System-Related Functions
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The default function is protection state indicator. IO-3 pin will output high or low
level based on whether the instrument is under protection or not. Under normal
conditions (Not under protection), and when pin3 is under default setting (Not
Invert), pin 3 outputs high level; when the instrument is under protection, pin 3
outputs low level. When pin3 is set to Invert, the output level is completely
opposite.
Digital IO-4
IO-4 pin can be set to【Sync-in】, 【Sync-out】,【Input】,【Output】
This function can be used to simulate the six-phase output mode, in which one
IT7900 outputs a synchronous signal to another IT7900, and the second power
supply runs synchronously with the frequency and phase of the first power
supply to realize the six-phase output function.
【Sync-in】: Synchronous input function, which is used to output frequency lock
or phase lock with the external signal. At this time, the machine synchronizes
the frequency or phase information input from the IO-4 pin.
【Sync-out】: Synchronous output function, the IT7900 produces synchronous
signal to the outside, which is AC zero crossing pulse signal sent from the IO
port.
Digital IO-5
IO-5 can be set to 【OnOff-status】, 【Input】, 【Output】
The default function is to indicate the output state of the power supply, in case
of output is ON, output 5V, otherwise, output 0V.
When pin5 is set to Invert, the output level is completely opposite.
Digital IO-6
IO-6 can be set to【Trigger1-in】, 【Trigger1-out】, 【Input】,【Output】
【Trigger1-in】: The input trigger signal, the pulse signal sent to the IO-6 pin can
be used as the trigger source. Users can select as the trigger source of the
corresponding function in the menu.
【Trigger1-out】: The output trigger signal, when the instrument generates a
trigger signal, the pin6 generates an pulse signal.
Digital IO-7
IO-7 can be set to【Trigger2-in】, 【Trigger2-out】, 【Input】,【Output】
【Trigger2-in】: The input trigger signal, the pulse signal sent to the IO-6 pin can
be used as the trigger source. Users can select as the trigger source of the
corresponding function in the menu.
【Trigger2-out】: The output trigger signal, when the instrument generates a
trigger signal, the pin7 generates an pulse signal.
7.13 Analogue Function (Ext-Program) (Optional)
The interface expansion slot provided on the rear panel of the IT7900P series.
This function is not standard with the instrument and is optional for users.
When the interface card selected by the user is RS232+Analog interface (IT-
E177), the analog interface can realize the external analog function.