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cRIO module failure: max current

One of our cRIO modules ist currently going through several certifications and among these is IEC-62368. For IEC-62368 the energy source feeding the module has to be classified (e.g. less than 15 W = PS1).
I searched the cRIO documentation "NI cRIO-9951 - CompactRIOTM Module Development Kit User Manual" and found no rules regarding power/current limiting on the controller during normal use or module failure.
There is a rule that gives a requirement for the signal lines (3-6):

RULE—Carrier output buffers shall not be able to sink more than 200 mA when shorted to VCC, and shall not be able to source more than 140 mA when shorted to ground.


Is there any specification on the max. current that a cRIO controller/carrier is allowed to feed into a module on the VCC supply rail?
Maybe the controller itself has no such requirement, but maybe NI states that the external power supply for the controller (ext. power supply -> controller -> cRIO module) must meet requirements like x Watts max or must be a limited power supply (LPS).
How do the cRIO controllers behave during "overcurrent" (> 200 mA) conditions on the module supply rail? The inrush requirements indicate that above 200 mA the module can only "count" on a certain amount of bulk capacitance on the controller. Can we assume certain things about the controller, like current limited power regulation or are there safety measures like fuses?

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Hello engineer42

As a Rule, I found that, modules are limited to drawing no more than 200 mA from the carrier, they may dissipate additional power from an external source subject to the thermal limitations in the Thermal Requirements for C Series Platform section below. 



The specifications for C Series modules are as follows:
• Protection of module components (85 ºC and 100 ºC rated
• Maximum specifications (–40 ºC to 70 ºC system ambient)
• Typical specifications (23 ºC ±5 ºC system ambient)
• Standard typical specifications (–40 ºC to 70 ºC system ambient)
• Maximum temperature rises of 20 ºC for thermally sensitive modules
(–40 ºC to 70 ºC system ambient)
Modules, controllers, and backplanes thermal requirements are based on
the following characteristics, as shown in Figure 5-4:
• Maximum power dissipation during protected fault conditions
• Maximum power dissipation during normal operation
• Typical power dissipation during normal operation


Also, try to avoid doing overcurrent, because it can cause a hardware issue. 


As a reminder I want you to know, that this hardware is quite old, and articles are archived ass well, which is the main problem for less information about this hardware.




Best way to thank is giving Kudos/Marking as a solution

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