4.2
Monitoring devices
Internal monitoring devices
Motor compartment/sealing chamber*
Motor winding**
External monitoring devices
Pre-chamber
4.3
Operating modes
Installation and operating instructions Wilo-EMU TR/TRE 50-2 ... 120-1
Product description
Pre-chamber
The high-volume pre-chamber has been filled with gear oil to absorb any leakage at the
seal on the fluid side. A mechanical seal made of solid silicon carbide is used as the seal
on the fluid side. The mechanical seal also features a packing sleeve. The packing sleeve
ensures a permanently corrosion-resistant fit for the mechanical seal. A rotary shaft
seal made of FPM (FKM) seals towards the gear chamber. The pre-chamber can option-
ally be monitored using a pencil electrode.
Gear chamber
The gear chamber has been filled with gear oil to guarantee continuous lubrication of
the planetary gear and the gear bearings. A solid silicon carbide mechanical seal seals
towards the sealing chamber.
Sealing chamber
The high-volume sealing chamber is filled with white oil and absorbs any leakage from
the gear chamber. A rotary shaft seal made of FPM (FKM) seals towards the motor.
Overview of possible monitoring devices:
o
o
•
•
o
o
Legend
− = not available/possible, o = optional, • = standard
* In the Ex version, this monitoring is omitted and not substituted!
** A temperature limiter is fitted as standard. The Ex version as per ATEX also features
an installed temperature controller and limiter.
All the monitoring devices fitted must always be connected!
Monitoring the motor compartment and sealing chamber
The motor compartment monitoring protects the motor winding from short-circuits.
Sealing chamber control detects fluid ingress from the gear chamber. In each case, the
humidity is recorded by an electrode in the motor compartment and sealing chamber.
NOTICE! The Ex version does not feature this monitoring unit!
Monitoring of motor winding
The thermal motor monitoring protects the motor winding from overheating. Temper-
ature limiting with bimetallic strip is fitted as standard.
As an option, the temperature can also be measured with a PTC sensor. The thermal
motor monitoring can also be designed as temperature control. This allows the meas-
urement of two temperatures. When the low temperature is reached, an automatic re-
activation can be initiated after cooling the motor. When the high temperature is
reached, the unit must deactivate with reactivation lock.
External monitoring of the pre-chamber
The pre-chamber can be equipped with an external pencil electrode. The electrode re-
gisters fluid ingress through the mechanical seal on the fluid side. An alarm or deactiva-
tion of the mixer can therefore occur via the system controller.
o
−
o
•
•
•
o
o
o
en
−
•
o
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