Internal Protective Functions; Assuring Safe Operating Temperatures - Scanlab hurrySCAN 10 Installation & Operation Manual

2.3 Internal Protective Functions

Assuring Safe Operating Tempera-
tures
If the scanners are driven for long periods of time at
high positioning speeds or if the application includes
a high rate of vector changes, the correspondingly
high current consumption of the galvanometer scan-
ners can lead to excessive temperatures – especially in
the case of insufficient cooling, for instance due to a
weak thermal link to the machine.
To prevent damage to the scanners, the
®
hurrySCAN 10 provides a two-stage temperature
control mechanism.
Caution!
The user must ensure that the application
program evaluates the temperature control
signals correctly, as described below.
Stage 1: Temperature Status Warning
The temperature status signal TempOK indicates that
the scanner is operating at a safe temperature level.
During normal operation, the signal is 1.
If the scanner temperature rises above a certain value
or drops below a minimum value, then the TempOK
signal switches to 0. SCANLAB recommends to only
operate the scan system while the TempOK signal is
1. If the TEMPOK signal switches to 0 during opera-
tion, system operation should be stopped and the
system should be checked to determine the cause. If
system operation is not stopped, large drift or other
side-effects may occur.
The application program must repeatedly check
the TempOK signal during operation.
®
hurrySCAN 10, digital, 1064 nm, f = 254 mm
Rev. 2.6 e
®
2 The hurrySCAN 10 – Principle of Operation
Stage 2: Critical Temperature Shutdown
In addition to the temperature status warning, the
following scanner protective function is imple-
mented:
If a scanner's temperature rises above the critical
value for temperature status warning and reaches a
second, still higher critical value, then
• the PowerOK status signal switches from 1 to 0,
• the scanner's output stage is turned off to
prevent damage to the scanner. In this situation,
the scanner's position is stationary and no longer
under programmatic control.
If the scanner's temperature drops again below the
power-down threshold, the scanner's drive stage is
automatically restarted and the scan head will
resume normal operation.
Caution!
If the PowerOK signal switches to 0, laser
power must be switched off immediately.
Otherwise, health hazards and severe
equipment damage can occur due to uncon-
trolled laser radiation.
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