Check The Direction Of Pump Rotation; Figure 12 Example Control Circuit - Edwards EH500T4 T3 Series Instruction Manual

7. Connect the thermistor wires to the control circuit.

Figure 12 Example control circuit

1. Electrical supply isolator 1. Electrical supply isolator
3. Thermistor relay 3. Thermistor relay
5. Start switch 5. Start switch
7. Pump contactor 7. Pump contactor
9. Pump motor 9. Pump motor
11. Circuit breaker 11. Circuit breaker

4.7 Check the direction of pump rotation

WARNING: ROTATING PARTS
Risk of injury and damage to equipment. Blank the inlet or connect the pump to the
vacuum system before checking the direction of pump rotation. If not, there is a
danger of objects being trapped in the rotating rotors.
It is possible for the three-phase electrical supply to the motor to be phased incorrectly.
If the supply is phased incorrectly, the rotors will rotate in the reverse direction or
remain stationary. Check the direction of rotation as described below.
1. Check that the pump is connected to the vacuum system or that the inlet is
blanked off.
2. Connect the backing pump and switch the backing pump on.
3. On all EH2600 and EH4200 model pumps, the correct direction of rotation is
indicated by an arrow on the motor fan cover
EH4200 pump
fan inside the fan cover, switch on the pump for two or three seconds, then switch
the pump off.
On all EH250FX, EH500FX and EH1200 model pumps, use the method above to
determine the direction of rotation. Alternatively, the direction of rotation is also
A30151880_AA
A30151880_AA - Installation
variants). To determine the direction of rotation: watch the motor
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2. positive control side 2. positive control side
4. Stop switch 4. Stop switch
6. Fault indicator lamp 6. Fault indicator lamp
8. 0 V control side 8. 0 V control side
10. Contactor 10. Contactor
(Figure: EH1200FX, EH2600 and
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