Wilo EMU TR 50-2 Serie Instrucciones De Instalación Y Funcionamiento página 309

6.5.2 Maintenance tasks
6.5.2.1 Checking the insulation resistance
of the motor winding
6.5.2.2 Test the resistor of the temper-
ature sensor
6.5.2.3 Check the resistance of the ex-
ternal electrode for pre-chamber
monitoring
6.5.3 Three-phase motor connection
6.5.4 Monitoring equipment connection
Installation and operating instructions Wilo-EMU TR/TRE 50-2 ... 120-1
Installation and electrical connection
Residual-current device (RCD)
Comply with the regulations of the local energy supply company! The use of a residual-
current device is recommended.
If persons come into contact with the device and conductive fluids, secure the connec-
tion with a residual-current device (RCD).
Carry out the following maintenance tasks prior to installation:
▪ Check the insulation resistance of the motor winding.
▪ Test the resistance of the temperature sensor.
▪ Test the resistance of the pencil electrode (optionally available).
If the measured values differ from the specifications:
▪ Moisture may have penetrated into the motor or the connection cable.
▪ The monitoring device may be defective.
Contact customer service in the event of a fault.
Use an insulation tester to measure the insulation resistance (measuring
voltage = 1000 V). Observe the following values:
▪ At the time of initial commissioning: Insulation resistance may not be less than 20 MΩ.
▪ For further measurements: Value must be greater than 2 MΩ.
Measure the resistor of the temperature sensors with an ohmmeter. The following
measured values must be complied with:
▪ Bimetallic strip: Measured value = 0 Ohm (passage).
▪ PTC sensor (PTC thermistor): Measured value depends on the number of sensors in-
stalled. At PTC sensor has a cold resistance of between 20 and 100 Ohm.
– With three sensors in series, the measured value is between 60 und 300 Ohm.
– With four sensors in series, the measured value is between 80 und 400 Ohm.
Measure the resistor of the electrode with an ohmmeter. The measured value must ap-
proach "infinity". For values ≤ 30 kOhm, if there is water in the oil – change the oil!
The three-phase current version is supplied with bare cable ends. Connection to the
mains is established by connecting the power supply cables in the switchgear. Refer to
the attached connection diagram for more precise details regarding the connection.
Electrical connection must always be carried out by a qualified electrician!
NOTICE! The individual wires are designated according to the connection diagram.
Do not cut the wires! There is no additional assignment between the wiring diagram
and connection diagram.
Wiring diagram of the power connections for direct activation
Mains connection
U, V, W
PE (green-yel- Earth
low)
Wiring diagram of the power connections for star-delta starting
Mains connection (start of winding)
U1, V1, W2
Mains connection (end of winding)
U2, V2, W2
PE (green-yel- Earth
low)
Refer to the enclosed connection diagram for details regarding the connection and in-
stallation of the monitoring devices. Electrical connection must always be carried out
by a qualified electrician!
NOTICE! The individual wires are designated according to the connection diagram.
Do not cut the wires! There is no additional assignment between the wiring diagram
and connection diagram.
en
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