Franklin 2007 ユーザーズマニュアル

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Application – Three-Phase Motors
17.  Open Atmosphere Booster Pump Systems: When 
an open booster is placed in a lake, tank, etc. that is 
open to atmospheric pressure, the water level must 
provide suffi cient head pressure to allow the pump 
to operate above its NPSHR requirement at all times 
and all seasons. Adequate inlet pressure must be 
provided prior to booster start-up.
Four Continuous Monitoring System Requirements 
for Sealed Booster Systems.
1.  Water Temperature: Feed water on each 
booster must be continuously monitored and 
not allowed to exceed the motor nameplate 
maximum ambient temperature at any time. IF 
THE INLET TEMPERATURE EXCEEDS THE 
MOTOR NAMEPLATE MAXIMUM AMBIENT 
TEMPERATURE, THE SYSTEM MUST 
SHUTDOWN IMMEDIATELY TO PREVENT 
PERMANENT MOTOR DAMAGE. If feed water 
temperatures are expected to be above the 
allowable temperature, the motor must be derated. 
See Franklin’s AIM Manual Hot Water Applications 
section for derating guidelines. (The high 
temperature feed water derating is in addition to the 
exchange to DI water derating if the motor factory fi ll 
solution was exchanged to DI water.)
2.  Inlet Pressure: The inlet pressure on each booster 
module must be continuously monitored. It must 
always be positive and higher than the NPSHR (Net 
Positive Suction Head Requirement) of the pump. 
A minimum of 20 PSIG (1.38 Bar) is required at all 
times, except for 10 seconds or less when the motor 
is starting and the system is coming up to pressure. 
Inline Booster Pump Systems (continued)
Even during these 10 seconds the pressure must 
remain positive and be higher than the NPSHR (Net 
Positive Suction Head Requirement) of the pump.
PSIG is the actual value displayed on a pressure 
gauge in the system piping. PSIG is the pressure 
above the atmospheric conditions. If at any time 
these pressure requirements are not being met, the 
motor must be de-energized immediately to prevent 
permanent damage to the motor. Once the motor is 
damaged, it is usually not immediately noticeable, 
but progresses and results in a premature motor 
failure weeks or months after the damage occurred.
Motors that will be exposed to pressure in excess 
of 500 psi (34.47 Bar) must undergo special high 
pressure testing. Consult factory for details 
and availability.
3.  Discharge Flow: The fl ow rate for each pump must 
not be allowed to drop below the motor minimum 
cooling fl ow requirement. IF THE MOTOR MINIMUM 
COOLING FLOW REQUIREMENT IS NOT BEING 
MET FOR MORE THAN 10 SECONDS, THE 
SYSTEM MUST BE SHUT DOWN IMMEDIATELY 
TO PREVENT PERMANENT MOTOR DAMAGE.
4.  Discharge Pressure: The discharge pressure 
must be monitored to ensure that a downthrust load 
toward the motor is present within 3 seconds after 
start-up and continuously during operation. 
IF THE MOTOR DISCHARGE PRESSURE IS NOT 
ADEQUATE TO MEET THIS REQUIREMENT, THE 
SYSTEM MUST BE SHUT DOWN IMMEDIATELY 
TO PREVENT PERMANENT MOTOR DAMAGE.
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