5.3
Operation with frequency con-
verter
5.4
Operation in an explosive atmos-
phere
Approval according to
ATEX
FM
CSA-Ex
Installation and operating instructions Wilo-EMU TR/TRE 216 ... 326-3
Product description
Monitoring the motor compartment and sealing chamber
The motor compartment monitoring protects the motor winding from short-circuits. The
sealing chamber control detects fluid ingress from the gear chamber. In each case, the hu-
midity is recorded by an electrode in the motor compartment and sealing chamber.
NOTICE! In the Ex version, this monitoring is omitted!
Motor winding monitoring
Thermal motor monitoring protects the motor winding from overheating. A temperature
limiter with a bimetallic strip is fitted as standard. Once the activation temperature has been
reached, deactivation with reactivation lock must take place.
As an option, the temperature can also be measured with a PTC sensor. Thermal motor
monitoring can also be designed as a temperature controller. This allows two temperatures
to be measured. Once the low activation temperature has been reached, an automatic reac-
tivation can be initiated after the motor has cooled down. The unit is forced to deactivate
with reactivation lock once the high activation temperature has been reached.
External monitoring of the pre-chamber
The pre-chamber can be equipped with an external pencil electrode. The electrode registers
fluid ingress through the mechanical seal on the fluid side. An alarm or deactivation of the
mixer can therefore be activated via the system controller.
Operation on the frequency converter is permitted. Refer to the appendix for the relevant
requirements!
o
o
o
o
o
o
o
o
o
−
o
−
Legend
− = not available/possible, o = optional, • = standard
For use in explosive atmospheres, the mixer must be marked as follows on the rating plate:
ƒ
"Ex" symbol for the relevant approval
ƒ
Ex classification
For the relevant requirements, refer to the explosion protection chapter in the appendix
of these installation and operating instructions!
ATEX approval
The mixers are suitable for operation in potentially explosive atmospheres:
ƒ
Device group: II
ƒ
Category: 2, zone 1 and zone 2
Mixers must not be used in zone 0!
o
o
o
o
o
o
o
o
o
−
−
o
o
o
o
o
o
o
o
o
−
o
−
o
en-US
o
o
−
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