Trust Automation, Inc. TA333 High Power Linear Servo Amplifier
10-Apr-09
Page 12 of 38
1.11 Ground Connections
Command and Signal Logic
Connections to a motion controller must be referenced to ISO ground at J2. These signals include
Enable, FAULT, DTS and the analog command inputs. For single-ended command signals, reference
the TA333 command A- and B- inputs to ISO ground on connector J2.
ISO Ground and all user interface signals on J2, J3 and J4 are isolated from drive power GND and the
External 24V GND with a minimum 1500V hipot separation.
1.12 Drive Power Supply
A pair of matching power supplies (24V to 100V) must be used to power the TA333. A high quality
switching supply is suitable for most applications. These supplies tend to be small, affordable, and
highly available. Trust Automation recommends supplies with an output ripple less than 100mV. Some
high quality supplies available offer less than 50mV. In some cases, particularly where there is great
concern for noise interference, a linear power supply, regulated or unregulated, will be required. For
unregulated supplies, verify that the voltage supplied either at V+ or at V- does not exceed the absolute
maximum supply voltage of 100V. Also note that the supplies must be within 12V of each other or a
supply fault will be generated.
When using the TA333 or any linear servo amplifier, power supply voltage that is not delivered to the
motor will be lost as heat in the amplifier.
(See section 1.14)
When selecting supplies for a given motor application it is recommended that the total voltage be
approximately 20V more than the required motor voltage. (The TA333 can drive to within ~ 8V of the
supply). Excessive supply voltages will result in higher peak wattage dissipation. Reference the SOA
graph for actual currents allowed.
(See section 2.4)
Figure 3 – Drive Power Connection
Connect the positive supply positive “+” to V+ and the positive supply negative “-” to GND. Connect the
negative supply positive “+” to GND and the negative supply negative “-” to V-. This is shown in Figure
3 above.
Note: When designing a system E-stop, never cut the motor leads. Doing so will result in a runaway
condition and may damage the TA333. Always cut the incoming DC supply (crowbar with a low value
resistor) to the TA333 to produce a rapid stop.
