NOTICE
Risk of damage from excess voltage
Incorrect or excessive mains voltage will destroy the motor.
► Always observe the motor rating plate specifications.
► Route the mains connection in accordance with locally applicable provisions.
► Always provide a suitable mains fuse to protect the motor and supply cable in the event of a fault.
– Pfeiffer Vacuum recommends the circuit breaker type "K" with slow tripping characteristic.
NOTICE
Motor damage from overheating
Limited motor fan cooling capacity, caused by low speeds, causes the motor to overheat.
► During operation with frequency converter, observe the rotation speed range specified in the
technical data.
The vacuum pumps are equipped with three-phase motors for different voltages and frequencies. The
applicable motor type is shown on the motor rating plate.
Standard versions
● Three phase motor with PTC, without switch and mains cable
5.6.1 Connecting three phase motor with 6-pin terminal board
NOTICE
Property damage from high starting torque
The specific load behavior of the vacuum pump requires direct on-line starting at full motor power.
Engine damage occurs if a different starting circuit is used.
► Always start the motor directly.
►
Never
use a star-delta start-up circuit.
Ports U1 – L2, V1 – L1 and W1 – L3 rotate the motor shaft clockwise when looking at the motor fan.
W2
U1
L1
V2
V1
W1
U2
L3
L2
W2
U2
V2
U1
V1
W1
L1
L2
L3
Fig. 6:
Delta connection for low voltage
The 3 phases are connected in series, and their connection points connected to the mains. The voltage
per phase is equal to the mains voltage, while the mains current is √3 times the phase current. The del-
ta connection is marked with the ∆ symbol. The voltage between the incoming mains supply lines is
called mains voltage. The mains current is the current flowing in the incoming supply lines.
W2
U1
L1
V2
V1
W1
U2
L3
L2
W2
U2
V2
U1
V1
W1
L1
L2
L3
Fig. 7:
Star circuit for high voltage
Installation
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