- 11 -
EBARA
Corporation
(b) Thermal protector (Built-in in 3.7kW to 22kW motor)
When temperature of the winding raises and reaches the thermal protector acting point, the motor
protection circuit is activated to protect motor from over heat.
Connect to the control panel in accordance with the following specifications.
Be sure to install a thermal relay on the control panel, since the thermal protector is not capable of
detecting sudden temperature rises caused by single phase or locked rotor.
Contact rating: AC230V, 13A (Max.)
Contact type: break contact (normal close)
Cable: 2 cores chloroprene cabtyre cable -200V
：
1.25 mm
2
/400V
：
1.00mm
2
(non-polarity)
6
Operation
Warning
During the operation of the pump, do not insert hand or foot in the suction opening of
the pump to avoid injury at the rotary section.
Never operate the pump in water in the presence of personnel.
If electric leak occurs, the personnel may suffer electric shock.
Do not execute dry operation in air. That type of operation causes deterioration in
insulation to lead to electric shock and electric leak.
1. Before starting
1) After completing the installation work, measure again the insulation resistance in accordance with
５
-1 "Confirmation before installation".
2) Confirm that the water level is satisfactory. If the pump is operated for a long period of time under dry
condition or at near the operable minimum water level, the Auto-cut in the motor is actuated. If the
situation is repeated, the pump life becomes short. Once the Auto-cut is actuated, the motor does not
start until it is cooled. (Even during the period of Auto-cut functioning, the power is supplied up to the
pump. Since the pump will restart without indication, the inspection shall be given after cut OFF the
power source.)
3) Operate the pump within the range given in the chart.
4) Frequent start-stop operations damage the pump in early stage of life. Limit the starting frequencies
as beloW
Output
The number of starting times per hour
up to 7.5kW
10
from 11 to 22kW
7
2. Test operation
1) Confirm the absence of abnormal starting by ON and OFF the
switch for once or twice in a state of slightly opened gate valve.
2) Then, confirm the rotational direction. After starting the pump,
if the discharge rate is small and if an abnormal sound is
generated, the rotational direction is reverse. In that case,
replace two-phases from each other among three of them,
(refer to Fig. 6).
3) Once the correct rotational direction is established, gradually open the gate valve, and confirm the
absence of abnormality in pressure, discharge rate, current, etc. (refer to 8 "Troubleshooting"). If
the current exceeds the rated current without using the gate valve, the design plan shall be reviewed.
3. Operation
After completing the test operation, the operation can immediately be started. Do not operate the pump
in a state of full-opening of gate valve.
Note
Operate the pump at a discharge rate suitable for the facilities.
(Operation at excessively small or large capacity causes noise and vibration, and
consumes unnecessary power.)
Fig. 5
Switch box
Switch box
Motor
Motor
U1 V1 W1
W1
V1 U1
Fig. 6
