Xylem MN 414 AC Submersible Pump Motors - Manual (Page 7)

Section 2
Installation & Operation
Installation & Operation 2−1 MN414
Overview Installation should conform to the National Electrical Code as well as local codes and practices.
All Baldor Reliance Submersible Pump Motors Include thermal devices as standard.
Normally, there are four conditions during which a submersible sewage pump may be operated in gases
or vapors.
1. When the wet well is being dewatered.
2. When the pump motor assembly is being lowered down the guide rails.
The flow from the pump is needed during the installation process to ensure that solids are cleared
from the discharge flange area to ensure proper seating.
3. When low−level cutoff controls fail.
4. When low−level sensors are positioned at the bottom of the pump assembly.
Continuous Operation Gasses Or Vapors
Be sure you have selected the correct motor for your application. The horsepower rating of the motor is
determined by the pump design, impeller size & head and flow conditions.
Operating time is a function of pit size, pump capacity, and flow conditions. Only the pump manufacturer
can ensure that the pump motor is properly applied for continuous in−gas or vapor operation. As with any
motor product, it is essential that proper consideration be given to the load characteristics to ensure the
motor will not be overloaded. Should such an overload occur, thermostats embedded in the windings will
provide a signal to deenergize the motor. However, proper consideration of the application will prevent
such an overload.
Caution: Lift using Lift Eyes only. Lifting by power cords will cause motor damage. Use spreader bar to
evenly distribute lift force. Angle of lift rope (no spreader bar) should not exceed 45 from vertical,
excessive lift angle can damage motor.
Figure 2-1
Spreader
Bar
Preferred Lift
Method
Lift Eye
Pump
Motor
45 °
Maximum
Level 1
Level 2
Below Level 1
Lift Methods
Do not lift submersible motor by the water
jacket.
Use lifting straps at front and back end
brackets as shown.
Alternate Method if Water Jacket equipped
Water Jacket
The following load conditions should be noted, refer to Figure 2-1:
1. Below Level 1 (below the pump) fluid is not pumped and no load is reflected to the motor.
2. One pump should always be sized sufficiently large to draw the well down (even under maximum flow
conditions). The maximum amount of time the motor will operate fully loaded and uncovered is the
amount of time required to draw the well down from Level 2 (top of the motor) to the bottom of the
pump.
3. Time described in 2 should not be greater than 15 minutes.
4. These notes do not make allowance for the following:
a. The heat exchanger effect of the attached pump. It is pumping a relatively cool fluid and will
remove some heat.
b. The motor does not operate fully loaded completely in gas. It is fully loaded as the motor is being
uncovered.
c. !f the well is being drawn down from the top of the motor and the maximum flow conditions exist,
the influent flow will usually provide excellent cooling of the pump motor.