6
NOTICE: Please turn to Starting before proceeding any further.
Operation of open systems with the liquid level below the top
of the pump:
NOTICE: The suction pipe requires a check valve or isolation
valve.
1. Close the discharge isolation valve.
2. Remove the vented priming plug.
3. Pour liquid through the priming port until the suction pipe
and the pump are completely filled with liquid.
4. Replace the vented priming plug and tighten it securely.
5. Repeat steps 1–4 until the pump is primed.
NOTICE: Please turn to Starting before proceeding any further.
CHECKING DIRECTION OF ROTATION. NOTICE: Do not
disconnect the motor from the shaft to check the direction of
rotation. If you remove the coupling, then you must adjust the
shaft position when you reinstall it. This must be done before
starting the pump.
Arrows on the pump coupling show the correct direction of
rotation. When seen from the motor fan, the pump should rotate
counterclockwise (
). For pump motors without a fan remove
one of the coupling guards and look at the coupling to determine
the direction of rotation. Turn off the pump and replace coupling
guard.
NOTICE: Do not check the direction of rotation until the pump
has been filled with liquid. See Priming.
1. Switch power off.
2. Remove the coupling guard and rotate the pump shaft to be
certain it can turn freely. Replace the coupling guard.
3. Verify that the electrical connections are in accordance with
the wiring diagram on the motor.
4. If the fan is visible, turn on and off to verify rotation.
5. To reverse the direction of rotation, first switch OFF the
power supply.
6. On three-phase motors, switch 2 of the 3 power leads on
the load side of the starter. On single-phase motors, see the
connection diagram on the motor nameplate. Change the
wiring as indicated.
7. Switch on the power supply and recheck the direction of
motor rotation.
STARTING.
1. If a suction line isolation valve has been installed, check to
be sure that it is completely opened.
2. For initial starting, the isolation valve in the discharge pipe
should be almost closed.
3. Start the pump.
4. When the piping system has been filled with liquid, slowly
open the discharge isolation valve until it is completely
open. Opening the valve too fast may result in water hammer
in the discharge pipe. If the pump or system starts to rattle,
the pump is cavitating; to avoid damage to the pump, reduce
the flow through the discharge isolation valve until the
rattling stops. If this does not give adequate flow for your
installation, call your installer or system designer.
5. Record the voltage and amperage of the motor. Adjust the
motor overloads if required.
6. If pressure gauges have been installed, check and record
operating pressures.
7. Check all controls for proper operation.
MOTOR BEARINGS. For the greasing schedule and greasing
procedure of the motor bearings, follow the motor manufacturer’s
recommendations.
CALCULATING MINIMUM INLET PRESSURE. Minimum
inlet pressure is required to avoid cavitation in the pump and is
calculated as follows:
H = Pb - NPSHR - H
f
- H
v
- H
s
H = Minimum inlet pressure in ft. of head
Pb = Barometric pressure in ft.
1 Bar = 29.53 inches of mercury (Hg)
1 PSI = 2.31 ft. of head
1 Bar = 33.5 ft. of head
NPSHR = Net Positive suction head required. To be read from
the NPSHR curve, Figure 7, at the highest flow the pump will
be delivering.
H
f
= Friction loss in suction pipe in ft. of head
H
v
= Vapor pressure in ft. of head (see Table II).
H
s
= A safety margin of 1.64 ft. of head
Example for PVM32:
If:
Flow = 145 GPM
Pb = 1 Bar = 29.53 inches of mercury*
(convert from Bar to ft. of head)
1 inch of mercury = 1.13 ft. of water
T = 100°F
NPSHR = 10' (see Figure 7)
H
f
= 10' of 2-1/2" steel pipe @ 14.5' of loss per
100' of pipe (H
f
= 14.5'/10 = 1.45')
H
v
= 2.195' (from Table II)
H
s
= 1.64' (safety factor from above)
Warning:
Hazardous Voltage
Voltage can shock, burn or cause death. Ground the pump
motor correctly before connecting to power supply per article
250-80 of National Electrical Code (NEC) in the U.S., or the
Canadian Electrical Code (CEC), as applicable.