90074225 MOPS-Q QTH Lamp Pow er Supplies
Page 47
11.7 EXTERNAL SHUTTER CONTROL METHODS
The BNC connector labeled
“TRIGGER INPUT” on the rear panel may be used to remotely control
the operation of a shutter that is connected to the power supply. A TTL signal may be applied to
the Trigger Input connector, or a remote switch closure may be wired to the connector.
If the shutter function is set to Timed or Dosed mode and a TTL signal is sent to the Trigger Input
connector, the first falling edge (high to low) triggers the start of a Timed/Dosed exposure cycle.
The Low pulse must be at least 70 milliseconds long to trigger the cycle. The Timed/Dosed cycle
then runs to its conclusion and disregards any additional signals received at the Trigger Input
connector while the cycle is in progress.
If the shutter is set to Manual mode and a TTL signal is sent to the Trigger Input connector, the
shutter remains open for the duration of the Low signal.
Figure 24 Trigger Example
By default, the shutter opens when a TTL Low signal is sent through the Trigger Input connector. The
power supply setup may be changed to allow an external TTL High signal to open the shutter. Changing
this setting is done through the System1 menu, as explained in
11.4 TTL SIGNAL POLARITY
of this
manual.
To avoid unexpected shutter behavior, this setting should be changed only when the shutter is closed and
no signal is being applied at the Trigger Input connector.
Note: If unsure of the correct TTL setting/shutter compatibility, the user should take all necessary
precautions against light exposure until the correct TTL setting/shutter compatibility has been
confirmed and the system is behaving as expected.