Stoelting 51447 Installation, Basic Operation, Piezo Mode, Adjustment of the Piezo Drive

CONTROL UNIT PM10

Installation

The piezo translator of the unit PM10 has to be mounted with the enclosed holder to the motor driven micromanipulator DC3/DC3-K. Further the control unit must be connected to the manipulator and the piezotranslator with the two attached cables. The system is set to the supply voltage ∼115 or ∼230 volt, 50/60 Hz, as specified on the rear panel. Before plugging in, check settings.

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Read all the operating instructions in

particular the safety instructions at the end of the operating instructions before installing the system.

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Basic Operation

The forward and backward movements of the three axes of the micromanipulator DC3/DC3-K are controlled by 6 keys. If a key is pressed for less than 0.3 seconds, only one step of the micromanipulator results. Stay pressing for longer than 0.3 seconds a continuous movement succeeds to the step as long as the key is pressed. During the motor is running no further step can be initiated. The first of the 6 keys, labelled 'PIEZO', activates the piezo function in addition to the motor forward movement when used in the step mode. The step length can be set by 'STEP SIZE' from

0.5to 10 µm, the continuous velocity by 'CONTINUOUS SPEED' from 0 to 150µm/s (reduction gear 900:1) and the step velocity of the piezo forward movement 'PIEZO SPEED' from 1 to 100 mm/s. The settings of step length - 'STEP SIZE'- and of the velocity of continuous movement - 'CONTINUOUS SPEED'- are the same for all three axes. The velocity of the step movement (motor) cannot be modified externally. It is not possible to drive in more than one direc- tion at any one time.

Piezo Mode

Pressing the key for X-forward direction briefly activates the piezo mode: The piezo translator moves forward very rapidly with the selected 'PIEZO SPEED' and 'STEP SIZE'. Immediately after this step the piezo drive returns slowly at constant speed to the starting position. Simultaneously the DC motor for this axis moves forward, completely and accurately compensating the movement of the piezo drive. These piezo steps can be repeated as often as needed providing they are within the range of the motor drive.

Adjustment of the Piezo Drive

The backward movement of the piezo drive and the forward movement of the motor drive are coordinated with the grey pin on the backside of the unit. The compensation may change in time for several reasons: Ageing of components, replacement of the manipulator or piezo translator or even different positions of the manipulator. For readjustment use the potentiometer on the rear (grey pin): Select a step size of 10 µm and note the position of the micrometry screw. Push the forward key 'PIEZO' several times and compare the step size with the scale on the micrometry screw (1 mark = 10 µm). Adjust the potentiometer until one step equals one mark.

High Voltage Output

Pushing the 'PIEZO' key the output 'HIGH VOLTAGE' delivers a sawtooth pulse of up to 1000 volts, otherwise this output is non alive. To prevent risk of electric shock and damage to the unit it must only be operated with the piezo drive connected. Under no circumstances should any other devices be connected to this high voltage output or the internal pin of the outlet 'HIGH VOLTAGE' be touched.

Backlash Compensation

This control unit has built-in electronics, to compensate the backlash of the gears. If the direction is changed, the motor receives an extra current pulse, which corresponds to the backlash. This is very valuable in the step mode, as it avoids 'missing steps' (motor turns, but no movement of the micro manipulator). On the bottom of the case there is one adjusting screw for all three axes 'BACKLASH COMPENSATION'. Thus the backlash compensation can be adapted to the manipulator individually.

Remote Control

There is a small 7- pin jack on the backside of the case to connect a remote control. The remote control is an optional accessory and must be ordered separately.