ITT Goulds Pumps 3500XD, Инструкции по установке, эксплуатации и обслуживанию

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Standpipe level is set on the level controller in the control room. Output from the controller is the input to
the level control valve (LCV) on the discharge of the Model 3500XD pump.
High and low alarms in the control room should be set at 85% and 10% respectively. Neither alarm
should be interlocked to shut down the Model 3500XD. The Model 3500XD will not start if the standpipe
level is less than 10%.
Additional recommendations for level control valve operations are:
• Low limit stop of 10% open
• In the event of the valve failing closed, a time delay of one minute in the fully closed position shall
require the 3500XD motor to stop.
The exact operating level for the standpipe must be set for each specific application to obtain opti-
mum air removal and pump performance. With stock temperatures up to 170°F, a level of 3' to 5'
above the pump centerline is typical. Above 170°F, the level must be increased to account for the
increased vapor pressure of the stock. Refer to the IOM Appendix for the order specific information
on the standpipe operating level, high and low level alarms.
If the unit is equipped with a variable speed drive, output from the level controller would control the
pump speed rather than the LCV position. Refer to the IOM Appendix for the order specific informa-
tion on the control scheme for variable speed drive systems.
For Model 3500XD units operating at 10% consistency or less, the level control system is the same
as the above.
Figure 18: Vacuum pump to sewer
5.2 Level control
3500XD Installation, Operation and Maintenance Instructions 27