Wilo Rexa CUT, Installation And Operating Instructions Manual

Page: 47 / 384

Installation and operating instructions Wilo-Rexa CUT 47
COMMISSIONING English
active and does not need to be connected sepa-
rately.
Temperature monitoring of the three-phase AC
motor
The pump is equipped with a temperature limit as
standard (1-circuit temperature monitoring). Bi -
metallic strips must be connected in the switch-
gear itself or via an evaluation relay. When the
threshold is reached, the pump must switch off.
Connection values: max. 250 V(AC), 2.5 A, cos φ
= 1
For this reason, no warranty claims can be accept
-
ed for any damage to the winding resulting from
unsuitable motor monitoring!
Motor compartment (motor version "P" only)
The motor compartment monitor must be con -
nected via an evaluation relay. We recommend
the “NIV 101/A” relay for this. The threshold is
30 kOhm. When the threshold is reached, the
pump must switch off.
Connecting the pencil electrode (available as an
option) for sealing chamber control
The pencil electrode must be connected via an
evaluation relay. We recommend the “NIV 101/A”
relay for this. The threshold is 30 kOhm. When the
threshold is reached, a warning must be given or
the unit switched off.
CAUTION!
If there is only a warning, the pump could be
irreparably damaged by water ingress. We
always recommend switching the pump off!
5.6. Motor protection and activation types
5.6.1. Motor protection
The minimum requirement for motors with a free
cable end is a thermal relay/motor protection
switch with temperature compensation, differ -
ential triggering and an anti-reactivation device
in accordance with VDE 0660 or the appropriate
national regulations.
If the pump is connected to electrical systems
in which faults frequently occur, we recommend
installing additional protective devices provided
by the customer (overvoltage, undervoltage or
phase failure relays, lightning protection etc.).
We also recommend installing a residual-current
device (RCD).
Local and national regulations must be observed
when connecting the pump.
5.6.2. Activation types
Direct activation
At full load, the motor protection should be set
to the rated current shown on the rating plate. At
partial load, we recommend that the motor pro -
tection be set 5 % above the current measured at
the duty point.
Soft start activation
• At full load, the motor protection should be set
to the rated current at the duty point. At partial
load, we recommend that the motor protection
be set 5 % above the current measured at the
duty point.
• The current consumption must be below the rat -
ed current throughout the entire operation.
• Due to the upstream motor protection, starting or
stopping should be completed within 30 seconds.
• To avoid power dissipation during operation,
bypass the electronic starter (soft start) once
normal operation is reached.
5.6.3. Operation with frequency converters
Operation with a frequency converter is only pos-
sible with motor version "P". Note the information
about this in the appendix.
Motor version "S" motors may not be operated
with frequency converters.
6. Commissioning
The “Commissioning” section contains all the im -
portant instructions for the operating personnel
for starting up and operating the pump.
The following conditions must be adhered to and
monitored:
• Type of installation
• Operating mode
• Minimum water submersion/max. immersion
depth
These general conditions must also be checked
after a lengthy period without operation, and
any defects detected must be repaired!
Always keep this manual either by the pump
or in a place specially reserved for it, where it is
accessible for the entire operating personnel at
all times.
In order to prevent damage or serious injury when
commissioning the pump, the following points
must be observed:
• Commissioning of the pump may only be carried
out by qualified and trained personnel in accord -
ance with the safety instructions.
• All persons working on or with the pump must
have received, read and understood this operating
and maintenance manual.
• All safety devices and emergency cut-outs must
be connected and checked to ensure that they
work properly.
• Electrical engineering and mechanical adjust-
ments must be made by qualified personnel.
• The pump is suitable for use under the specified
operating conditions.
• The work area of the pump is not a recreational
area and is to be kept free of people! No persons
are allowed in the work area during start-up or
operation.