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(+10V) and one of the digital input terminals 18, 19,
27 or 29. See parameter 300 Digital inputs.
- Thermal load calculation (ETR - Electronic
Thermal Relay), based on present load and
time. This is compared with the rated motor
current I
and rated motor frequency f
M,N
The calculations take into account the need for
lower loading at low speeds due to the motor's
internal ventilation being reduced.
ETR functions 1-4 do not begin to calculate the load
until you switch to the Setup in which they have been
selected. This means that you can use the ETR function
even when changing between two or more motors.
NOTE
The electronic thermal relay (ETR) in UL
listed VLTs provides Class 20 motor overload
protection in accordance with the NEC in
single motor applications when parameter 128
is set for "ETR TRIP" and parameter 105 Motor
current is set for rated motor current.
Description of choice:
Select No protection [0] if you do not want a warning
or trip when a motor is overloaded.
Select Thermistor warning [1] if you want a warning
when the connected thermistor becomes too warm.
Select Thermistor trip [2] if you want a trip when the
connected thermistor becomes too warm.
Select ETR WARNING if you want a warning when the
motor is overloaded according to the calculations.
You can also program the adjustable frequency drive
to give a warning signal via the digital output.
Select ETR Trip if you want a trip when the motor is
overloaded according to the calculations.
Select ETR warning 1-4 if you want a warning when
the motor is overloaded according to the calculations.
= factory setting. () = display text [] = value for use in communication via serial communication port
MG.28.A8.22 - VLT is a registered Danfoss trademark
VLT® 2800 Series
You can also program the adjustable frequency drive
to give a warning signal via one of the digital outputs.
Select ETR Trip 1-4 if you want a trip when the motor
is overloaded according to the calculations.
NOTE
.
M,N
This function cannot protect the individual
motors in the case of motors linked in parallel.
130 Start frequency
(START FREQUENCY)
Value:
0.0 - 10.0 Hz
Function:
The start frequency is active for the time set in
parameter 120 Start delay, after a start command.
The output frequency will 'jump' to the next preset
frequency. Certain motors, such as conical anchor
motors, need an extra voltage/start frequency
(boost) at start to disengage the mechanical brake.
To achieve this parameters 130 Start frequency
and 131 Initial voltage are used.
Description of choice:
Set the required start frequency. It is a precondition
that parameter 121 Start function, is set to
Start frequency/voltage clockwise [3] or Start
frequency voltage in reference direction [4] and
that in parameter 120 Start delay a time is set
and a reference signal is present.
NOTE
If parameter 123 is set higher than parameter
130, the start delay function (parameter
120 and 121) will be skipped.
131 Initial voltage
(INITIAL VOLTAGE)
Value:
0.0 - 200.0 V
Function:
Initial voltage is active for the time set in parameter
120 Start delay , after a start command. This
parameter can be used for example for lifting/dropping
applications (conical anchor motors).
0.0 Hz
0.0 V
45
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