Trane VarioTrane TR1 2800 Series, Operating Instructions Manual

Page: 51 / 137

420 Speed PID D- gain limit
Value:
5.0 - 50.0
5.0
Function:
It is possible to set a limit for the gain provided by the
differentiator. Since the D-gain increases at higher
frequencies, limiting the gain may be useful. This en-
ables obtaining a pure D-gain at low frequencies and
a constant D-gain at higher frequencies.
Description of choice:
Select the required gain limit.
421 Speed PID lowpass filter time
Value:
20 - 500 ms
100 ms
Function:
Noise in the feedback signal is dampened by a first
order lowpass filter to reduce the noise's impact on
the regulation. This might be an advantage, e.g. if
there is a great amount of noise on the signal. See
drawing.
Description of choice:
If a time constant (t) of 100 ms is programmed, the
cut-off frequency for the lowpass filter will be 1/0.1 =
10 RAD/sec., corresponding to (10 / 2 x
π ) = 1.6 Hz.
The PID regulator will then only regulate a feedback
signal that varies with a frequency of less than 1.6 Hz.
If the feedback signal varies by a higher frequency
than 1.6 Hz, it will be dampened by the lowpass filter.
423 U1 voltage
Value:
0.0 - 999.0 V
par. 103
Function:
Parameters 423-428 are used when in parameter 101
Torque characteristic
a selection has been made of
Special motor characteristic [8]. It is possible to deter-
mine a U/f characteristic on the basis of four definable
voltages and three frequencies. The voltage at 0 Hz is
set in parameter 133
Start voltage
.
Description of choice:
Set the output voltage (U1) that is to match the first
output frequency (F1), parameter 424
F1 frequency .
424 F1 frequency
Value:
0.0 - par. 426
F2 frequency
Par. 104 Motor fre-
quency
Function:
See parameter 423 U1 voltage .
Description of choice:
Set the output frequency (F1) that is to match the first
output voltage (U1), parameter 423
U1 voltage .
425 U2 voltage
Value:
0.0 - 999.0 V
par. 103
Function:
See parameter 423 U1 voltage .
Description of choice:
Set the output voltage (U2) that is to match the sec-
ond output frequency (F2), parameter 426
F2 frequen-
cy.
426 F2 frequency
Value:
Par. 424 F1 frequency - par. 428 F3
frequency
Par. 104
Mo-
tor frequency
Function:
See parameter 423 U1 voltage .
Description of choice:
Set the output frequency (F2) that is to match the sec-
ond output voltage (U2), parameter 425
U2 voltage .
50 TR1 2800 Series VFD
Programming