2. OPERATION
IOM manual Tapflo TE series
19
The performance of the pump can be adjusted by means of a frequency inverter. The pump
operation does not depend upon the direction of rotation and can achieve full capacity in
both directions of rotation.
2.2.1.
Dry running
Although the pump is prepared for dry running it is important to have in mind that long
periods of dry run may cause damage to the wearing parts of the pump. What is more, an
empty pump should operate at low speeds
–
controlled by a frequency inverter.
2.2.2.
Dead head
The pump cannot operate with closed discharge valve. This may lead to pump malfunction
and cause injury to operators in the vicinity of the pump.
The discharge pressure can never exceed 4 bar.
2.2.3.
Optimization of the pump lifetime
➢
Continuous operation at higher frequency than 50 Hz will cause premature wear of the
components. As a general rule, we recommend to run
the pump at ±20% of the rated
frequency.
➢
When the pump is shut down while pumping a liquid containing particles, the
particulate matter contained in the liquid will be deposited and get stuck inside the
pump chamber. Therefore after finishing work the pump must be emptied of the
remaining fluid. Otherwise, when starting the pump again, the diaphragm may get
damaged and the shaft may bend leading to grub screw fracture.
➢
When reducing the motor rotation speed, control the gear-motor surface temperature
if it does not exceed the nominal working temperatures stated by the gear-motor
manufacturer.
2.3.
Pump stopping
It is advisable to stop the pump by means of motor shut down. With larger pumps or longer
delivery piping water hammering may occur. It is therefore advised to install a check valve
on the discharge to protect the pump. If a suction shutoff valve has been installed, it is
advisable to close it completely after pump is fully stopped.
The pump should be stopped by cutting of electrical power to the motor or frequency
inverter (if used
–
at 50 Hz cool down should be set to 5 seconds).
If pump stoppage exceeds 30 minutes
–
relief the pressure from the diaphragm air side
NOTE!
Never stop the pump by completely closing the discharge valve without motor shut
down.
Summary of Contents for TE Series
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