CHAPTER 7 - PROGRAMMING INFORMATION AND SUGGESTIONS
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In order to make the setting easier, all the under- and over- protections
of the SSW-06 are adjusted in percentage of the motor nominal values.
These functions are normally used for the motor protection.
Initially the following data are necessary:
1) Nominal motor voltage adjusted in P400, it is a motor nameplate
data.
2) The voltage variation tolerated by the motor, it is a motor manu-
facturer catalog data, normally from -15% to +10% of the nominal
voltage.
Setting example:
Nominal motor
voltage of 380V,
Voltage tolerance from -15% to +10%.
P400=380V
P600=15%
P602=10%
Therefore, when there is a voltage drop deeper than 15% in the supply
voltage, regarding the nominal voltage, the undervoltage protection
will trip. And when there is a voltage increase higher than 10% in
the supply voltage, regarding the nominal voltage, the overvoltage
protection will trip.
It is normally used for the detection of no load pump; it can also be
used for the detection of loads under the minimum allowed value.
It can be configured according to the needs and
knowledge
of the
user among: Undercurrent, Undertorque or Underpower. All these
functions present the same form of protection; however, Undertorque
and Underpower are more sensitive and detect variations in both
voltage and current.
Example of Undercurrent setting:
Nominal motor current of 100A.
There is a normal ±10A load oscillation in this application.
Without load it drops to 60A.
In percentage:
There is a normal load oscillation of ±10% of the nominal motor
current.
There is a 40% drop in the nominal motor current for the no load
condition.
In order to get Underload detection, the Undercurrent protection must
be programmed between 10% and 40% (30% for instance):
P401=100A
P610=30%
P611=1s
Therefore, when there is a drop bigger than 30% in the motor current,
regarding the nominal current, the protection will trip.
The same sequence demonstrated above is valid also for Undertorque
and Underpower; however the respective parameters for the desired
function must be adjusted.
It can be configured according to the needs and
knowledge
of the
user among: Overcurrent, Overtorque or Overpower. All these func-
tions present the same form of protection; however, Overtorque and
7.2.2 Under- and
Over- Protections
7.2.2.1 Undervoltage and
Overvoltage protection
7.2.2.2 Underload Protection
7.2.2.3 Overload Protection
Summary of Contents for SSW06
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