Motor Protection - Oase SPA 22-23 Montage- Und Betriebsanleitung

normally permitted by the Electricity Board. In the case a decreation of the start-up current
being required, a star-delta switch can be used. If frequency transformers should be used, it is
absolutely necessary to confer with the manufacturer and to get the release confirmed.
4.0.1. Direction of rotation of the motor
Before initial operation of the pump it is necessary to check the direction of rotation. The pump
must be completely submerged in the liquid to be pumped and might not suck air. The throttle
slide should be 2/3 open and the pressure pipe and the fountain nozzle should be connected.
Before initial operation the impacts of a sudden water flow have to be checked. If no
unpleasant surprises are to be expected, the pump can be switched on for a short time.
Observe and notice lifting flow and pressure resp. lifting height resp. fountain height. This test
might only be executed for a short time and repeated for max. 2-3 times.
Attention! The pump must not run dry! Not even for a short time!
Next, the two phases of the power supply have to be exchanged and the a.m. test has to be
repeated. The phase position is correct when the biggest volume flow resp. the biggest
fountain height is obtained. The correct phase position should be kept and any further changes
should be made.
4.0.2.

Motor protection

Pumps with threephase motors have to be generally connected to a motor protection switch
with differential release. During cold start, the excess-current release integrated in the motor
protection switch has to disengage in less than 10 sec., if a motor nominal current is used that
is 5 times higher. If the switch characteristics of the motor protection switch do not comply to
these requirements, the warranty for the motor is invalid. For providing the submersible motor
the best possible protection the adjustment of the motor protection switch should be made
according to the following rules:
a. Adjust overload release to nominal current of the motor.
b. Operate pump for half an hour at standard capacity.
c. Adjust overload release step by step to a lower position until release
position is reached.
d. After that, adjust overload release 5% over this release position.
OASE GmbH * Postfach 2069 * 48469 Hörstel * Tel.: 05454 / 80-0 * Fax: 05454 / 80 322
DOCUMENTATION
SPA 22 - SPA 280
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