English (GB)
3
4. Technical data
Minimum flow rate
The pump
must never
run without flow. The curve below shows
the minimum flow rate as a percentage of the rated flow rate in
relation to the liquid temperature.
Fig. 2
Minimum flow rate
5. Type key
See also the installation and operating instructions of CR, CRI,
CRN.
6. Mechanical installation
Before installation, check that the pump and its components are
as ordered and that no visible parts have been damaged.
6.1 Installation of pump
The pump must be installed and put into operation as described
in the installation and operating instructions of CR, CRI, CRN.
We recommend to protect CRN MAGdrive pumps against dry
running by installing a flow switch, pressure switch or a LiqTec
sensor close to the pump. The delay of the dry-running protection
must be maximum 15 seconds.
6.2 Connection of sensor
A pressure sensor or a Grundfos LiqTec dry-running protection
unit can be fitted in the threaded hole in the pump head.
7. Electrical connection
The pump must be installed as described in the installation and
operating instructions of CR, CRI, CRN.
Pumps with 2-pole motors of 18.5 and 22 kW and 4-pole motors
as from 1.1 kW must be started via a soft starter.
7.1 Motor protection
As a minimum, the motor must be connected to an effective
electronic motor protection with instantaneous release when the
maximum setting of the current is reached. If a soft starter or a
frequency converter is used it must also be with instantaneous
release.
In order to ensure the optimum protection of the MAGdrive motor,
the motor protection should be set in accordance with the
following guidelines:
1. Set the overload protection to the rated full-load current (I
1/1
)
of the motor.
2. Start the pump and let it run for half an hour at the required
duty point.
3. Measure the motor current. If not possible, slowly grade down
the scale indicator until the motor trip point is reached.
4. The setting of the motor protection must be 5 % higher than
this value.
The highest permissible setting of the motor protection is the
rated full load current (I
1/1
) of the motor.
Liquid temperature:
-30 to 120 °C.
Maximum system pressure:
25 bar.
Viscosity:
0.15 to 300 cSt (mm
2
/s).
TM
02
82
90
49
03
Example
CRN
5
-13
-M
-F -G -E
Type range
Rated flow rate in m
3
/h
Number of impellers
Code for pump version
M: CRN pump with magnetic drive
Code for pipe connection
CA: FlexiClamp
CX: TriClamp
F:
DIN flange
G: ANSI flange
J:
JIS flange
P:
PJE coupling
Code for materials
G: Wetted parts EN 1.4401/AISI 316
Code for rubber parts of pump
E: EPDM
F: FXM (Fluoraz
®
)
K: FFKM (Kalrez
®
)
N: CR (Neoprene)
V: FKM (Viton
®
)
40
50
60
70
80
90 100 110 120 t [°C]
0
10
20
30
Qmin
[%]
Warning
Installation and operation must comply with local
regulations and accepted codes of good practice.
Description
Dimension
Threaded connection:
RG 1/2
Max. installation length, sensor:
20 mm
