User manual

POWER SUPPLY AND WIRING CONSIDERATIONS
1. Make sure that the applied supply voltage is adequate to drive the motor at
maximum current and maximum RPM. This should equal the maximum motor
voltage on load, plus saturation losses in the amplifier and an extra 5 to 10 percent
for ripple.
2. Under low input supply conditions, the voltage requirement of (1) may not be met,
and this may be seen effectively as poor regulation at high speeds, since the
amplifier may not have adequate ‘headroom’.
3. When operating with low voltage supplies close to 24V, check the Normal LED
while accelerating. If it goes off occasionally, it may be due to supply going below
22V while the motor draws accelerating current. In this case, filter capacitor value
and / or supply voltage should be increased.
4. When operating with higher supply voltages close to 150V, check the Normal
LED while decelerating. If it goes off occasionally, it may be due to the fact that
the energy pumped back from the inertial load back to the power supply capacitor
causes the supply to exceed 155V. In this case, reduce the power supply voltage,
reduce the deceleration rate or install a regenerative brake. Contact factory for
details of regenerative brake.
5. When connecting multiple amplifiers from the same supply, use a ‘star’
connection with supply wires to each amplifier going directly to the filter
capacitor. Don’t ‘daisy chain’ by looping power leads from one amplifier to the
next. Connect P2-3 of each amplifier individually to chassis ground, and do not
ground the – terminal of the filter capacitor.
6. Use wires of appropriate size for connecting power supply and main motor leads.
Keep connecting conductors as short as possible, and avoid bundling these wires
with any sensitive control signals, as they carry large switching currents.
LOAD INDUCTANCE
DIP switches S1 and S2 can be used to set the amplifier to compensate for a range of
load inductances. The inductance range varies with applied voltage, and this should be
taken into account if significantly lower supply voltages are used.
BANDWIDTH
The bandwidth of the amplifier is –3dB at 3 KHz and is defined for small signal
operation. The effect of bandwidth is to limit the freqeuncy of a sine wave that can be
amplified, or to limit the rise time of a step input signal. The type of load will also
have an effect on bandwidth, especially with increasing inductance. The factor V/L
will be the limiting factor, as it defines the maximum rate of change of current.