Using a bench power supply for cRIO

[Shinigami2057]

Is it safe to use a bench power supply to power the cRIO without the PD board? The power supply I will be using has the same current limits as the PD board for the 24V boost power supply.

Failing that, would a 24V DC adapter work without harming the cRIO?

[wilsonmw04]

Originally Posted by Shinigami2057

Is it safe to use a bench power supply to power the cRIO without the PD board? The power supply I will be using has the same current limits as the PD board for the 24V boost power supply.

Failing that, would a 24V DC adapter work without harming the cRIO?

I think it's been said several times that using the cRio with a bench supply is not advised. Folks, feel free to correct me if I'm wrong.

[KevinReid]

I would be very nervous about doing it, but if you cant afford another power distro board... I guess you take your chances if required.

Good Luck, be extra safe.

[EricVanWyk]

Originally Posted by wilsonmw04

I think it's been said several times that using the cRio with a bench supply is not advised. Folks, feel free to correct me if I'm wrong.

Powering the PD with a bench supply is not supported. This means that it is possible to make it work, but we will not put any effort in to fixing "bugs" that occur when it is thusly powered. For example, a request that says "When powering the PD from a power supply the WiFi cuts out" will be answered with "Use a battery instead".

NI sells an AC/DC adaptor for the cRIO, but I don't think there is anything special about it. Take a look at the cRIO manual on the NI website.

[Al Skierkiewicz]

Harry,
Using a bench supply for just the Crio should be OK. When you couple a bench supply to the PD and then try to feed some motors, there will be problems with drooping PD supply and thus the Crio reboots. Although you may find a high current power supply that is good to 35 amps peak like my Ham station power supply, it cannot handle the short circuit current of most motors in the KOP. The bench supply will go into current foldback or complete shutdown when trying to start one of these motors.

[Shinigami2057]

Originally Posted by Al Skierkiewicz

Harry,
Using a bench supply for just the Crio should be OK. When you couple a bench supply to the PD and then try to feed some motors, there will be problems with drooping PD supply and thus the Crio reboots. Although you may find a high current power supply that is good to 35 amps peak like my Ham station power supply, it cannot handle the short circuit current of most motors in the KOP. The bench supply will go into current foldback or complete shutdown when trying to start one of these motors.

Yes, I was just planning on attaching the cRIO, not the PD board (or any other load for that matter) - I know that's a very bad idea. I've had success in previous years with attaching the previous control system to a bench supply, but I wanted to double-check to make sure there wasn't any danger of damaging the cRIO.

Any team who left the PD unit behind is braver than we are; there's no way we're going to reconnect all of our wiring after uncrating

Thanks for your quick responses!

[Al Skierkiewicz]

Harry,
You should check the NI website for info on the CRIO. I seem to remember that the unit can accept anything from 19 to 30 volts and has a specified current for that range depending on the modules you have installed.
If a little care is taken in tying down the wiring prior to removal, the new PD should be a much easier pull and install than previous electrical distribution. As always, wire coding or color tagging helps.

[EricVanWyk]

Originally Posted by Al Skierkiewicz

If a little care is taken in tying down the wiring prior to removal, the new PD should be a much easier pull and install than previous electrical distribution.

If it is hard to use the WAGOs, you are doing it wrong. You may want to ask around the pits to find people who have mastered the technique, since it is very hard to teach digitally. In person, you can teach it in a few seconds.

[Alex698]

Originally Posted by EricVanWyk

If it is hard to use the WAGOs, you are doing it wrong. You may want to ask around the pits to find people who have mastered the technique, since it is very hard to teach digitally. In person, you can teach it in a few seconds.

I think he means that if you tied your wires down neatly and orderly, removing and replacing the PD board should be easy.

[EricVanWyk]

Originally Posted by Alex698

I think he means that if you tied your wires down neatly and orderly, removing and replacing the PD board should be easy.

Looking back at my post, I can see how you could have miscontrued my intent. My intent was to agree with and add to Al's comment, not to offer him advice. Offering Al advice on wiring robots is a like offering V-Neun advice on transmissions.

Al's comment was two fold:
1) Do things cleanly to save time.
2) The new PD's design will also save time.

My comment was to reinforce 2), because some teams are still having trouble with it.