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OPERATING MODES PAGE | 50
and analog voltage, or current signals sent to the UC-2000’s ANV/C connector then control both laser
gating and power
To generate the correct analog voltage for the UC-2000 Controller from a computer or PLC, a Digital-to-
Analog (D/A or DAC) card capable of generating 0 V (laser off) to 10 V (maximum laser power) must be
installed. To generate the proper analog current, install a D/A card that can generate 4 mA (laser off) to
20 mA (maximum power). Software able to control your analog output card is required for configu-
ration.
Continuous wave (CW)
In some applications, such as high-speed marking or cutting, the time constant of the laser and the PWM
modulation causes a series of dots that may be visible on the marking surface instead of a “clean” line.
Operating the laser in CW mode (or increasing the PWM frequency) will prevent this behavior from oc-
curring.
To operate the laser in CW mode, apply a co5 VDC signal to Pin 1, PWM Positive, and Pin 6, PWM
Negative, on either the Interface A or Interface B connector. This constant voltage source forces the
internal switching electronics to remain on, providing continuous and uninterrupted laser output power.
During CW operation, however, output power cannot be changed.
Because most applications require adjustable output power, it is preferable to increase the PWM
Command signal frequency (up to 100 kHz) in high-speed applications. Refer to the Pulse Width
Modulation (PWM) section for information regarding high-frequency operation.
Important Note: NOVANTA lasers are designed for maximum performance at a 95% duty cycle.
Increasing the maximum PWM percentage beyond 95% greatly increases the laser’s heat load
with little or no corresponding increase in laser output power.
Gated operation
In many marking and cutting applications, the laser is required to pulse, or gate, on and off in synchroni-
zation with an external control signal (typically from a computer or function generator operating in the
range from DC to 1 kHz). To pulse or gate the laser, connect a signal pro5.0 VDC pulses to the
Gate connector on the rear panel of the UC-2000.