NI 9477 Peak Current Rating

[WillD]

I tried to locate a datasheet for the output transistor arrays on the NI9477 32 channel sinking output module for the cRIO with no avail.  I am trying to find the peak current rating for this device, the datasheet claims 1A continuous per channel.  I have ran 1 output at 3A, 50ms on 950ms off, for 40,000 cycles with no problems so far.

My application may call for 32 channels at 3A for 50ms on with usually at least a minute off.

Best Regards,

William

[Jennifer_R]

Hi William,

The maximum continuous current output for the NI 9477 is 20 A total, 1 A per channel.  This can be found in the NI 9477 Operating Instructions and Specifications.  As explained on page 8 of the manual, channels can be used in parallel if more than 1 A is needed. 

[WillD]

I understand the peak continuous current for a single channel is 1A.  However, I am trying to realize the peak pulsed current rating for one channel.

[Jennifer_R]

Hi William,

Unfortunately there are only specifications for continuous output when using the NI 9477.  While, as you have seen, a higher current may be possible for small amounts of time, operation above 1A cannot be guaranteed.