IWAKI PUMPS MXM Series, Instruction Manual

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Operation
2. Operation
1. Fully close a discharge valve and fully open a suction valve.
2. Prime the pump.
• If the pump is in the flooded suction application, fully open both discharge and suction valves.
• If the pump is in the suction lift application, prime a suction line as well as the pump.
3. Check rotating direction of the motor.
• Close a discharge valve. Power the motor for a quick moment (within a second) in order to check the
rotation direction. A correct direction is shown with an "arrow" mark on the pump (Clockwise seen from
motor fan side).
• Check if the motor fan smoothly stops when turning off power.
NOTE: If the motor does not stop smoothly, check rotating parts.
4. Air elimination
• Before full-scale operation, eliminate the air in the pump.
• Fully open an air vent line. Run the pump for one second and repeat it 3 to 5 times for air elimination.
• After the air elimination, fully close a discharge valve.
NOTE: In case air vent line is not equipped, repeat the momentary run several times with a
discharge valve open.
5. Full-scale operation
• Start the pump with a discharge valve fully closed.
NOTE: Stop the closed-discharge operation within one minute.
• Check that discharge pressure rises to the shut off pressure.
• Gradually open discharge valve to obtain the specified pressure (capacity).
NOTE: Pay attention to the over-load caused by an excessively opened valve.
Precautions on operation
1. When the pump keeps running in negative rotation, the pump breaks.
2. Closed-discharge operation should be stopped within one minute.
3. Observe the minimum flow rate. Otherwise, friction heat may build up and damage the bearing and
sliding parts.
MXM220/221/441/442 MXM542/543/545
Impeller code Min fl ow rate Impeller code Min fl ow rate
1, 2 10L/m
1, 2, 3 20L/m
4 50L/m
*See page 6 "
2. Model codes".