7.8.4.3 Sweep signal
Use P 1510 - SCD_TSIG_SignalType = Sweep (2) to generate a sine signal of
variable frequency.
Define the lower frequency with P 1506 -SCD_TSIG_Freq and the upper frequency
with
P 1513 - SCD_TSIG_Freq2.
Executing a test signal from the lower to the upper frequency
Set P 1504[0] - SCD_TSIG_Time equal to the desired signal duration and P 1504[1]
- SCD_TSIG_Time = 0. One pass from the lower frequency to the upper frequency is
carried out.
Executing a test signal from the lower to the upper frequency and back
Alternatively you can set P 1504[1] - SCD_TSIG_Time = P 1504[0] - SCD_TSIG_
Time. A pass is then made from the lower frequency to the upper frequency and
back again to the lower frequency.
For repeating the test signal, use P 1502 - SCD_TSIG_Cycles.
Use P 1510 - SCD_TSIG_SignalType = TriSweep (3) to generate a triangle signal
with the same frequency behaviour.
MOOG
ID No.: CB40859-001 Date: 11/2020
MSD Servo Drive - Device Help
165
7 Control
7.9 V/Hz mode
A simple function test can be carried out in V/Hz mode. This test will show users
whether a motor is connected correctly and whether the right direction of movement
will be followed. If ...
l
The direction of movement is the wrong one
l
The motor is at a standstill,
l
Uncontrollable motion occurs,
then the connection and the motor data need to be checked.
For testing purposes, a V/Hz control system is implemented in such a way that the
closed-loop speed control circuit will be replaced by the V/Hz control. The reference
is the speed reference; the actual speed is set equal to the reference. A linear
characteristic with two interpolation points is implemented, with a fixed boost voltage
setting P 313[0] - CON_VFC_VBoost at 0 Hertz. Starting from the rated frequency
P 314[0] - CON_VFC_FNom, the output voltage will remain constant at P 315[0] -
CON_VFC_VNom. This means that an asynchronous motor will automatically be
driven to field weakening as the frequency rises.
Image 7.45: “V/Hz mode” screen
ID
Index Name
Unit Description
313
0
CON_VFC_VBoost
V
V/Hz characteristic: Boost voltage
314
0
CON_VFC_FNom
Hz
V/Hz characteristic: Nominal frequency
315
0
CON_VFC_VNom
V
V/Hz characteristic: Nominal voltage
Table 7.39: “V/Hz mode” parameters
