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Servo gear doors & pneumatic fail-safes.. HELP

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Servo gear doors & pneumatic fail-safes.. HELP

Old 04-05-2016, 05:24 PM
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BlueBus320
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Default Servo gear doors & pneumatic fail-safes.. HELP

How do you get the fail safe to talk to the gear doors??? I've come up with some nice 18mz P-mixes to get things working, but I"ve come to the realization that no matter what I mix or slave the Tams Failsafe does not talk to my TX (it does what it needs to do at the aircraft), so mixes will not help me with opening the doors in the event of an air leak "auto gear deployment". Is there a failsafe made that can talk to the Powerbox-Royal & allow me to use the integrated door sequence so that a leak will trigger the entire system?
Any help appreciated
Jay
Old 04-06-2016, 12:26 AM
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asimace
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Hi,
as far as I know if you are using programmed mixes on your transmitter you cannot achieve your goal with any kind of failsafe on the market.
The pneumatic gear failsafe, like the tamjets one you mention, can only pass the signal downstream to the sequencer/gear valve...
If you have programmed the sequencing in the transmitter, you would need a sensor to send back the air pressure to the transmitter in the telemetry stream and then set an alarm in the transmitter that would initiate the retract sequence.
Cannot do that I'm afraid.
However if you are using the built-in sequencer in the Powerbox and you are using multiple connections between RX and Powerbox (not single SRS connection) you can send the retract signal from RX to failsafe and then from the failsafe to the Powerbox.
The failsafe would then trigger the sequencer and retracts on the Powerbox.

Mauri

Last edited by asimace; 04-06-2016 at 12:38 AM.
Old 04-06-2016, 04:25 AM
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BlueBus320
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Originally Posted by asimace View Post
Hi,
as far as I know if you are using programmed mixes on your transmitter you cannot achieve your goal with any kind of failsafe on the market.
The pneumatic gear failsafe, like the tamjets one you mention, can only pass the signal downstream to the sequencer/gear valve...
If you have programmed the sequencing in the transmitter, you would need a sensor to send back the air pressure to the transmitter in the telemetry stream and then set an alarm in the transmitter that would initiate the retract sequence.
Cannot do that I'm afraid.
However if you are using the built-in sequencer in the Powerbox and you are using multiple connections between RX and Powerbox (not single SRS connection) you can send the retract signal from RX to failsafe and then from the failsafe to the Powerbox.
The failsafe would then trigger the sequencer and retracts on the Powerbox.

Mauri
Thanks Mauri. I am using the single connection to both rx's. I think I see a need for a new product. Using the Powerbox sequencer was Easy, but I have to figure out how to setup some sort of failsafe.
Jay
Old 04-06-2016, 05:42 AM
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mr_matt
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I think you can do this with Jeti telemetry. And you can have an alarm with ASSI telemetry
Old 04-06-2016, 07:08 AM
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One other solution would be to use two of Tam's failsafe units, the first one set at a slightly lower pressure to open the gear doors first in the case of an air leak, then the second one lowering the gear.
Old 04-06-2016, 08:58 AM
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BlueBus320
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Thanks guys, Mr Matt I've been looking at the ASSI device since it came out. I'll shoot those guys a message & see how that could work with Futaba.
Rslstft, each servo controlled door goes into a separate port of the Powerbox & then gets controlled via the integral sequencer. I don't think there is a way to get the TJ Failsafe to control the doors in this type of config, although I really like your thinking! Put that one in the back pocket for later
Jay
Old 04-06-2016, 02:00 PM
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wfield0455
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Originally Posted by mr_matt View Post
I think you can do this with Jeti telemetry. And you can have an alarm with ASSI telemetry
Yup. I have an air pressure sensor and use a telemetry control in my JEti DS16 to open the doors and drop the gear if air pressure drops below 50PSI. I also have a logical switch tied to the same control so that if the gear failsafe activates, it also enables the nose wheel steering which is normaly disabled when gear is up.
Old 04-06-2016, 02:20 PM
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Why not use a separate gear & door sequencer downstream of your failsafe? Or better yet look into the Jet Central sequencer/failsafe combo unit.

http://www.dreamworksrc.com/catalog/...Dual-Sequencer
Old 04-06-2016, 04:31 PM
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mr_matt
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Yes you could just use an onboard sequencer with the aipressure sensor upstream of the sequencer.

I used http://www.jet-tronics.de/doorsequencer_en.html
Old 04-06-2016, 07:04 PM
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BlueBus320
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Thanks for the suggestion guys. It sucks having to use a separate sequencer when the powerbox's works so well, but I think a separate sequencer/failsafe is by far the easiest, most reliable thing to do. Here's what I'm finding so far:
1. I don't think the Jettronics has a fail-safe function (from what I saw so far).
2. Jet Central looks good. I'm trying to find out the weight now, but it is pricey & looks a lil heavy
3. I'm looking at a Xicoy unit now, looks really small & light & has a built in Fail Safe & telemetry for $125.
Either way guys, thanks a million!
Jay
Old 04-06-2016, 07:15 PM
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bluebus, I have both a the JC and the xicoy, the xicoy is a pain to figure out the programming but its nice smal and light. The telemetry is simple to setup on futaba as well, only issue is the pressure reads as a temp so 100psi reads as 100c.
The JC is bigger but has some extra features like canopy and light control and does everything the xicoy minus telemetry. It is much easier to program for sure, if you need one im going to be listing mine on rcu it was only opened and checked hasnt seen any flying yet.
Old 04-06-2016, 09:40 PM
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I think you can do this with Jeti telemetry.

Last edited by miguestner; 04-06-2016 at 09:43 PM.

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