If the user wishes to signal amplifier failures individually to the main computer, it is recommended that the uncommitted user inputs
) are used for this purpose.
If the installer of the CMM makes the decision that the amplifier enabling function is not needed, the ‘Enable amps ﴾active low﴿' signal could
be connected directly to the ‘amps OK' input signal. This will provide immediate feedback to the controller during the amplifier enabling
process and permit the next stage to begin.
NOTE:
This method is not recommended.
Contactor energising
After establishing that the amplifiers are working correctly, the controller will take the “contactor” signal ﴾pin 2 of the servo power amplifier
connector) low, this should be used to signal the servo power amplifier to apply power to the motors. The controller will keep this output
signal low for 0.2 of a second during which it expects the ‘contactor feedback' input ﴾machine I/O connector pin 24﴿ to be pulled low to
indicate that the motors are now powered.
If the ‘contactor feedback' signal is not received in time, the contactor ﴾pin 2 ﴿ and the amp control signals ﴾pins 4+5﴿ are turned off and the
motor engagement process is stopped.
If the ‘contactor feedback' signal is received within this 0.2 second window, the controller keeps all motor commands at zero for another 1.0
second before allowing the servo system to begin operating. This is intended to give further protection against sudden machine movements
when engaging the motors
If the installer of the CMM makes the decision that the contactor energising function is not needed, the ‘contactor' signal ﴾pin 2﴿ can be joined
to the ‘contactor feedback' input signal ﴾pin 22﴿. This will provide immediate feedback to the controller during the contactor energising
process and permit the next stage to begin.
NOTE:
This method is not recommended.
Motor command signals
The UCC2 controller generates complementary motor velocity command signals for each axis (X axis = pins 8+9, Y axis = pins 10+11, Z axis =
pins 12+13, 4th axis = pins 14+15).
Each motor velocity signal is capable of a swing of +/‐10 V centred on a zero velocity command of 0 V. A motor “command common”
connection is provided to define this 0 V level (servo power amplifier connector, pin 16, figure 1).
The motor command common signal is also connected to the 24 V supply return, the controller chassis and the mains supply protective
ground at a star point within the controller. Care may be required in its application.
If complementary signals are not required, either of the motor command signals may be used as a single ended input, referred to the motor
“command common” line.
Each motor command signal has a series resistor of 1k ohm to protect the controller from inadvertent damage and this will reduce the drive
signal to the power amplifiers if their inputs are of low impedance. The UCCassist-2 will compensate for this automatically.
UCC2 and UCC2-2 installation guide
www.renishaw.com
Issued 07 2021
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