Operation In An Explosive Atmosphere; Operating Modes - Wilo Rexa CUT Serie Einbau- Und Betriebsanleitung

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3.2.2. Motor
In the AC or three-phase current version, glanded
motors are used as the motors. The motor is
cooled by the fluid around it. The waste heat is
transferred directly to the fluid via the motor
housing. The motor may emerge during opera-
tion.
NOTE
When the motor is non-immersed, observe and
comply with the specifications for "Non-im-
mersed operating mode".
On the single-phase AC motors in the "S" motor
version, the operating capacitor is integrated into
the motor and the starting capacitor is installed
in a separate housing. On the single-phase AC
motors in the "P" motor version, the operating
and starting capacitors are installed in a separate
housing.
The connection cable has a length of 10 m and is
available in the following versions:
• Single-phase version: Cable with shockproof plug
• Three-phase version: bare cable end
In the "P" motor version, the connection cable has
a longitudinally watertight seal.
3.2.3. Monitoring equipment
• Motor compartment monitor ("P" motor version
only):
The motor compartment monitor signals water
ingress into the motor compartment.
• Thermal motor monitor:
The thermal motor monitor protects the motor
winding from overheating. On Ac motors, this is
integrated and self-switching. This means that
the motor is switched off if it overheats and is
automatically switched on again when it has
cooled down. Bimetallic strips are used for this as
standard.
• The motor can also be fitted with an external
pencil electrode to monitor the sealing cham-
ber. This signals if there is water ingress into the
sealing chamber through the mechanical seal on
the fluid side.
3.2.4. Seal
The seal for the fluid and the motor compartment
is made via two mechanical shaft seals. The seal-
ing chamber between the mechanical shaft seals
is filled with ecologically safe medicinal white oil.
3.2.5. Materials
• Motor housing:
• Motor version "S": 1.4301
• Motor version "P": EN-GJL-250
• Hydraulic housing: EN-GJL 250
• Impeller: EN-GJL 250
• Macerator:
• CUT GI: 1.4528
• CUT GE: Abrasit/1.4034
• Shaft end: 1.4021
• Static gaskets: NBR
• Seal
40
• On pump side: SiC/SiC
• On motor side: C/MgSiO4
3.2.6. Attached plug
A shockproof plug is fitted on single-phase
motors and a CEE plug on three-phase motors.
These plugs are designed for use in commercially
available sockets and are not overflow-proof.
BEWARE of moisture!
Ingress of moisture will result in damage to
the plug. Never immerse the plug in fluid and
always protect it from moisture.

3.3. Operation in an explosive atmosphere

Pumps marked as explosion-protected are suita-
ble for operation in an explosive atmosphere. The
pumps must meet certain guidelines for this type
of use. Certain rules of conduct and guidelines
must be also followed by the operator.
Pumps that have been approved for use in an
explosive atmosphere must be marked as follows
on the rating plate:
• "Ex" symbol
• Information on Ex classification
For use in an explosive atmosphere, observe the
further specifications in the appendix to this
manual
INCORRECT use can result in danger!
When used in an explosive atmosphere, the
pump must have a corresponding approval.
Also, the accessories must be approved for
this application. Check the pump as well as
all accessories before use to verify that they
conform to this directive.

3.4. Operating modes

3.4.1. Operating mode S1 (continuous duty)
The pump can operate continuously at the rated
load without exceeding the permissible temper-
ature.
3.4.2. Operating mode S2 (short-time duty)
The maximum operating period is specified in
minutes, e.g. S2-15. The pause must last until the
machine temperature no longer differs from the
temperature of the coolant by more than 2 K.
3.4.3. Operating mode S3 (intermittent operation)
This operating mode defines a combination of
periods of operation and standstill. In S3 opera-
tion, the values given are always calculated based
on a period of 10 minutes. For example: S3 20 %
Operating time 20 % of 10 min = 2 min / stand-
still time 80 % of 10 min = 8 min
PRODUCT DESCRIPTION
WILO SE 11-2014 V05 DIN A4