5
4. Cautions for Operation
4.1 Cautions for Operation
See "Danger" (1) and (2) on p.04.
See "Warning"(8), (14), (15) and (16)
on p.04 and p.05.
See "Caution" (4), (6) and (7) on p.06.
See "Note" (3), (4), (5), (6), (7), (8), (9),
(10), and (11) on p.07.
4.2 Operation of the Thermal Protection Relay
1) If the thermal protection relay operates, switch off the main power supply immediately and
contact the manufacturer. The motor will be extremely hot and should not be touched
under any circumstances.
2) When the cause of the problem has been eliminated, check that the motor has cooled,
switch on the main power supply, and check that the pump is operating.
See "Caution" (5) on p.06.
4.3 Precautions when starting
1) Starting in cold weather
The bearing grease and cup packing may harden under cold conditions, and the pump
may be difficult to start. Use the following procedure in this case.
(1) Open the inlet to atmosphere, and switch power ON-OFF two or three times until the
pump starts. If the pump still does not start, raise the ambient temperature above 0°C.
(2) With the inlet open to atmosphere, run the pump for a few minutes to warm it.
(3) Commence normal operation once the pump has warmed.
2) Precautions regarding the intake-side pressure
Set the intake-side pressure to atmospheric pressure when starting the pump.
If the pressure is lower than atmospheric pressure, it will apply a load on the motor and
may prevent the pump from starting.
If it is necessary to maintain a vacuum, attach a shut-off valve or three-way valve between
the pump and vessel. Refer to fig.3.2 for a piping example using a shut-off valve.
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Danger
!
Caution
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Note
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Warning
!
Caution
