28
HA0303T Rev A Feb 2014
Chapter 4
6) Connect the position aligner and the Piezo units to the power supply - see Section
3.3.2.
7) Connect the PSU to the main supply and switch ‘ON’. The version number of the
embedded software is displayed on each Piezo unit during boot up. The software
version is useful when requesting technical support.
4.5.3
Basic Operation
The general procedure involves setting the position aligner to ‘Open Loop’ and using
the KM100 mirror manual actuators to adjust the beam position until the laser beam
is within the detector quadrant sensors. Once this initial position is achieved, the
position aligner is switched to ‘Closed Loop’ and the unit controls the piezo drivers
which move the piezo mirror to focus the beam in the center of the detector.
1) Power up the system. The unit will boot up in OPEN LOOP mode.
2) Adjust the TPZ001 output voltages to mid range (e.g. 37.5 V for a 75 V piezo).
3) Using the KM100 turning mirror manual actuators, position the laser beam such
that it is directed at the centre of the detector sensor array, and the center LED on
the Target display is lit.
4) Check that the piezo controller connected to the LV OUT XDIFF connector, is
driving the X-axis piezo actuator. Turn the control knob on the piezo controller to
increase the piezo drive voltage. The laser beam should move along the X axis
with very little Y axis movement. If the beam moves in the Y-axis, or diagonally,
the piezo controller is connected to the wrong actuator.
5) To ensure correct closed loop operation, the Position Demand Sense of the
optical system must be checked. An incorrect setting will cause the system to
drive to its limit of travel when switched to closed loop.
When the X-axis piezo voltage is increased, if the Target LEDs move to the left,
Caution
During item (6) ensure the power supply unit is isolated from the mains
before connecting to the T-Cube units. Always power up the units by
connecting their power supply to the mains. DO NOT connect the T-Cube
units to a 'live' external power supply. Doing so (i.e. “hot plugging”)
carries the risk of PERMANENT damage to the unit. Similarly, to power
down the unit, disconnect the power supply from the mains before
disconnecting the T-Cube.
Note
To simplify power supply connections, the T-cube units may be fitted to a
TCH002 controller hub - see Section 3.3.4. Revision 2 piezo units can also use
the hub for communications, negating the need for external wiring. This
requires certain parameters to be set in software - see Section 5.2.4.
