ITT Goulds Pumps HSU, Инструкции по установке, эксплуатации и обслуживанию

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run of 15 minutes after the motor is no longer completely submerged if the sump is large enough to not
have completed the pump-down in that time.
The motor is rated for full horsepower with liquid temperatures of 40° C (104° F) or lower.
7.8 Pump installation
Make sure the lifting device is securely fastened to the motor lugs or hooks so the unit will not be drop-
ped when it is lowered into the sump. Check the 1/8" vent hole in the adapter plate, between the motor
and the casing, to make certain it is not plugged and then carefully lower the unit into position in the
sump. Check the pump for being approximately level. Support the discharge pipe to prevent excessive
loads from being transmitted to the pump flange and casing.
7.9 Starting the pump
The most important concern is the prevention of motor overloading. Refer to the motor nameplate for the
full load ampere rating of the motor. Install an ammeter on the motor leads and check the motor draw
immediately after the unit is started.
An excessive current draw with a 3-phase motor is an indication of wrong rotation.
Observe the discharge for flow rate, then change two of the three motor leads to reverse the direction of
rotation. If the rotation was wrong, the current draw will be reduced at the same or greater flow rate. Sin-
gle phase motors are internally wired for the correct rotation.
The ammeter on the motor leads should be checked for overload at all sump level heights with the liquid
that will be normally pumped to check for motor overload at some other condition from that encountered
at start-up. The horsepower will tend to increase as the level in the sump rises.
7.10 Locating trouble
Insufficient or no discharge can be caused by any of the following conditions:
1. Speed too low (usually due to low voltage)
2. System head too high
3. Insufficient NPSH or submergence
4. Wear of the pump parts
5. Wrong direction of rotation
6. Pump not completely primed (plugged vent hole)
7. Suction opening or discharge pipe clogged
8. Viscosity of slurry too high
7.11 Excessive current draw
Excessive current draw may be caused by any of the following conditions:
1. Wrong direction of rotation
2. Pump operating at a high horsepower area of the pump curve (capacity is greater than the de-
sign capacity)
3. Impeller rubbing or mechanical defect in the motor
4. Specific gravity or viscosity too high.
5. Low voltage
7.8 Pump installation
HSU Installation, Operation and Maintenance Instructions 13