CONTENTS
Page
1. Limited Warranty
Products manufactured by GRUNDFOS PUMPS CORPORATION
(Grundfos) are warranted to the original user only to be free of
defects in material and workmanship for a period of 24 months
from date of installation, but not more than 30 months from date
of manufacture. Grundfos' liability under this warranty shall be
limited to repairing or replacing at Grundfos' option, without
charge, F.O.B. Grundfos' factory or authorized service station,
any product of Grundfos' manufacture. Grundfos will not be liable
for any costs of removal, installation, transportation, or any other
charges which may arise in connection with a warranty claim.
Products which are sold but not manufactured by Grundfos are
subject to the warranty provided by the manufacturer of said
products and not by Grundfos' warranty. Grundfos will not be
liable for damage or wear to products caused by abnormal
operating conditions, accident, abuse, misuse, unauthorized
alteration or repair, or if the product was not installed in
accordance with Grundfos' printed installation and operating
instructions.
To obtain service under this warranty, the defective product must
be returned to the distributor or dealer of Grundfos' products from
which it was purchased together with proof of purchase and
installation date, failure date, and supporting installation data.
Unless otherwise provided, the distributor or dealer will contact
Grundfos or an authorized service station for instructions. Any
defective product to be returned to Grundfos or a service station
must be sent freight prepaid; documentation supporting the
warranty claim and/or a Return Material Authorization must be
included if so instructed.
GRUNDFOS WILL NOT BE LIABLE FOR ANY INCIDENTAL OR
CONSEQUENTIAL DAMAGES, LOSSES, OR EXPENSES
ARISING FROM INSTALLATION, USE, OR ANY OTHER
CAUSES. THERE ARE NO EXPRESS OR IMPLIED
WARRANTIES, INCLUDING MERCHANTABILITY OR FITNESS
FOR A PARTICULAR PURPOSE, WHICH EXTEND BEYOND
THOSE WARRANTIES DESCRIBED OR REFERRED TO
ABOVE.
Some jurisdictions do not allow the exclusion or limitation of
incidental or consequential damages and some jurisdictions do
not allow limit actions on how long implied warranties may last.
Therefore, the above limitations or exclusions may not apply to
you. This warranty gives you specific legal rights and you may
also have other rights which vary from jurisdiction to jurisdiction.
1. Limited Warranty 2
2. Symbols used in this document 3
2.1 Warnings against hazards involving risk of death or
personal injury 3
2.2 Other important notes 3
3. Receiving the product 3
3.1 Transporting the product 3
4. Installing the product 3
4.1 Location 3
4.2 Mechanical installation 3
4.3 Electrical installation 5
5. Starting up the product 5
5.1 Positive inlet pressure startup procedure 5
5.2 Flooded suction and suction lift startup procedures 6
5.3 Handling the product 6
6. Product introduction 7
6.1 Product description 7
6.2 Applications 7
6.3 Identification 9
7. Control unit 10
8. Operating modes 12
8.1 Local mode, external stop not activated 12
8.2 Remote-controlled, external stop not activated 13
8.3 Remote-controlled, external stop activated 13
8.4 Adjusting the proportional-pressure setpoint 14
9. Functions 15
9.1 General functions 15
9.2 Functions for constant-pressure systems 15
9.3 Functions for tank-filling systems 17
10. Data communication 17
11. Servicing the product 17
11.1 Maintaining the product 17
12. Protecting the product against frost 17
13. Taking the product out of operation 17
14. Fault finding 18
15. Technical data 19
15.1 Pressure 19
15.2 Temperature 19
15.3 Relative humidity 19
15.4 Sound pressure level 19
15.5 Electrical data 19
16. Related documents 20
16.1 Service documentation 20
17. Disposing of the product 20
Read this document before installation. Installation
and operation must comply with local regulations and
accepted codes of good practice.
This appliance can be used by children aged from 8
years and above and persons with reduced physical,
sensory or mental capabilities or lack of experience
and knowledge if they have been given supervision
or instruction concerning use of the appliance in a
safe way and understand the hazards involved.
Children shall not play with the appliance. Cleaning
and user maintenance shall not be made by children
without supervision.

3
English (US)
2. Symbols used in this document
2.1 Warnings against hazards involving risk of death
or personal injury
2.2 Other important notes
3. Receiving the product
3.1 Transporting the product
The booster system is delivered in a recyclable packaging,
specially designed for transport by forklift truck or a similar
vehicle.
The forks of the forklift truck must be at least 6.6 ft (2 m) long.
4. Installing the product
Before installing the product, check the following:
• The booster system corresponds to the order.
• All visible parts are intact.
4.1 Location
Install the booster system in a well-ventilated room to ensure
sufficient cooling of the control cabinet and pumps.
Place the booster system with a 3.3 ft (1 m) clearance on all sides
for inspection and removal.
4.2 Mechanical installation
4.2.1 Pipes
Connect the pipes to the manifolds of the booster system. Either
end can be used. Apply sealing compound to the unused end of
the manifold, and fit the screw cap. For manifolds with flanges, fit
a blanking flange with gasket.
We recommend that you install pipe supports for the inlet and
outlet pipes. See figs 1and 2.
Noise and vibration are generated by the rotations in the motor
and pump and by the flow in pipes and fittings. The effect on the
environment is subjective and depends on correct installation and
the state of the other parts of the system.
If booster systems are installed in blocks of flats or the first
consumer on the line is close to the booster system, we
recommend that you fit expansion joints on the inlet and outlet
pipes to prevent that vibrations are transmitted through the pipes.
DANGER
Indicates a hazardous situation which, if not avoided,
will result in death or serious personal injury.
CAUTION
Indicates a hazardous situation which, if not avoided,
could result in minor or moderate personal injury.
SIGNAL WORD
Description of hazard
Consequence of ignoring the warning.
- Action to avoid the hazard.
If these instructions are not observed, it may result in
malfunction or damage to the equipment.
Tips and advice that make the work easier.
A red or grey circle with a diagonal bar, possibly with
a black graphical symbol, indicates that an action
must not be taken or must be stopped.
The booster system is designed for indoor
installation. Do not expose the product to direct
sunlight.
The pipes connected to the booster system must be
of adequate size.

English (US)
4
Fig. 1 Example showing the position of expansion joints, pipe
supports and machine shoes
Fig. 2 Example showing the position of expansion joints, pipe
supports and mounting bolts
Tighten all nuts before startup.
Fasten the pipes to parts of the building to ensure that they
cannot move or be twisted.
4.2.2 Foundation
Position the booster system on an even and solid surface, for
instance a concrete floor or foundation. The booster system must
be bolted to the floor or foundation.
4.2.3 Vibration dampers
To prevent the transmission of vibrations to buildings, it may be
necessary to isolate the booster system foundation from building
parts by means of vibration dampers.
The right damper varies from installation to installation, and a
wrong damper may increase the vibration level. Vibration
dampers must therefore be sized by the supplier. If the booster
system is installed on a base frame with vibration dampers,
always fit expansion joints on the manifolds. This is important to
prevent the booster system from "hanging" in the pipes.
4.2.4 Expansion joints
Fit expansion joints for these reasons:
• to absorb expansions or contractions in the pipes caused by
changing liquid temperature
• to reduce mechanical strains in connection with pressure
surges in the pipes
• to isolate mechanical structure-borne noise in the pipes (only
rubber bellows expansion joints).
Fit expansion joints at a distance of minimum 1 to 1 1/2 times the
nominal flange diameter from the manifold on the inlet as well as
on the outlet side. This prevents the development of turbulence in
the expansion joints, resulting in better inlet conditions and a
minimum pressure loss on the outlet side.
Fig. 3 Examples of rubber bellows expansion joints without
and with limiting rods
TM03 2154 3805
Pos. Description
1 Expansion joint (and good location for isolating valves)
2 Pipe support
3 Machine shoe
TM04 9900 0211
Pos. Description
1 Expansion joint (and good location for isolating valves)
2 Pipe support
3 Mounting bolt
Expansion joints, pipe supports as well as machine
shoes or mounting bolts shown in figs 1and 2
respectively are not included in a standard booster
system.
2
11
33
2
The weight of a concrete foundation must be 1.5
times the weight of the booster system.
Do not install expansion joints to compensate for
inaccuracies in the pipes such as center
displacement of flanges.
TM02 4981 1902 - TM02 4979 1902

5
English (US)
Expansion joints with limiting rods can be used to minimise the
forces caused by the expansion joints. We always recommend
that you use expansion joints with limiting rods for flanges larger
than ANSI 4" (DN 100).
Anchor the pipes so that they do not stress the expansion joints
and the pump. Follow the supplier’s instructions and pass them
on to advisers or pipe installers.
4.2.5 Prefilling of diaphragm tank, if applicable
If a diaphragm tank is connected to the system, prefill the tank
with nitrogen to a pressure of 0.7 times the setpoint.
4.3 Electrical installation
• The electrical installation of the booster system must comply
with enclosure class UL type 3R.
• Check that the power supply and frequency correspond to the
values stated on the nameplate.
• Make sure that the conductor cross-section meets the
specifications in the wiring diagram.
5. Starting up the product
After having carried out the mechanical, electrical and hydraulic
installation described in sections 4.2 Mechanical installation,
4.3 Electrical installation, proceed as follows:
5.1 Positive inlet pressure startup procedure
1. Check that the precharge pressure in the diaphragm tank is
0.7 times the required outlet pressure (setpoint).
2. Close all pump outlet isolation valves on the Multi B system.
3. Open the outlet valve on one pump and turn the tap on the
outlet side of the system allowing water to pass through the
pump. Once complete, close the isolation valve.
4. Repeat step 3 for all remaining pumps in the system. Once
complete, open the outlet isolation valve on all pumps after all
pumps have been vented.
5. Switch on the main switch.
6. Turn the system on by pressing [On/Off] and adjust the
setpoint to the desired setpoint value by pressing arrow up or
arrow down on the controller.
Use nitrogen to avoid corrosion.
CAUTION
Electric shock
Minor or moderate personal injury
- The electrical installation must be carried out by an
approved person in accordance with local
regulations and the relevant wiring diagram.
- Switch off the power supply and lock the main
switch with a padlock to ensure that the power
supply cannot be accidentally switched on.
See the wiring diagram supplied with the booster
system. Tighten all wire terminals in the panel before
switching on power to the panel.
If the system cannot be installed with the supply
disconnecting device located minimum 2 ft (0.6 m)
above service level according to EN 60204-1
paragraph 5.3.4, install the system with an external
"supply disconnecting device" made according to EN
60204-1, paragraph 5.3.2. The system must be
provided with a means permitting it to be locked in
the OFF (isolated) position.
A positive inlet pressure is required before startup
and during operation.
Do not start the pumps until they have been fully
primed.
Set the precharge pressure on the diaphragm tank
with zero pressure on the tank.
Measure the precharge pressure in the diaphragm
tank while the system is not pressurized.

English (US)
6
5.2 Flooded suction and suction lift startup
procedures
1. Check that the precharge pressure in the diaphragm tank is
0.7 times the required outlet pressure (setpoint).
Note: Set the precharge pressure with zero pressure on the
tank.
2. Switch off the main switch on the cabinet front.
3. Switch off the circuit breakers of all pumps. The circuit
breakers are located inside the cabinet.
4. Set the "Emergency/Normal" switch for all pumps to
"Emergency". The switch is located on the front of the control
cabinet.
5. Close all pump outlet valves and prime all pumps. Prime the
pumps by opening the cap on the port of the check valve
positioned closest to the pump and filling water into the port.
Prime the pump when water no longer is able to fill into the
pump. Reinstall the cap on the check valve port and repeat
the procedure for all pumps.
6. Switch on the relevant circuit breaker of the pump to be
started.
7. Switch on the main switch; this will start the pump with the
relevant circuit breaker on.
8. Vent the pump by slowly opening the outlet valve. This will
also allow gradual filling of the outlet pipes.
9. Set the "Emergency/Normal" switch for the relevant pump to
"Normal".
10. Switch off the main switch.
11. Repeat steps 6, 7, 8, 9 and 10 for the other pumps in the
system.
12. Switch on the main switch.
13. Adjust the required setpoint via the CU 323 by pressing arrow
up or arrow down.
14. Set the system to "On" by pressing [On/Off].
15. Increase the setpoint to the desired setpoint value.
Hydro Multi-B is now in automatic mode and ready for operation.
5.3 Handling the product
Lift the booster systems with CM and CME pumps as shown in
fig. 4.
During handling, the lifting point must always be above the center
of gravity of the booster system.
Fig. 4 Correct lifting of Hydro Multi-B with CM and CME
pumps
When lifting the booster system, only use suitable lifting
equipment that is in good condition and approved for the weight.
The weight is stated on the nameplate of the booster system.
Measure the precharge pressure in the diaphragm
tank while the system is not pressurized.
If you change the outlet pressure, change the
diaphragm tank precharge pressure accordingly.
The initial setpoint pressure value for the system is 0
psi, and the maximum pressure is 22 psi above the
setpoint value.
This may cause a "Maximum pressure exceeded"
alarm condition after startup is complete. Increase
the setpoint pressure value to the desired pressure
and, if necessary, bleed off the pressure on the outlet
to clear the "Maximum pressure exceeded" fault.
TM05 0221 0911
CAUTION
Overhead load
Minor or moderate personal injury
- When lifting the booster system, do not use the
eyebolts of the motors.
- Do not lift the booster system by the manifolds.
- Do not stand on the manifolds.
CAUTION
Crushing of feet
Minor or moderate personal injury
- When lifting the booster system, do not use the
eyebolts of the motors.
- Do not lift the booster system by the manifolds.
- Do not stand on the manifolds.

7
English (US)
6. Product introduction
6.1 Product description
Hydro Multi-B is a range of factory-assembled pump systems,
ready for installation and operation.
As standard, the booster systems consist of two and three pumps
connected in parallel and mounted on a common base frame with
a control cabinet and all necessary fittings.
Fig. 5 Front view of Hydro Multi-B booster system with three
CM(E) pumps
Fig. 6 Rear view of Hydro Multi-B booster system with three
CM(E) pumps
6.2 Applications
The booster systems are suitable for the following application
types:
• constant-pressure boosting
• tank filling.
6.2.1 Booster system for constant-pressure applications
The booster system for constant-pressure applications is
designed to maintain a constant pressure on the outlet side of the
pumps. The booster 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
pumps.
Operating principle
The user enters the required pressure of the system (setpoint) via
the user interface of the CU 323 control unit. CU 323 adjusts the
system performance according to the feedback received from the
pressure transmitter installed in the outlet manifold.
TM04 9898 0211TM04 9899 0211
Pos. Description Quantity
1 Control cabinet 1
2 Inlet manifold 1
3 Outlet manifold 1
4 Diaphragm tank (not included) 1
5 Isolating valve 2 per pump
6 Non-return valve 1 per pump
7Pump 2-4
8 Base frame 1
9 Pressure transmitter and pressure gauge 1
10 Pressure switch or inlet pressure sensor 1
11 Oval flange (CME 3-10) 2 per pump
Intermediate adapter (CME 15-25) 1 per pump
12 Screw cap or blanking flange 2
12
11
9

Control variant E
Two to three electronically speed-controlled pumps
TM03 0993 0905
One speed-controlled pump in operation.
TM00 7995 2296
Three speed-controlled pumps in operation.
TM00 7996 2296
• 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
H
Hset
Q
H
Hset

English (US)
8
6.2.2 Booster system for tank-filling applications
The booster 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 booster system controls the filling either via level switches, a
level sensor, or a ball cock valve.
• Operating principle
The system has three methods of operation, one based on
level switches, one based on a level sensor and the other
based on a ball cock valve.
• 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.
• Operation with ball cock valve
The user adjusts the ball cock valve in the tank to the desired
start and stop levels.
• Factory setting
Start level: 15 % of setpoint
Stop level: 85 % of setpoint
High-level alarm: 95 % of setpoint.
The Multi-B systems configured for tank filling applications work as described below.
The CU323 will display the tank level graphically. For
assistance contact Grundfos.
The PC tool is required to adjust the start and stop
level setting. For assistance contact Grundfos.
Control variant E
E: Two to three electronically speed-controlled pumps
TM05 0222 0911
Fig. 7 Example of tank filling
• In tank-filling applications, the booster system fills the tank with focus on protecting the piping and preventing water hammer. When
low level in the tank is reached, a speed-controlled pump starts by running approximately 70 % of maximum speed 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.
First pump starts Second pump starts First pump stops
Second pump stops
Time
Pump speed
t
n
100 %
70 %

9
English (US)
6.3 Identification
6.3.1 Nameplate
The nameplate of the booster system is fitted on the base frame.
Fig. 8 Nameplate
6.3.2 Type key
* The control cabinet can be placed up to 6.6 ft (2 m) from the pumps.
TM06 9434 2317
Pos. Description
1 Type designation
2 Model
3 Serial number
4 Supply voltage
5 Maximum operating pressure in psi
6 Liquid temperature
7 Panel part number
8 Weight in lb
9 Country of origin
10 Company logo
11 Maximum flow rate in GPM
12 Nominal head in ft
13 Approval mark, cULus (Category QCZJ)
14 Approval mark
15 QR code
Type: HYDRO MULTI-B 3 CME10-3
Model: A
Serial No.: 10000001
Mains supply: 3 x 460 V, 60 Hz
pMax: 145 PSI Q Nom / Max: 159 / 240
H Nom / Max: 127 / 225Liq. temp.: 32-140
Panel PN: 91148011
Weight: 840 Ib
ASSEMBLED IN US
ft
GPM
F
QR
code Packet Pumping system 38PK
DK - 8850 - Bjerringbro - Denmark
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
Code Example Hydro Multi-B -E 3 CME 10-3 A 3 x 460 V, 60 Hz
Type range
E
System type
All pumps, E-motor or CUE
Number of pumps with integrated frequency drive and pump type
A
Pump material
Cast iron (EN-GJL-200)
Supply voltage, frequency

English (US)
10
7. Control unit
The booster system incorporates a CU 323 control unit which enables manual setting and monitoring of the system.
Figure 9shows the user interface for a system with four pumps.
Fig. 9 User interface of control cabinet and CU 323
TM05 0479 1111
PT
WS
On
Off
RESET
OFF AUTO
OFF AUTO
OFF AUTO
OFF AUTO
CU 323
4
3
2
1
system run
alarm
1
2
3
4
5
8
9
10 11
12
13
14
15
16
PT
WS
On
Off
RESET
OFF AUTO
OFF AUTO
OFF AUTO
OFF AUTO
CU 323
4
3
2
1
system run
alarm
6
7
Pos. Buttons Description
1 [On/Off]: Changes the system operating mode between "Normal" and "Stop".
2 [Up]: Increases the setpoint value.
3 [Down]: Decreases the setpoint value.
4 [RESET]: Resets all alarms.
5[>]: Changes the operating mode of the individual pumps between "AUTO" and "OFF". Each pump in
the system has an Auto/Off button.
6
Enables "Emergency/Normal" operation.
Note: If a pump is set to "Emergency" operation, it will run at 100 % speed, and the power supply to
CU 323 will be switched off. There is a delay of 30 seconds before the pumps are set to "Emergency"
operation.
7 Switches the power supply to the control cabinet on or off.
8
"Setpoint" Shows the setpoint. After unlocking CU 323, the setpoint will flash.
Proportional-pressure control. "PPP" flashes for one second followed by the current setpoint for four
seconds. This function is only available for E-pump systems.
The tank symbol appears in tank-filling mode with float switches.
or "Setpoint" Alternates between the tank symbol and the setpoint in tank-filling mode with analog input.
External stop: Indicates that the system has been stopped externally via a digital input.
Indicates that the system has been set to "OFF".
Indicates that the system has been set from "OFF" to "On". "On" is only shown for 3 seconds after
which the setpoint is shown.
Indicates that the buttons on CU 323 have been locked automatically. To unlock the buttons, press
[RESET] and arrow up or [RESET] and arrow down simultaneously.
Indicates that the system is remotely controlled.
Local: Appears if attempts to change local settings are made while the system is remotely controlled.
On
Off
RESET
1___!
1___!
E.St
OFF
On
0-N
bUS
LOC

11
English (US)
* The last pump in operation might have been stopped temporarily by the low-flow stop function
Optional Tank level indicator lights
Indicator lights correspond to the float switch position
9
"Measured value" Shows the actual, measured value on the outlet side.
Proportional setpoint at zero flow, PPS [psi]. "PPS" is visible if you press [RESET] for four seconds.
After [RESET] has been released, you can adjust "PPS" by means of the arrow up or arrow down
buttons. If the buttons are not activated for four seconds, the system returns to normal operation.
This function is only available for E-pump systems.
Appears in tank-filling mode with float switches.
Appears in case of a primary sensor fault.
or "Measured value"
Alternates between the actual, measured value on the outlet side and "H.L" when a maximum outlet
pressure or a level limit has been exceeded.
Pos. Buttons Description
336
---
Err
H.L
Pos. Indicator
lights Status Description
10 Off Normal state.
Red Water shortage fault.
11
Off Normal state.
Red Primary and/or redundant sensor fault.
Maximum discharge pressure or level limit has been exceeded.
12
(pump LED)
Off
The pump has stopped due to cascade operation.
The system is in "OFF" state.
The power supply has been switched off.
Red A pump fault has occurred.
Green The pump is running.
Flashing green The pump is in standby mode or has been stopped by pressing [>] or via remote control.
13 AUTO Yellow The pump is controlled by the CU 323.
14 OFF Yellow The pump has been stopped by pressing [>] or via remote control.
WS
PT
Pos. Indicator
lights
Status
Description
Pos. 15:
system run
(green)
Pos. 16:
alarm
(red)
15 and 16
(system LEDs)
Off Off The power supply has been switched off.
On Off The system is in normal operation.*
Flashing Off The system has been set to stop.
Off On The system has been stopped due to an alarm.
On On The system is in normal operation, but there is a warning.*
Flashing On The system has been set to stop, and there is a warning.
Pos. Indicator
lights Status Description
Not
shown (High level)
On Tank level is high.
Off Tank level is normal.
Not
shown
(Low level)
On Tank level is low
Off Tank level is normal

English (US)
12
8. Operating modes
User operation depends on the system mode. The system modes are described in the following sections.
8.1 Local mode, external stop not activated
In this mode, the system is locally controlled, and the external stop via digital input is not activated.
The flow charts below show examples of how settings can be made.
Starting and stopping the system
Changing the setpoint while the system is running
Changing the setpoint while the system is in "OFF" mode
Local mode, external stop activated
In this mode, the system is locally controlled, and the external stop via digital input is activated.
External stop via digital input has higher priority than local control. This means that settings can be changed locally, but they will not be
effective until external stop has been deactivated. The flow charts below show examples of how settings can be made
Starting and stopping the system
TM05 9701 4313
On
Off
On
Off
Starting the system Stopping the system
TM05 9284 3613
Changing the setpoint
TM05 9285 3613
Changing the setpoint
or
TM04 9580 4610
E.st
OFF
OFF
ON
ON
On
Off
On
Off
On
Off
Starting the system
Stopping the system
If you do not touch the buttons for 3 seconds, CU 323
reverts to the initial display.

13
English (US)
Changing the setpoint
8.2 Remote-controlled, external stop not activated
In this mode, the system is remote-controlled, and the external stop via digital input is not activated.
If you want to change the local settings, follow the flow chart examples below.
8.3 Remote-controlled, external stop activated
In this mode, the system is remote-controlled, and the external stop via digital input is activated.
If you want to change the local settings, follow the flow chart examples below.
TM05 9286 3613
Changing the setpoint
or
If you do not touch the buttons for 3 seconds, CU 323
reverts to the initial display.
TM04 9582 4610
Keep the buttons pressed for 3 seconds.
See section 8.1 Local mode,
external stop not activated for
changing settings in local mode.
or or
or
or
or
If you do not touch the buttons for 3 seconds, CU 323
reverts to the initial display.
TM04 9583 4610
BUS LOC
E.st
On
Off
On
Off
Keep the buttons pressed for 3 seconds.
See section Local mode, external
stop activated for changing settings
in local mode.
or or
or or
If you do not touch the buttons for 3 seconds, CU 323
reverts to the initial display.

English (US)
14
8.4 Adjusting the proportional-pressure setpoint
Description
You can only enable this function in pressure-controlled systems.
The function automatically adapts the setpoint to the actual flow
rate to compensate for flow-dependent dynamic losses.
The adaptation can only be square. See fig. 10.
Fig. 10 Proportional pressure
The function has these purposes:
• compensate for pressure losses
• reduce the energy consumption
• increase the comfort for the user.
Activating the function through PC Tool E-products
Settings > Primary controller.
1. Select: Enabled proportional pressure.
2. Set: Influence at zero flow.
3. Set: Filter factor.
4. Select: Hmax / Enter value. Based on pump data.
5. Select: Qnom / Enter value. Based on pump data.
6. Select: Hnom / Enter value. Based on pump data.
Activating the function via the operating panel
This is only applicable when the function is enabled in PC Tool
E-products.
1. Press [RESET] for 4 seconds. Let go of the button when the
text "PPS" appears in the display.
2. Adjust the "PPS" value with the arrow up and arrow down
buttons.
A filter factor can be set to prevent fluctuation.
TM06 2845 4714
Pos. Description
A
Pressure at zero flow.
Starting point of proportional-pressure control.
Influence at zero flow is equal to x % of the setpoint.
BQnom
CSetpoint
H
C
A
B
Q
TM06 5417 4515
.336
.
.
RESET
Keep the buttons pressed for 4 seconds.
See section Local mode,
external stop activated for
changing settings in local mode.
The "PPS" value is defined in psi at zero flow.

15
English (US)
9. Functions
The booster systems include application-optimized software.
9.1 General functions
9.1.1 Dry-running protection (optional)
To protect the pumps against damage from dry running, the
booster system incorporates a water shortage function. This
function is based on the monitoring of the inlet pressure or the
level in a possible tank on the inlet side.
The pressure or level can be monitored by one of the following
devices:
• pressure switch
• float switch
• level switch
• external electrode relay
• analog sensor.
Dry-running protection with pressure switch, float switch,
level switch or external electrode relay
Set the monitoring device to the desired limit.
If a water shortage is detected for more than 5 seconds, the
system will stop, and the "WS" water shortage indicator light is
on.
When the water supply has been reestablished, the dry-running
fault is automatically reset.
Dry-running protection with analog sensor
The limit for the minimum inlet pressure in the inlet manifold is a
factory-set value which can only be changed by a Grundfos
service engineer.
If the sensor output is below the limit for minimum inlet pressure
for more than 5 seconds, the system will stop, and the "WS"
water shortage indicator light is on.
When the water supply has been reestablished, the dry-running
fault is automatically reset.
9.1.2 Automatic pump changeover
The automatic pump changeover function ensures an equal
number of operating hours of the pumps, but it also ensures that,
in case of an alarm on one pump, another pump is automatically
started.
There are three types of automatic pump changeover:
• operation-dependent pump changeover
• alarm-dependent pump changeover
• time-dependent pump changeover.
Alarm-dependent pump changeover
If a pump stops due to an alarm, CU 323 will send a stop
command to the pump to prevent auto-restarting and start
another pump which is ready to start and which has the lowest
number of operating hours.
Time-dependent pump changeover
In certain applications, the demand remains constant for long
periods and does not require all pumps to run. In such situations,
pump changeover does not take place naturally, and forced pump
changeover may thus be required.
Once every 24 hours, CU 323 checks if any of the running pumps
has a higher number of operating hours than the pumps that are
stopped. If this is the case, the pump will be stopped, and a pump
with a lower number of operating hours will start.
9.1.3 Minimum time between start and stop
This function ensures a delay between the start/stop of one pump
and the start/stop of another pump. The purpose is to prevent
hunting when pumps start and stop continuously.
9.2 Functions for constant-pressure systems
9.2.1 Pump cascade control
The cascade function ensures that only the required number of
pumps is running. This means that the number of running pumps
always corresponds to the required flow at the entered setpoint.
The first pump is started if the pressure at the outlet manifold is
below the setpoint.
If the first pump is not able to keep the outlet pressure at the
setpoint, and the minimum time between start/stop has passed,
another pump is started.
During the start and stop of a pump, the speed of the
speed-controlled pump is controlled in such a way that the
pressure disturbance is kept as low as possible.
At decreasing demand, pumps will be stopped if the pressure
rises above the setpoint. Pumps will not be stopped until the
minimum time between start/stop has passed.
The last pump in operation
If only one pump is operating, this pump can be operated in
energy-saving on/off mode. See section 9.2.4 Low-flow
operation.
The number of possible starts/stops per hour for all pumps is
limited by the maximum number of starts per hour.
When a pump is running in manual mode, it is not
protected against dry running.
If the speed-controlled pump in an ES system is
stopped due to an alarm, the system will function as
an S-system.
See section 9.2.5 S-system mode (start/stop band).
If the system is stopped due to an alarm, the
minimum time between start and stop will be ignored,
and the pumps will be stopped immediately.

English (US)
16
9.2.2 Standby pumps
This function is optional and available on request. The function
makes it possible to limit the maximum performance of the
booster system by selecting one or more pumps as standby
pumps.
If a three-pump system has one standby pump, maximum two
pumps are allowed to operate at a time.
If one of the two pumps in operation has a fault and is stopped,
the standby pump will be started. The performance of the booster
system is thus not reduced.
The status as standby pump alternates between all pumps.
Contact Grundfos for further information.
9.2.3 Maximum pressure exceeded
This function protects the piping on the outlet side of the booster
system against damaging high pressures. The pressure is
monitored, and if the pressure is higher than 22 psi (1.5 bar)
above the setpoint for more than 5 seconds, the pumps are
stopped, the indicator light "PT" is on, and the display indicates
high limit "H.L".
When the pressure falls below the setpoint, the system will
automatically restart.
9.2.4 Low-flow operation
When only one pump is operating due to cascade, the booster
system regularly checks for low flow by decreasing the pump
speed.
When low flow is detected, the booster system will change its
mode of operation to "low-flow operation" and run in on/off mode
as described below.
In on/off mode, the system has two phases:
• Off phase
Water is drawn from the diaphragm tank until the pressure of
the system reaches the lower limit of the on/off band (Pset -
0.5 x on/off band).
• Boosting phase
The pump runs at 100 % speed until the pressure reaches the
upper limit of the on/off band (Pset + 0.5 x on/off band).
Fig. 11 On/off operation
9.2.5 S-system mode (start/stop band)
S-system mode is only auto-enabled in an ES system if the CME
pump is out of operation due to a fault.
Fig. 12 Start/stop band
9.2.6 Proportional-pressure control mode
The proportional-pressure control mode is only available for
E-pump systems.
Description
You can only enable this function in pressure-controlled systems.
The function automatically adapts the setpoint to the actual flow
rate to compensate for flow-dependent dynamic losses.
The adaptation can only be square. See fig. 13.
Fig. 13 Proportional pressure
The function has these purposes:
• compensate for pressure losses
• reduce the energy consumption
• increase the comfort for the user.
TM03 9292 4807
Stop: Hset + 0.5 x on/off band
Start: Hset - 0.5 x on/off band
Stop
Start
H [m]
Time [s]
AB C B C
A: Normal operation
B: Pressure boosting
C: Stop
TM03 9205 3607
A filter factor can be set to prevent fluctuation.
TM06 2845 4714
Pos. Description
A
Pressure at zero flow.
Starting point of proportional-pressure control.
Influence at zero flow is equal to x % of the setpoint.
BQnom
CSetpoint
Start/stop band
Hset
Time [s]
H [m]
Pump stops
Pump starts
H
C
A
B
Q

17
English (US)
Activating the function through PC tool E-products
Settings > Primary controller.
1. Select: Enabled proportional pressure.
2. Set: Influence at zero flow.
3. Set: Filter factor.
4. Select: Hmax / Enter value. Based on pump data.
5. Select: Qnom / Enter value. Based on pump data.
6. Select: Hnom / Enter value. Based on pump data.
Activating the function via the operating panel
This is only applicable when the function is enabled in PC Tool
E-products.
1. Press [RESET] for 4 seconds. Let go of the button when the
text "PPS" appears in the display.
2. Adjust the "PPS" value with the arrow up and arrow down
buttons.
9.3 Functions for tank-filling systems
9.3.1 Cascade control
The cascade control function for tank-filling systems is designed
to fill the tank with focus on protecting the piping and preventing
water hammer. The cascade is time-dependent and starts and
stops the pumps in a pre-defined sequence. See fig. 7on page 8.
9.3.2 Standby pumps
Systems with more than two pumps will as default set one pump
as standby pump.
The status as standby pump alternates to ensure that all pumps
have equal numbers of operating hours.
9.3.3 Maximum level exceeded
This function protects against the risk of overfilling the tank. The
level is monitored and if the level is higher than 95 % of the height
of the tank, the pumps are stopped; the display indicates high
limit "H.L", and the "PT" indicator light is on.
9.3.4 Optional tank fill application panels
Optional panels include indicator lights controlled by float
switches that indicate if the high or low level is exceeded with
80 dB alarm.
10. Data communication
CU 323 must have a CIM module (Communication Interface
Module) fitted to be able to transfer data to the SCADA system or
to a mobile phone.
Various CIM modules are available, depending on the type of
network. See the Hydro Multi-B data booklet or contact Grundfos
for further information regarding CIM modules.
11. Servicing the product
11.1 Maintaining the product
11.1.1 Pumps
The internal pump parts are maintenance-free. It is important to
keep the motor clean in order to ensure adequate cooling of the
motor. If the pump is installed in dusty environments, clean and
check it regularly. Take the enclosure class of the motor into
account when cleaning.
The motor has maintenance-free, greased-for-life bearings.
11.1.2 CU 323
CU 323 is maintenance-free. It must be kept clean and dry.
Protect it against direct sunlight. Furthermore, CU 323 must not
be outside the ambient temperature range. See section
15. Technical data.
12. Protecting the product against frost
If pumps are not used during periods of frost, they must be
drained to avoid damage.
Follow these instructions:
1. Close the isolating valves before and after the pump.
2. Remove the filling and drain plugs.
3. Open the isolating valves and refit the plugs before the pump
is put into operation again.
Do not fit the filling and drain plugs until the pump is to be used
again.
13. Taking the product out of operation
Switch off the main switch to take the booster system out of
operation.
Take individual pumps out of operation by switching off the
corresponding motor-protective circuit breaker, automatic circuit
breaker or fuse.
The "PPS" value is defined in psi at zero flow.
WARNING
Electric shock
Death or serious personal injury
- Switch off the power supply before you start any
work on the product.
- Lock the main switch with a padlock to ensure that
the power supply cannot be accidentally switched
on.
WARNING
Electric shock
Death or serious personal injury
- Make sure that the escaping hot or cold liquid does
not cause injury to persons or damage to the
equipment.
- In hot-water installations, pay special attention to
the risk of injury caused by scalding hot water.
WARNING
Electric shock
Death or serious personal injury
- Do not touch the conductors in front of the main
switch as they are still energized.
- Lock the main switch with a padlock to ensure that
the power supply cannot be accidentally switched
on.

English (US)
18
14. Fault finding
WARNING
Electric shock
Death or serious personal injury
- Switch off the power supply for at least five
minutes before you start any work on the product.
- Make sure that the power supply cannot be
accidentally switched on.
Fault Possible cause Remedy
1. The pumps are not
running.
a) The actual pressure is higher than or
equal to the setpoint.
Wait until the pressure has dropped, or lower the pressure
on the outlet side of the booster system. Check that the
pumps start.
b) The power supply has been switched off. Connect the power supply.
c) The main switch has cut out. Cut in the main switch.
d) The main switch is defective. Replace the main switch.
e) The motor protection has been
activated. Contact Grundfos.
f) The motor is defective. Repair or replace the motor.
g) The pressure transmitter is defective. Replace the pressure transmitter.
0-145 psi (0-10 bar) transmitters with 0-10 V, 0-20 mA or
4-20 mA output signals are monitored by the booster
system.
h) The cable is broken or short-circuited. Repair or replace the cable.
2. The pumps start, but
stop immediately. The
operating pressure is
not reached.
a) Water shortage or no inlet pressure. Re-establish the supply of water to the booster system.
When the inlet pressure has been re-established, press
[RESET] to restart the system.
3. The booster system has
stopped and cannot
restart.
a) The pressure transmitter is defective. Replace the pressure transmitter.
0-145 psi (0-10 bar) transmitters with 0-10 V, 0-20 mA or
4-20 mA output signals are monitored by the booster
system.
b) The cable is broken or short-circuited. Repair or replace the cable.
c) The power supply to CU 323 has been
switched off. Connect the power supply.
d) CU 323 is defective. Contact Grundfos.
4. Unstable water supply
from the booster
system.
a) The inlet pressure is too low. Check the inlet pipe and the inlet strainer, if any.
b) The inlet pipe, strainer or pumps are
partly blocked by impurities. Clean the inlet pipe, strainer or pumps.
c) The pumps suck air. Check the inlet pipe for leakages.
d) The pressure transmitter is defective. Replace the transmitter.
5. The pumps are running,
but deliver no water.
a) The valves are closed. Open the valves.
b) The inlet pipe or pumps are blocked by
impurities. Clean the inlet pipe or pumps.
c) The non-return valve is blocked in the
closed position.
Clean the non-return valve. Check that the non-return valve
moves freely.
d) The inlet pipe is leaky. Check the inlet pipe for leakages.
e) There is air in the inlet pipe or pumps. Vent and prime the pumps. Check the inlet pipe for
leakages.
6. The booster system is
unable to reach the
setpoint.
a) The consumption is too high. • Reduce the consumption, if possible.
• Install a bigger booster system.
b) Too many standby pumps have been
selected. Reduce the number of standby pumps.
c) There is a pipe fracture or a leakage in
the system.
Check the system, and repair the damaged parts, if
necessary.
7. Leakage from the shaft
seal.
a) The shaft seal is defective. Replace the shaft seal.
8. Noise. a) The pumps are cavitating. Clean the inlet pipe or pumps and possibly the inlet strainer.
9. Very frequent starts and
stops.
a) The diaphragm tank precharge pressure
is not correct. Set the correct precharge pressure.

19
English (US)
15. Technical data
15.1 Pressure
Inlet pressure
We recommend that you calculate the inlet pressure in these
cases:
• Water is drawn through long pipes.
• Inlet conditions are poor.
To avoid cavitation, make sure that there is a minimum inlet
pressure on the inlet side of the booster system. The minimum
inlet pressure in psi can be calculated as follows:
NPSH can be read from the NPSH curve at the maximum
capacity at which the pump will run.
See Grundfos CM, CME Data booklet 98435269 / L-CM-PG-001.
Maximum inlet pressure
The actual inlet pressure plus the pressure when the pump is
operating against a closed valve must always be lower than the
maximum system pressure.
Operating pressure
As standard, the maximum operating pressure is 232 psi (16 bar).
15.2 Temperature
Liquid temperature: 0 to 140 °F (0 to 60 °C).
Ambient temperature: 0 to 104 °F (0 to 40 °C).
15.3 Relative humidity
Maximum 95 %.
15.4 Sound pressure level
See the installation and operating instructions for the CM pumps.
The sound pressure level for a number of pumps can be
calculated as follows:
15.5 Electrical data
Supply voltage
See the nameplate.
Digital inputs
Analog inputs
Digital outputs (relay outputs)
All digital outputs are potential-free relay contacts.
A positive inlet pressure is required before startup
and during operation.
In this document, the term "inlet pressure" is defined
as the pressure or vacuum which can be measured
immediately before the booster system.
H=P
b - NPSH - Hf- Hv- Hs
Pb=
Barometric pressure in feet (33.9 feet at sea level).
In closed systems, pbindicates system pressure in
feet.
Hf=Friction loss in suction piping in feet. (At the highest
flow the pump will be delivering.)
Hv= Vapor pressure in feet.
NPSH = Net Positive Suction Head in feet.
Hs= Safety margin = minimum 2 feet
If "H" is calculated as positive, the pump can operate
at a suction of maximum "H" feet. If "H" is calculated
as negative, an inlet pressure (psia) of minimum "H"
feet is required.
P (psi) = H/2.31
Lmax = Lpump + (n - 1) x 3
Lmax = Maximum sound pressure level
Lpump = Sound pressure level for one pump
n = Number of pumps
Considering the flow in pipes, vibrations, etc., the
actual sound pressure level of the booster system
will be lower than 90 dB(A).
Open-circuit voltage 24 VDC
Closed-circuit current 5 mA, DC
Frequency range 0-4 Hz
All digital inputs are supplied with PELV voltage
(Protective Extra-Low Voltage).
Input current and voltage
0-20 mA
4-20 mA
0-10 V
Tolerance ± 3.3 % of full scale
Repetitive accuracy ± 1 % of full scale
Input resistance, current < 250 Ω
Input resistance, voltage 10 kΩ± 10 %
Supply to sensor 24 V, maximum 50 mA per
sensor, short-circuit-protected
All digital inputs are supplied with PELV voltage
(Protective Extra-Low Voltage).
Normally open contacts
(DO1, DO2 and DO3) C, NO
Normally closed contacts
(DO4 and DO5) C, NC, NO
Optional tank fill panel auxiliary contacts
High level, (DO6) C, NO
Low Level, (DO7) C, NC
Maximum contact load 240 VAC, 2 A
Minimum contact load 5 VDC, 10 mA
Some outputs have a common C terminal. For further
information, see the wiring diagram supplied with the
booster system.

English (US)
20
Inputs for PTC sensor or thermal switch
For PTC sensors to DIN 44082. Thermal switches can also be
connected.
16. Related documents
You find further product information about the booster systems in
the following documents.
All documents are available in Grundfos Product Center:
www.grundfos.com > International website > Grundfos Product
Center.
* The instructions are only relevant for Hydro Multi-B booster
systems.
** A wiring diagram is supplied with the booster system.
16.1 Service documentation
Service documentation is available in Grundfos Product Center
under the specific product.
If you have any questions, please contact the nearest Grundfos
company or service workshop.
17. Disposing of the product
This product or parts of it must be disposed of in an
environmentally sound way:
1. Use the public or private waste collection service.
2. If this is not possible, contact the nearest Grundfos company
or service workshop.
Open-circuit voltage 8 VDC ± 15 %
Closed-circuit current 1.7 mA, DC
Inputs for PTC sensors are electrically separated
from the other inputs and outputs of the booster
system.
Title Frequency
[Hz]
Publication
number
Data booklets
Grundfos Hydro Multi-B 60 98607787
Installation and operating instructions
CM 60 L-CM-TL-001
CRE, CRIE, CRNE, CRKE,
SPKE, MTRE, CME* 60 98566351
CU 323 50/60 97775216
Diaphragm tank - 98817081
Service documentation
Service instructions 60 97921460
Service kit catalogue 50/60 96488862
Other documentation
** - -