Zenit MIXER Serie Manuel D'installation Et D'utilisation page 31

better together
5.5 Thermal protection
Models with thermal protectors are equipped with bimetal thermal switches (one for each phase, connected in series) built into the stator windings
to shut down the power supply in case of motor overheating.
Technical characteristics:
Rated voltage: 250 V
Max. switching current: 2.5 A at cos φ = 1
Nominal switching temperature (NST): 150 °C
As option, bimetallic protectors can be replaced by PTC thermistors or PT100 sensors.
The thermal protection wires are marked with a label stating "TP" = THERMAL PROTECTION.
The connection of the thermal protectors to the control panel is mandatory. The control panel must be predisposed to guarantee
the shutdown of the motor when the thermal protection intervenes and to avoid the automatic start-up of the mixer which must
only be started manually with the intervention of a technician after having fixed the causes of the anomaly.
5.6 Leakage detector
The mixer can be equipped with a single-signal dual probe that, by mean of a relay for conductive liquids, can detect the presence of water or
humidity in the oil chamber of the mechanical seals and in the motor.
The leakage detector is of single electrode type and uses the equipment grounding conductor (PE) as the return path of the detection circuit; the
circuit must be supplied by an insulating transformer.
The signal conductor is marked with a label with the letter "S".
In the case of detection (electric resistance less than 30 kΩ) take out of service the mixer and proceed with maintenance
The connection of the leakage detector to the control panel is mandatory and must be carried out by inserting in safe area an
Intrinsic Safety Barrier with galvanic isolation.
Electrical safety data for intrinsically safe circuit are:
Leakage detector
Ui: 30V; Ii: 120mA; Pi: 1.3W; Ci: 0.3nF; Li: ~ 0mH
Cable Cc: 200pF/m; Lc: 1µH/m; Lc/Rc= 30µH/Ω
S PE
DIRECT TRANSMISSION models
5.7 Electrical connection
To set up the electrical connection, do the following:
• Check on the dataplate the mixer electrical variant and the type of electrical connection (DOL or Y/D).
• First, connect the earth wire to the relative terminal in the electrical panel, according to the connection diagram.
• Connect the power wires to the relative terminals in the electrical panel, according to the connection diagram.
• Connect the wires of the control devices to the terminals on the relative panel.
All unused conductors must be insulated and properly fixed in the electrical panel.
ELECTRICAL WIRING DIAGRAMS PAGE 111
caution
For Non-standard sensors and protective devices, refer to the specific documentation supplied with the unit.
Safety, Installation and Operations Manual – Translation of original instructions
S PE
GEAR DRIVE models
EN
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