Campbell CCFC Field Camera, Инструкция по эксплуатации

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CCFC Field Camera
39
Figure 12-10 External Trigger
External Trigger can be configured to Active High or Active Low .
When set to Active High, 0 volts is the Inactive state and a
positive voltage is the Active state.
The CCFC is shipped from the factory with a pull down resistor
connected to the
External Trigger and the External Trigger is set
to Active High . With this default setting, when no signal is
applied to the input, the External Trigger is inactive. A positive
voltage is required to change to the active state.
The External Trigger can be configured for an Active High signal
or an Active Low signal. The capture is triggered by the transition
from the inactive state to the active state. The minimum required
pulse period is 10 milliseconds (msec). Preferably, pulses should
be short in duration (milliseconds). No less than 1 sec between
captures is recommended with no more than 5 in a 10 second
period.
The voltage levels are:

Low Level: <0.65 V (-20 Vdc Absolute Min)

High Level: >2.0 Vdc (+20 Vdc Absolute Max)
Leaving the External Trigger signal in the active state prevents
the camera from entering into a low powered state. If an external
device is allowed to keep the camera in its
Fully On State , power
consumption will be greatly affected.
When the camera is fully on and no other process is occurring,
the time from the transition of the signal from inactive to active,
to the time a picture is captured or video is started, is typically
less than 100 msec. The parameter descriptions for the
External
Trigger setup are outlined in Tables 12-6 and 12-7 External
Trigger Variables for Photos and External Trigger Variables for
Videos, respectively.