Raytec PULSESTAR VTS Series, Руководство по установке

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General description
The VTS current controller provides repeatable intensity and timing control for
its strobe lighting. Two modes of operation are provided for the light output:
Pulse (strobe) — the output is pulsed once per trigger. One trigger input is used
as a trigger. The delay from trigger to pulse, the pulse duration and the
brightness can all be set.
Switched — a trigger input can be used to switch the output current on and
off. The sense of the trigger signal can be active high or active low.
The set-up is non-volatile, so the VTS will resume the same operation after a
power cycle.
7.1
Pulse and duty cycle limits
In both pulsed and switched mode, the pulse width and duty cycle are internally
limited to prevent damage to the light.
The brightness can be set up to 100%, but only for short periods and at low duty
cycles, so that the lighting does not damage itself by overheating. In pulse mode,
the duty cycle is limited by ignoring triggers which occur too soon after the
previous trigger.
The brightness, pulse width, and duty cycle can all be set, as shown in the table
below:
Output
brightness
850nm Variant White Variant
Allowed pulse
width Allowed duty
cycle Allowed pulse
width Allowed duty
cycle
0% to 20% 3ms 6% 3ms 3%
21% to 30% 3ms 6% 2ms 2%
31% to 50% 3ms 3% 2ms 2%
51% to 100% 1ms 2% 1ms 1%
For example, if the brightness is set to 40%, then a VTS20-850 will not allow
pulses longer than 3ms.
With 1ms pulses, if a trigger occurs less than 33ms after a previous trigger (so that
the duty cycle would be greater than 3%), the trigger is ignored.
If necessary, the VTS limits the duty cycle by increasing the re-trigger delay.
When the VTS internal temperature gets too high, the allowed duty cycle is reduced,
and an
Event 149 code is generated.
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