National Instruments NI 1450 Series 用户手册

© National Instruments Corporation

An example of using general-purpose outputs is driving a relay that turns 
on an Inspection in Progress light for an operator to see while the inspection 
sequence is running.

The NI 1450 recognizes the following fault conditions:

•

External shutdown, when Shutdown mode is enabled

•

Watchdog expiration, when configured for system shutdown

•

Overheat

The behavior of the NI 1450 in the event of a fault condition is dependent 
on configuration settings of the SAFE MODE DIP switch and the 
software-enabled Shutdown mode.

To resume operation, address the fault condition and reset the NI 1450.

The following sections describe each fault condition, and Table 4-4 
summarizes how user configuration affects the behavior of the NI 1450 
in the event of a fault condition.

Shutdown mode is a software-enabled feature that when activated allows 
an external device to halt the NI 1450 processing operations. Additionally, 
enabling Shutdown mode allows you to specify user-defined shutdown 
states for all fault conditions.

When Shutdown mode is enabled and the shutdown input signal, 
ISO Input 11, turns off, the NI 1450 registers an external shutdown 
condition. When this fault occurs, the POWER OK LED turns red and all 
system operation halts. To resume operation, you must reset the NI 1450.

For all fault conditions, outputs operate according to user-defined 
shutdown states. Each TTL output is configurable to drive high, drive low, 
or 3-state, and each isolated output is on/off configurable. 

Because the NI 1450 cannot run VIs in Safe mode, Shutdown mode is 
unavailable when the SAFE MODE DIP switch is turned on. 

Refer to Table 4-4 for a summary of how user configuration affects the 
shutdown condition.