Dimensions And Weights; Sound Level; Installation; Electrical Connection - Grundfos CR Serie Montage- Und Betriebsanleitung

4.9 Dimensions and weights

Dimensions: See fig. C, page 69.
Weights: See label on the packing.

4.10 Sound level

See fig. D, page 70.

5. Installation

When installing the pump, follow the procedure below in order to
avoid damaging the pump.
Step
1
2
4 x ø
L
B
1
1
L
B
2
2
3
4
5
6
10
Action
Arrows on the pump base
show the direction of flow of
liquid through the pump.
Page 69 shows:
• port-to-port lengths,
• dimensions of the base,
• pipework connections and
• diameter and position of
foundation bolts.
The pump can be installed
vertically or horizontally. En-
sure that an adequate supply
of cool air reaches the motor
cooling fan. However, the mo-
tor must never fall below the
horizontal plane.
To minimize possible noise
from the pump, it is advisable
to fit expansion joints either
side of the pump and anti-vi-
bration mountings between
foundation and pump.
Isolating valves should be fit-
ted either side of the pump to
avoid draining the system if
the pump needs to be
cleaned, repaired or replaced.
The pump must always be
protected against backflow by
means of a non-return valve
(foot valve).
Install the pipes so that air
locks are avoided, especially
on the suction side of the
pump.
In the case of installations in
which:
• the discharge pipe slopes
downwards away from the
pump,
• there is a risk of siphon
effect,
• protection against backflow
of unclean liquids is neces-
sary,
a vacuum valve must be fitted
close to the pump.

6. Electrical connection

The electrical connection should be carried out by an authorized
electrician in accordance with local regulations.
Before removing the terminal box cover and before
any removal/dismantling of the pump, make sure that
the electricity supply has been switched off.
The pump must be connected to an external mains
switch with a minimum contact gap of 3 mm in all
poles.
The operating voltage and frequency are marked on the motor
nameplate. Make sure that the motor is suitable for the electricity
supply on which it will be used.
Single-phase Grundfos motors incorporate a thermal switch and
require no additional motor protection.
Three-phase motors must be connected to a motor starter.
The terminal box can be turned to four positions, in 90° steps:
1. If necessary, remove the coupling guards. Do not remove the
coupling.
2. Remove the bolts securing the motor to the pump.
3. Turn the motor to the required position.
4. Replace and tighten the bolts.
5. Replace the coupling guards.
The electrical connection should be carried out as shown in the
diagram inside the terminal box cover.

6.1 Frequency converter operation

Motors supplied by Grundfos:
All three-phase motors supplied by Grundfos can be connected to
a frequency converter.
Dependent on the frequency converter type, this may cause in-
creased acoustic noise from the motor. Furthermore, it may
cause the motor to be exposed to detrimental voltage peaks.
Note: Grundfos motors types MG 71 and MG 80 as well as
MG 90 (1.5 kW, 2-pole), all for supply voltages up to and including
440 V (see motor nameplate), must be protected against voltage
peaks higher than 650 V (peak value) between the supply termi-
nals.
It is recommended to protect all other motors against voltage
peaks higher than 850 V.
The above disturbances, i.e. both increased acoustic noise and
detrimental voltage peaks, can be eliminated by fitting an LC filter
between the frequency converter and the motor.
For further information, please contact the frequency converter or
motor supplier.
Other motor makes than those supplied by Grundfos:
Please contact Grundfos or the motor manufacturer.