Novanta v40 User Manual page 59

INPUT/OUTPUT SIGNALS
Input signals
A total of four user inputs allow control of v40 lasers. Remote Interlock, Shutter Open Request, and
Remote Reset/Start Request inputs are optoisolated and bi-directional, allowing for positive or negative
polarity signal inputs. These three signals also share a common return connection, Input Common, which
is separate from chassis ground to completely isolate control signals for optimal EMI performance. The
fourth input, PWM Input, is optoisolated and has a separate return, PWM Return, to fully isolate PWM
signals from the other three user inputs. Note that throughout this manual, input voltage levels are speci-
fied with respect to their corresponding return line.
Pin 1 PWM Return
Connect the return side of your PWM Command signal to this pin. Refer to the following table for
input circuit specifications.
Pin 2 Remote Reset/Start Request
Apply a positive or negative voltage (±5–24 VDC) with respect to Pin 11, Input Common, to
disable the laser. The laser remains disabled while voltage is applied to this pin. Removing
voltage from the Remote Reset/Start Request pin causes the laser's RDY indicator to illuminate
and begins a five-second countdown after which lasing is enabled. Because all DC power is
removed from the laser's RF board when this input is active, no lasing can occur until voltage is
removed from Pin 2. Refer to Table 3-4 for input circuit specifications.
Important Note: Note: To prevent operator injury when using Keyswitch-equipped lasers, the
Remote Reset/Start Request signal is ignored when the Keyswitch is set to the OFF position. The
manually operated Keyswitch must be set to the ON position before the laser can be reset or started
from a remote location.
Pin 3 Remote Interlock
Apply a positive or negative voltage (±5–24 VDC) with respect to Pin 11, Input Common, to
enable lasing. If your system does not use a remote interlock, this pin must be connected to a
voltage source in the range of ±5–24 VDC. Refer to Figure 3-7 for a diagram showing how the
Remote Interlock input is factory-jumpered. Because all DC power is removed from the laser's
RF board when this input is inactive, no lasing can occur until voltage is applied to Pin 3. Refer to
Table 3-4 for input circuit specifications.
On OEM lasers, the Remote Interlock input is not latched. Re-applying a signal to Pin 3 enables
the RDY indicator and lasing is possible after the five-second delay, provided that the Shutter
Open Request signal is also present (SHT indicator illuminated).
Pin 9 PWM Input
Connect your PWM Command signal (+5 VDC, 5 kHz nominal, 25 kHz max) to Pin 9. This pulse
width modulated Command signal controls laser output so that a duty cycle of 50% corresponds
to a laser output of approximately one-half rated output power and a duty cycle of 95%
corresponds to approximately full output power. Refer to Controlling laser power in this chapter
for further information on laser control signals. Connect the PWM signal source return to Pin 1,
PWM Return. See the following table for input circuit specifications.
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