Wilo Rexa CUT, Installation And Operating Instructions Manual

Page: 57 / 384

Installation and operating instructions Wilo-Rexa CUT 57
APPENDIX English
Connection of sealing chamber control
• The pencil electrode must be connected via an
evaluation relay. We recommend the “XR-41x”
relay for this. The threshold is 30 kOhm.
• The connection must be made using an intrinsi -
cally safe electric circuit!
Operation on the frequency converter
• Continuous operation up to rated frequency
(50 Hz or 60 Hz), observing the min. flow rate
• Consider additional measures with regard to
EMC (choice of frequency converter, using
filters, etc.).
• Never exceed the rated current or rated speed
of the motor.
• It must be possible to connect the motor’s own
temperature monitor (bimetallic strip or PTC
sensor).
10.3.4. Commissioning
RISK of fatal injury due to explosion!
Pumps without Ex labelling may not be used
in potentially explosive areas! There is a risk
of fatal injury due to explosion! Observe the
following when using the pump in explosion
hazard areas:
• The pump must be approved for use in poten-
tially explosive areas!
• The power supply cable must be connected
outside the potentially explosive area, or
inside a housing with ignition protection con-
forming to DIN EN 60079-0!
• Switchgears must be installed outside the
potentially explosive area, or inside a hous-
ing with ignition protection conforming to
DIN EN 60079-0! Furthermore, these must
be configured for operation of pumps with
explosion approval.
• The mounted accessories must be approved
for use on Ex pumps.
RISK of fatal injury due to explosion!
The housing of the hydraulics must be fully
flooded (completely filled with the fluid) dur -
ing operation. If the housing is not immersed
or there is air in the hydraulics, flying sparks
may cause an explosion, for example due to
static charge! Ensure that dry-running pro-
tection is in place for switching off.
In addition to the information in the “Commis -
sioning” section, note the following points for
Ex-rated pumps:
• The operator is responsible for defining the
potentially explosive area. Only pumps with Ex
approval may be used within a potentially explo -
sive area.
• Ex-rated pumps must be identified accordingly.
• To keep dry motors sufficiently cooled in S3
mode, they must be flooded completely before
being switched back on if the motor has been
taken out of the fluid!
10.3.5. Maintenance and repair
ELECTROCUTION hazard!
There is a risk of fatal electric shocks when
performing work on electrical devices. With
all maintenance or repair work, the pump
must be disconnected from the mains and
secured against being switched on again
without permission. Damage to the power
supply cable may only be rectified by a quali -
fied electrician.
In addition to the information in the “Mainte -
nance and repair” section, note the following
points for Ex-rated pumps:
• The maintenance and repair work described in
this operating and maintenance manual must be
carried out properly.
• Repairs and alterations to the construction which
are not listed in this operating and maintenance
handbook or which may impair explosion protec -
tion may only be performed by the manufacturer
or by service dealers certified by the manufac -
turer.
• The spark-proof gaps may only be repaired
according to the manufacturer’s design speci -
fications. It is not permitted to carry out repairs
according to the values in tables 1 and 2 of DIN
EN 60079-1.
• Only the plugs stipulated by the manufacturer,
fulfilling at least a strength category of 600 N/
mm², may be used.
Cable changes
Cable changes are strictly prohibited and may
only be carried out by the manufacturer or by
service centres certified by the manufacturer.
10.4. Spare parts
Spare parts can be ordered from Wilo customer
service. To avoid return queries and incorrect or -
ders, the serial and/or article number must always
be supplied.
Subject to change without prior notice!