MTS Systems MPA-05-460, Руководство пользователя

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Resolution R-D Converter
SW2 is used to set the resolution of the resolver to digital converter. The amplifier is
configured from the factory for 12-bit mode.
SW2 1 2 3 4 5 6 7 8 Mode
ON OFF ON OFF ON OFF ON OFF 12-bit (default)
OFF ON OFF ON OFF ON OFF ON 14-bit
The motor speed and TAC gradients are affected by these settings.
Mode Maximum Speed
12-bit 12000 rpm
14-bit 3000 rpm
TAC Compensation
SW3 is used to alter the TAC gradient characteristics when the amplifier is used as a
velocity control. SW3 switches 1-4 are used to set the TAC gradient value that is multiplied
by the base value. The base value is expressed in volts per KRPM and is .85 volts in the
12-bit mode and 2.0 volts in the 14-bit mode. The four switches represent a binary
multiplier with switch one being the most significant bit. The switches value exists when
the switch is open (OFF) and a value of zero is not allowed.
In actual practice, the best setting for the TAC gradient is the highest possible TAC gain
for the application. Amplifier saturation is based on 10 volts of either signal or TAC. With
the TAC gradient switches set at default (SW3 1-4 = ON ON OFF OFF) saturation will
occur at 10 / (3 * .85) = 3.922 KRPM in 12-bit mode. The motors KE value and the
amplifiers bus voltage will also limit the maximum speed.
The amplifiers SIG pot controls the amount of command voltage and velocity from the
external controller. The best performance will occur when the CMD pot is turned almost
full CW and the TAC gradient is increased to reduce the desired maximum speed so that
a 10 volt command equals the maximum RPM.
As TAC gain is increased, the effects of TAC ripple are also increased. It may then be
necessary to increase the amount of filtering of the TAC signal. SW3 switches 5-6 are
provided to increase filtering. Each switch adds additional filtering.
Increased TAC gain effects the performance of the amplifier based on the amount of load
on the motor. When this occurs, it may be necessary to alter the TC network associated
with the velocity loop. This is controlled by SW1 switches 4-7.
In some applications, the amplifiers performance can be improved with the used of an
external TAC signal. SW3 switches 7-8 determine where the TAC signal is derived from.
SW3 7 8 TAC Signal
OFF ON R-D converter
ON OFF External brushless TAC
When using the external brushless TAC, the signal must come from the resolver interface
connector. The assembly must have a 14 pin instead of a 10 pin strip connector, and the
motor must have a tachometer. The TAC gradient multiplier is determined by the external
tachometers TAC gradient per thousand RPM.