Ground Testing RRC3+ using a vaccuum and jar

[Annalyn Connor]

I have the RRC3+ inside of a cup with a little hole on the side to read the pressure differential. I attached the vacuum head to the top of the jar and sealed it with tape and a latex glove lol. The screw switch and electronic match are outside of the cup to turn it on easily. Whenever I try this test, nothing happens with the electronic switch. I turn on the vaccuum, turn it off and wait for the pressure to reach whatever it is (at 500 ft is the preset). I didn't buy the cord that is used to program the main and drogue via USB because it was such a specific part and kinda expensive. I know my setup looks rough but it should work, not sure what I'm doing. This is a plug and play altimeter and just trying to ground test this before with an electronic match and 4F. Any advice would be amazing! I was using a glass jar but realized I didn't have a hole on the side, so I added that thinking that would solve the issue maybe a balloon?

 

[Hobie1dog]

Welcome to the forum, I cannot to open your file

 

[pathtouch]

I wonder if the glove is getting sucked closed and preventing the vacuum from reaching then cup. Can you just use a more rigid lid?

 

[Voyager1]

What deployment mode are you using? The default is Mode 1 for dual deployment, but you’re only using 1 ematch. Are you getting the correct continuity report after power up? Try setting it to Mode 3 for apogee only deployment if you’re only using 1 ematch.

 

[loopy]

What deployment mode are you using? The default is Mode 1 for dual deployment, but you’re only using 1 ematch. Are you getting the correct continuity report after power up? Try setting it to Mode 3 for apogee only deployment if you’re only using 1 ematch.

This would be my guess. It's looking for continuity on all fronts, and if you only have one ematch hooked up, it's not going to work the way you want it to.

 

[user 30299]

Here is a simple vacuum chamber that I use to test my flight controllers. That's an RRC3 in the pictures.

That's a luncheon meat container. You can also buy a similar food storage container at any supermarket.

That's just a plain old plastic straw with pieces of masking/painters tape to hold it in place. All you do
is drill a snug-fitting hole in the lid. The lid does not need to be sealed with tape or silicone.

If you can find a couple of LED bulbs, then use those in place of the e-matches.

All you have to do is suck on the straw and you will pull a near vacuum, hold your breath, and then
let air bleed back in. You will see the LEDs light up.

 

[user 30299]

What deployment mode are you using? The default is Mode 1 for dual deployment, but you’re only using 1 ematch. Are you getting the correct continuity report after power up? Try setting it to Mode 3 for apogee only deployment if you’re only using 1 ematch.

It's for sure not working correctly if it's looking (checking) for two e-matches.

Also using a shop vac (?) on such a small "chamber" I wonder if it would overwhelm the sensor and sampling speed ?

 

[Titan II]

Scratch the glove. The container must be solid. Does the glass jar have a lid? Drill or punch a hole in it for the vacuum tube and wires. Seal with glue, puddy, etc. The RRC3 is ready to go out of the box. Just leave the dip switches where they were. "Modes" as mentioned above have nothing to do with it. BTW...I have about a dozen RRC3s and a few RRC2s, and never vacuum tested any of them. They all worked out of the box.

Attachment does not work.

 

[David Schwantz]

I use a big syringe on mine. And a Mason jar with a metal lid.

 

[mack]

Here is a simple vacuum chamber that I use to test my flight controllers. That's an RRC3 in the pictures.

That's a luncheon meat container. You can also buy a similar food storage container at any supermarket.

I did this as well and it worked great...

 

[user 30299]

BTW...I have about a dozen RRC3s and a few RRC2s, and never vacuum tested any of them. They all worked out of box.

Usually when you see a request on the vacuum testing it's typically a high school or university team, and the
individual is tasked with doing a bench test of the flight computer. Quite common.

That's what pushed me into setting up this simple chamber. Keep it on hand for the teams.

 

[Art Upton]

I do the test in my Ebay it is going to be mounted in.. I am glad I do as one time I built the ebay wrong and it had a leak in it and would not draw a vacuum. I put the altimeter into the ebay, put the VAC on the altimeter hole, then pull it off and the ematch pops.

I'm using the PF Stratto loggers.

 

[pathtouch]

Here is a simple vacuum chamber that I use to test my flight controllers. That's an RRC3 in the pictures.

That's a luncheon meat container. You can also buy a similar food storage container at any supermarket.

That's just a plain old plastic straw with pieces of masking/painters tape to hold it in place. All you do
is drill a snug-fitting hole in the lid. The lid does not need to be sealed with tape or silicone.

If you can find a couple of LED bulbs, then use those in place of the e-matches.

All you have to do is suck on the straw and you will pull a near vacuum, hold your breath, and then
let air bleed back in. You will see the LEDs light up.

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I love the simplicity of this. I feel like I over engineered mine haha

 

[user 30299]

I love the simplicity of this. I feel like I over engineered mine haha

I think it was John Beans (of Jolly Logic fame) that put me onto the luncheon meat container a few years ago.

Credit goes to John on planting the seed . . .

 

[user 30299]

I have the RRC3+ inside of a cup with a little hole on the side to read the pressure differential. I attached the vacuum head to the top of the jar and sealed it with tape and a latex glove lol. The screw switch and electronic match are outside of the cup to turn it on easily. Whenever I try this test, nothing happens with the electronic switch. I turn on the vaccuum, turn it off and wait for the pressure to reach whatever it is (at 500 ft is the preset). I didn't buy the cord that is used to program the main and drogue via USB because it was such a specific part and kinda expensive. I know my setup looks rough but it should work, not sure what I'm doing. This is a plug and play altimeter and just trying to ground test this before with an electronic match and 4F. Any advice would be amazing! I was using a glass jar but realized I didn't have a hole on the side, so I added that thinking that would solve the issue maybe a balloon?

You may want to consider getting the Bluetooth Module - it's less expensive than the USB dongle.

The Bluetooth module makes it a good bit easier to program the RRC3 vs. tapping the button and flipping the switches.

You can also access the flight log, get all your launch info, and graph the launch.

 

[user 30299]

I love the simplicity of this. I feel like I over engineered mine haha

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It you look too quickly - it looks like you're performing an Alien Bug experiment.