Electrical Connection; Installing The Product; Mechanical Installation - Grundfos MS1 Montage- Und Betriebsanleitung

1.3 Notes
The symbols and notes below may appear in
Grundfos installation and operating instructions,
safety instructions and service instructions.
Observe these instructions for
explosion-proof products.
A blue or grey circle with a white graphical
symbol indicates that an action must be
taken.
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.
If these instructions are not observed, it
may result in malfunction or damage to the
equipment.
Tips and advice that make the work easier.

2. Installing the product

2.1 Mechanical installation

The float switch is freely suspended from a highly
flexible, heavy-duty cable and set at the required
level "On, Off or Alarm". The position of the float
switch changes with the rise and fall of the water
level. A micro switch opens and closes the circuit,
switching a pump on or off or triggering an alarm.
One float switch is required respectively for each
switching impulse. It is very important to ensure that
the float switch can hang freely, does not lie on the
ground, can operate without interference by shaft
walls, pipes or fittings etc. and is not directly in the
liquid flow. The power cable of the float switch must
be carefully laid along its entire length to prevent any
risk of mechanical damage. Also ensure that
moisture cannot penetrate cable ends. See fig. 1.
Valid for MS1 Ex only
To avoid the risk of the buildup of an
electrostatic charge, the casing of the float
switch must be connected to the
equipment's potential equalisation system
using the potential equalisation conductor
in the connection cable.
6

2.2 Electrical connection

DANGER
Electric shock
Death or serious personal injury
- Switch off the power supply before
starting any work on the product. Make
sure that the power supply cannot be
accidentally switched on.
- Never work on live wires.
- The float switch must be earthed.
- Ensure that neither water nor moisture
can enter via the cable ends.
Observe these instructions for
explosion-proof products.
The electrical connection must be carried
out by an authorised electrician in
accordance with local regulations.
For installation in EX-Zones 0 and 1, the
use of an intrinsically safe electrical circuit
relay is mandatory.
Connection of the Grey
float switch (1)
To empty
fig.
See 2
Alarm at
in Isolate
high liquid
appendix
level
To fill
fig.
See 3
Alarm at
in X
low liquid
appendix
level
Yellow/
Black Brown green
(2) (3) (MS1 Ex
only)
X X To ground
Isolate X To ground