Revision to Tripoli Rule Regarding Wireless Remote Switches

The Rocketry Forum

Help Support The Rocketry Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.
Status
Not open for further replies.
You're welcome. I'm not sure, but I think they use some kind of electromechanical switch when they switch on internal power in "real" rockets... I'm sure some of the aerospace guys can chime in on this.
All the AMRAAMs, Sparrows, Sidewinders & HARMs I've shot were powered on when I took off. AeroAggie may have some further comments on that. He & I both have friends designing & flying manned rockets we could ask. Granted, we're talking about our hobby/business things here. Not to put words in your mouth, but I'm guessing you're of similar mindset: what electronic solution would satisfy the rules (or a waiver to the rules)?
 
Hey, don't imply I'm smart enough to join this conversation! :( I'm just a dumb structures guy waiting for someone to clarify what the minimum equipment list looks like in order to use a magnetic switch. My interpretation so far is that a magnetic switch does not comply with safety code when used as the only means of switching power to an energetics circuit. Like Groucho, I'm moving away from screw switches to magnetic for *safety* reasons, so it's back to the drawing board for the rocket I'll describe below:

I'm designing a record-attempt minimum diameter rocket with three electronic devices in it - Telemetrum, Easy Mini, and Featherweight Tracker - each switched by a Featherweight magnetic switch and its own battery; Redundant altimeters and redundant trackers.
Due to the high performance nature of the design, I do not want external switches (drag) or extra holes in the airframe (drag), nor do I want to be trying to re-stuff chutes and charges in an extremely volume-limited airframe out at the pad (unecessary risk, "hurry up and rock your rocket so we can launch"). If test flights are successful, then this design was also intended to be the basis for a minimum diameter Level 3 project.

I think the compliant path forward for me will be to use existing airframe vents to poke a mechanical switch and close charge circuits, but keep the magnetics for electronics power. Unfortunately, the limited design space in the nose cone means I will likely have to give up a redundant tracker or altimeter. I'm sure one could argue that it's technically safer to bystanders, but it increases the risk that I do not get my rocket back.
 
All the AMRAAMs, Sparrows, Sidewinders & HARMs I've shot were powered on when I took off. AeroAggie may have some further comments on that. He & I both have friends designing & flying manned rockets we could ask. Granted, we're talking about our hobby/business things here. Not to put words in your mouth, but I'm guessing you're of similar mindset: what electronic solution would satisfy the rules (or a waiver to the rules)?

Are you implying that military firing systems can be any way comparable to our hobby rocket electronics in design, FMEA practice, manufacturing quality and testing processes?
 
I definitely understand where Tripoli is coming from - it’s not hard for a random Jane to make their own WiFi/ZigBee/other wireless firing circuit with an Arduino — and it’s quite easy to do it badly. Most microcontroller hobbyists go about splicing completely unrelated pieces of code they found using Google.

I don’t think the RSO should have to trust that some random person they’ve never seen before has well designed electronics & software.

There’s no way the RSO can know prior to inspection if a flyer didn’t just cobble together Arduino scraps before inspection, and he definitely shouldn’t have to blindly trust it won’t fire an engine or charge until it’s on the pad.

All very true. But not what we are talking about here. We're talking about a reversal of policy on a handful of previously reviewed devices.
 
The are similar codes in UL with regards to thermal and overcurrent requirements. Hardware fuses are required. You cannot just rely on firmware and electronics to protect against overtemps and overcurrent faults.

In my refinery research work, all our overtemp controls are microprocessor based. The standard is that it can't be the same microprocessor as the PID loop. We buy CE rated equipment that's built to the same standard. They are tested at installation and then trusted for years. I once had to remove mechanical overtemp devices - mostly because they didn't latch. We tend to trust tested electronics and distrust sensors. Intensely.

To comment on the next post, too; it's not that I blindly trust software - but I do consider it a separate point failure from the hardware it runs on, or the IO system it's connected too. In my day-job, the example I've been involved with was a PC based system that controlled multiple gas and liquid flow rates and had to avoid flammability envelopes. I did my best to break it during testing with inert gasses. Still makes me edgy.
 
Steve, from Post #1:

Those circuits which include Tripoli approved wireless remote switches may have the physical disconnections reconnected once the rocket is out on the range (either near the pad or at a special preparation area), thus transferring control to the remote switch.. Although the rocket must be pointed in a safe direction at all times, it is not required to have the rocket on the pad and vertical when the mechanical connections are made if the wireless remote switch is in its safe state. The rocket must be on the pad and upright and all personnel must be at a safe distance away from the pad when the wireless remote switch is commanded closed.

The above means that you can have a piece of electronics - a combination of WiFi and altimeter - that can be energized with the rocket horizontal, and with "physical disconnections reconnected". You would then be raising a rocket with energized electronics connected directly to the igniter. Although the "switch", which isn't a switch at all, would be armed remotely from its "safe state" while vertical, raising a rocket in this condition is not something that I would recommend doing. I understand the intent of the rule, but it looks to me like an overly simplistic fix for what is a complex problem. I don't think it is prudent to raise a staged rocket unless the igniter is either properly shunted or disconnected, particularly if it is connected to an energized piece of electronics.

Jim

Thanks, Jim. Now I understand your concern.
 
Hey, don't imply I'm smart enough to join this conversation! :( I'm just a dumb structures guy waiting for someone to clarify what the minimum equipment list looks like in order to use a magnetic switch. My interpretation so far is that a magnetic switch does not comply with safety code when used as the only means of switching power to an energetics circuit. Like Groucho, I'm moving away from screw switches to magnetic for *safety* reasons, so it's back to the drawing board for the rocket I'll describe below:

I'm designing a record-attempt minimum diameter rocket with three electronic devices in it - Telemetrum, Easy Mini, and Featherweight Tracker - each switched by a Featherweight magnetic switch and its own battery; Redundant altimeters and redundant trackers.
Due to the high performance nature of the design, I do not want external switches (drag) or extra holes in the airframe (drag), nor do I want to be trying to re-stuff chutes and charges in an extremely volume-limited airframe out at the pad (unecessary risk, "hurry up and rock your rocket so we can launch"). If test flights are successful, then this design was also intended to be the basis for a minimum diameter Level 3 project.

I think the compliant path forward for me will be to use existing airframe vents to poke a mechanical switch and close charge circuits, but keep the magnetics for electronics power. Unfortunately, the limited design space in the nose cone means I will likely have to give up a redundant tracker or altimeter. I'm sure one could argue that it's technically safer to bystanders, but it increases the risk that I do not get my rocket back.

I’m sorry. I know this makes it more difficult and I do understand the comments about restuffing the rocket at the pad. What about using a table at a special preparation area out on the range where you could go after the RSO table and reconnect the batteries and stuff the chutes?
 
Are you implying that military firing systems can be any way comparable to our hobby rocket electronics in design, FMEA practice, manufacturing quality and testing processes?

If the heart of the matter is design, analysis, and testing, then no. But then the path would be laid out to come up with a 'like' process of appropriate degree, while knowing we aren't going to similar in degree. Nor need to be. Or maybe need to be only above a specific impulse/grams of pyro.

If the heart of the matter is that electronic control prior to pad will never be accepted by the BoD, no matter the design, analysis, and testing - well, then. There you are.

As I thought about my prior responses, and think about my day-job process safety standards, I'm coming to see that the testing aspect may be the hardest to satisfy. How would you approach an RSO and show them that the appropriate tests (assuming they were identified) have been done? (And I'm thinking even working out the tests isn't easy - for instance, prove that the minus-side control on a Proton hasn't failed closed, nixing your redundancy. And how often do you do that test?) Signed checklist? Puh-lease. Deputy RSO comes to your prep area and watches the test done on lights instead of charges/starters? Maybe - but that would be a huge resource ask.

The simple answer from the club side is to revert to prior practice - power up with the rocket away from most people and pointed in a safe direction.

In pondering JimJ's thoughts on what counts as a safe direction, I keep coming back to the 'whole system'. I count ladders as manifestly unsafe. If it took a ladder to reach the mechanical switches, I'd MUCH prefer redundant electronics I had tested prior to connecting to pyros. I don't personally fly anything that needs ladders, though.
 
Last edited:
Oy... people already have pitchforks out because the devices they own haven’t been past a review board (yet). I’d hate to think what would happen if UL and/or IEC certification is required.

That said, I’m 100% onboard requiring certification for electronics, pitchforks or no.

I have been sent to the hospital (not rocketry related) because an “impossible” situation with microcontroller controlled machinery - I had physically disconnected the power source that closed an actuator. It was “supposed” to be dead. But the system wasn’t perfect (none is). The actuator couldn’t close, but sure could open! And it crushed my finger. It took weeks to get the rest of the engineering team to see that what they thought was impossible had, in fact, happened.

I definitely understand where Tripoli is coming from - it’s not hard for a random Jane to make their own WiFi/ZigBee/other wireless firing circuit with an Arduino — and it’s quite easy to do it badly. Most microcontroller hobbyists go about splicing completely unrelated pieces of code they found using Google.

I don’t think the RSO should have to trust that some random person they’ve never seen before has well designed electronics & software.

There’s no way the RSO can know prior to inspection if a flyer didn’t just cobble together Arduino scraps before inspection, and he definitely shouldn’t have to blindly trust it won’t fire an engine or charge until it’s on the pad.

I’m 100% behind keeping electronics that light a pyro dead until on the pad.

My entire career in software has been fixing problems caused by software whose designer only thinks of the “happy path,” and whose software can’t handle anything else.

I literally have the scars to prove it. If it can happen, it will. There is no escape from Murphy’s law.
I'm sorry you went through that experience! I am in no way advocating for UL/IEC regulation of altimeter devices, but to establish rational criteria around what can or cannot be done within designs that would make them "safe" in the eyes of Tripoli (and I suspect NAR, since they will likely adopt a very similar or identical position). Not that Tripoli cares what I think, but as a guy who has spent his career in high tech, I really have an allergic reaction to their broad-brush position.
 
Is NAR or Tripoli approaching this from a DFMEA perspective? In life, there is no such thing as a zero probability event, so we manage risk through a thorough analysis of risk.

I mentioned the same thing earlier, and the answer was no- there isn't a formalized analysis (FMEA or otherwise) that we are aware of.

My other concern is that "risk mitigation" assumes a controlled environment where it's easy to design in safety features in the process, not just the hardware/software. The problem with this is that it requires people to be 1. Aware of the rules/process and 2. follow it properly. People can only remember so many things, and if we add another rule, a different rule will get forgotten or done incorrectly. So while I don't want to say "yeah, we're not going to do that", I would rather focus the priority on activities that have a high risk of occurring + high level of danger on the outcome.

Considering this is a hobby and not a manufacturing site, it's always going to be less controlled (by design).
 
Jim, what would be your proposed solution to this problem? Personally, I'd rather not be standing on a ladder fiddling around for some switch with my face inches away from several thousand Newton-seconds of potential energy... which is why I came up with the WiFi stuff in the first place.
First, let me offer my thanks to you for putting out the WiFi switch. I use them, and they keep me off the ladder (my WiFe likes that!).

But as I mentioned, the problem is more complex than just using the WiFi switch. In my opinion, raising a rocket with live electronics with a direct path to an igniter is not safe. I have mitigated the issue in several ways. First, where I can, I add a shunt to the igniter that can be in place at the time that the rocket is raised. If you think about it, there are lots of ways that this could be done depending on the creativity of the flier. One further benefit would be the ability to not remove the shunt until the rocket actually takes off. This also allows the shunt to be in place in the event that the rocket has to be lowered, and particularly if it has to be lowered in a case where the WiFi switch can't be turned off for some reason.

Another approach that I use, but that others may not, is to separate the WiFi power source from the altimeter. That is, use the WiFi switch but connected to something else, where you can tell if that something else is powered up or not after turning on the WiFi power. I haven't had any problems with your WiFi switches, other than connection problems from time to time, but I have had issues on at least four occasions with faulty programming and on two occasions with faulty hardware. I appreciate that these devices are available to me, but it is foolish to think that they are perfect out of the box or won't degrade over time. I am fine with your "combination" devices, and Tripoli's approach, for deployment charges, but for motor igniters, I want a little more.

Another approach I use is an all up test of the electronics just prior to flight (typically done with the igniter out), and I avoid head-end ignition unless there is no alternative. A final approach that I use is to raise the rocket remotely so that no one is around it in the event that there is an issue during that time or if the rocket accidently falls.

So, my only concern with the Tripoli action is that in an effort to make things safer, they appear to have santioned an approach that IMO is unsafe.

Jim
 
I totally agree with you Jim that the demand for mechanical disconnects ONLY unequivocally renders our sport more dangerous.
 
I am fine with your "combination" devices, and Tripoli's approach, for deployment charges, but for motor igniters, I want a little more.

I added the emphasis, as I find the distinction interesting.

Jim, out of curiosity, would you apply the same care for a H-G staged flight? H-H? Lvl 2 sustainer impulse?

I do like the thought you've given to -dis-arming.
 
Thanks Jim. I always do an all-up electronics test too, without the powder, and if it's a two-stager with the igniter out of the sustainer of course. It is certainly possible to use a separate power source for the altimeter, powered on by the WiFi Switch; I like that idea for high-risk loads (like staging an M motor... I'm not quite there yet). What kind of arrangement do you use for your shunts, and how can it be carried over to a lesser project (i.e. a garden-variety single-stage 3" 3FNC with a 54mm 4G motor, for example)?
 
I agree with Jim regarding staged rockets, this revision [or common practice] does not sufficiently address the need for an appropriate set of requirements specific to staging [or air starting]. Staging is indeed a complex problem, and the typical solutions will probably appear burdensome to many hobbyists, however just because people 'don't like it' or 'nothing has happened yet' [stuff has], does not mean it is inappropriate. TRA's change seems like a reasonable requirement for single stage, single ignition-event rockets, but staging still needs to be addressed.
 
The safety reports that Dr. Jay Apt did for NAR are all I know of. .

Actually, the NAR has an entire history of safety studies. Studies done for the NAR Board of Trustees prior to Jay and his team's work include:

1978 Model Rocket Motor Shipping Safety
1985 High Power Rocket Safety
1991 Burn Tests of Reloadable Motors
1992 Model Rocket Motor Burn Tests
1994 Overall Safety of Reloadable Motors
1995 Hybrid Motor Technology
1996 Safety Analysis of Manufacturers’ Maximum Recommended Liftoff Weight
1997 Radio Controlled Glider Safety Code Development
1999 Tests of Cleared Distance Required for High-Power Rocket Launches
1999 Implementation of the “Trained Safety Officer” program
2001 Model Rocket Safety Code End-to-End Review
2002 Standards and Testing Report on Water Rocket Safety Code
 
Unfortunately those studies are almost all about either motor performance/safety or model rockets. Only the "1985 High Power Rocket Safety" report might be valid for contemporary HPR purposes, and that was done a long time ago... when flashbulbs and mercury switches were commonly used. The 2005 NAR report "Launching Safely in the 21st Century" (which was not mentioned in your list) is an excellent analysis of launch procedures, unfortunately it also does not address electronics.
 
First, let me offer my thanks to you for putting out the WiFi switch. I use them, and they keep me off the ladder (my WiFe likes that!).

But as I mentioned, the problem is more complex than just using the WiFi switch. In my opinion, raising a rocket with live electronics with a direct path to an igniter is not safe. I have mitigated the issue in several ways. First, where I can, I add a shunt to the igniter that can be in place at the time that the rocket is raised. If you think about it, there are lots of ways that this could be done depending on the creativity of the flier. One further benefit would be the ability to not remove the shunt until the rocket actually takes off. This also allows the shunt to be in place in the event that the rocket has to be lowered, and particularly if it has to be lowered in a case where the WiFi switch can't be turned off for some reason.

Another approach that I use, but that others may not, is to separate the WiFi power source from the altimeter. That is, use the WiFi switch but connected to something else, where you can tell if that something else is powered up or not after turning on the WiFi power. I haven't had any problems with your WiFi switches, other than connection problems from time to time, but I have had issues on at least four occasions with faulty programming and on two occasions with faulty hardware. I appreciate that these devices are available to me, but it is foolish to think that they are perfect out of the box or won't degrade over time. I am fine with your "combination" devices, and Tripoli's approach, for deployment charges, but for motor igniters, I want a little more.

Another approach I use is an all up test of the electronics just prior to flight (typically done with the igniter out), and I avoid head-end ignition unless there is no alternative. A final approach that I use is to raise the rocket remotely so that no one is around it in the event that there is an issue during that time or if the rocket accidently falls.

So, my only concern with the Tripoli action is that in an effort to make things safer, they appear to have santioned an approach that IMO is unsafe.

Jim

Jim,
Would you be able to point me to, or possibly start a new thread with some different options for shunting igniters, and how these approaches can be used with the WIFI switches? I would guess that they could potentially be also used for ejection charges. What do they look like?
Thanks,
Dave
 
Got it. So the use of only a featherweight magnetic switch or featherweight powerperch would violate the safety code.
What about Featherweight magnetic switches? Are they a "physical switch"?
No, they are not.
After reflecting for a day, I have tons of mixed feelings about this whole thing. I can say that I was always a bit uncomfortable with FET switches, so much so that I changed magnetic switch products years ago to one that allowed physical power disconnect (see: https://www.rocketronics.de/shop/en/altimax-magswitch.html). Saying that, I have built multiple high performance minimum diameter rockets and using a non-intrusive arming mechanism is highly desired. Most of my designs of this ilk have all electronics in the nosecone, so in most cases all that is needed is to add a twist wire at the base of the nosecone before replacing, pinning and mounting on the rail or sliding into the tower. So for me, given the particular electronics I use, I can get by. It is sad for people like Adrian at Featherweight, as some of the innovative products he has produced, like the Perch, will be forced into obsolescence.

But by far, my biggest concern in this thread is the statement below. I think if this is the recommended solution from Tripoli, this isn't solving any problem, in fact, not only is complexity and a failure point being forced upon the rocketeer by adding a physical break point in the electronics reliability block diagram of their rocket, it simply moves the safety issue geographically to another point on the range, albeit less crowded (maybe) which is a good thing. But will it be less crowded? If the recommendation is going to be to add a prep table at some intermediate point leading to the pads, then think how slow and backed up the range will get, and subsequently, because we all want to be nice rocketeers and not delay others, how pressured and prone to mistakes the people at that prep table will be.
I’m sorry. I know this makes it more difficult and I do understand the comments about restuffing the rocket at the pad. What about using a table at a special preparation area out on the range where you could go after the RSO table and reconnect the batteries and stuff the chutes?
If you are going to commit to add another station out on the range, why not make it an "advanced" RSO station for those flights that are complex and have wireless or magnetic arming. If you look at Kloudbusters, and many other clubs, they do this already by having an RSO at the away cell. This advanced RSO table could be expanded to not just include the away cell, but also the category of complex rockets and electronics. If enforced correctly, you eliminate the injury risk to the majority of the people at a launch by only having a handful of the most experienced rocketeers at that RSO area at any one time; those that are fully aware of the heightened risk of what is being checked and flown in that alternate path to the pads. I personally would even accept signing an additional injury waiver when using that RSO location if it reduced the complexity of the electronics in my rocket (which I believe is also increasing risk, that has yet been measured by Tripoli).
 
....<snipped for brevity...> It is sad for people like Adrian at Featherweight, as some of the innovative products he has produced, like the Perch, will be forced into obsolescence.
....<snipped for brevity...>
Hmm, unless I missed something, I can still use either PowerPerch or magnetic switch if I add a physical interruption between the altimeter and the ejection charge. To me that means a solution as simple as having one leg of the e-match sticking out a vent hole, cutting it so it is physically disconnected, and then twisting it back together at the pad. Far less than ideal, but that would satisfy the requirement. And given the number of rockets I have that are minimum diameter with very limited space, that may be the only solution short of rebuilding the entire A/V bay.


Tony
 
I added the emphasis, as I find the distinction interesting.

Jim, out of curiosity, would you apply the same care for a H-G staged flight? H-H? Lvl 2 sustainer impulse?

I do like the thought you've given to -dis-arming.
I would design the same regardless of impulse, but I normally advise care starting at HP rockets.

Jim
 
Hmm, unless I missed something, I can still use either PowerPerch or magnetic switch if I add a physical interruption between the altimeter and the ejection charge. To me that means a solution as simple as having one leg of the e-match sticking out a vent hole, cutting it so it is physically disconnected, and then twisting it back together at the pad. Far less than ideal, but that would satisfy the requirement. And given the number of rockets I have that are minimum diameter with very limited space, that may be the only solution short of rebuilding the entire A/V bay.


Tony
You are right, you can do that, as long as you both open the circuit and shunt the e-match (see: https://www.rocketryforum.com/threads/the-theory-of-shunting.127267/#post-1477670), otherwise opening alone, even if using a proper switch, causes problems with potential static and other electromagnetic interference (see #2 here: https://www.pyromate.com/Basics-of-Electrical-Firing.htm). In my post I was referring to a power safing solution to remove the chance of the FET operating. In the case of the PowerPerch the only way to do that is by cutting board traces and tacking on wires. Unless of course, you want to go against the compact design of the PP altogether and have either the battery or Raven dangling to get at the power leads.
 
Last edited:
Unless I am missing something the only addition we need to make is a battery switch. Honestly, if I were to use a wifi switch I would still put in a battery switch to the wifi unit. Why drain your battery when you dont need to?
 
Thanks Jim. I always do an all-up electronics test too, without the powder, and if it's a two-stager with the igniter out of the sustainer of course. It is certainly possible to use a separate power source for the altimeter, powered on by the WiFi Switch; I like that idea for high-risk loads (like staging an M motor... I'm not quite there yet). What kind of arrangement do you use for your shunts, and how can it be carried over to a lesser project (i.e. a garden-variety single-stage 3" 3FNC with a 54mm 4G motor, for example)?
The nice thing about a shunt is that it can be pulled off to open the shunt (either after the rocket is vertical or upon liftoff). The video shows one way that I have done this, which I've used several times. But conceptually, all you need is a short wire connected to two posts on the way to the igniter. It isn't quite as easy as it sounds, but I would think the concept could be done for pretty much any rocket.

Jim

 
Jim,
Would you be able to point me to, or possibly start a new thread with some different options for shunting igniters, and how these approaches can be used with the WIFI switches? I would guess that they could potentially be also used for ejection charges. What do they look like?
Thanks,
Dave
I don't have time at the moment to go into detail on this, but I have posts that describe shunts for staging. I don't really see these as specific to WiFi switches, but it's just something that seems to me to go hand in hand. I'm not sure I would do this for ejection charges though.

In general, guidelines for shunts would be to reduce the current going to the igniter to the minimum possible. All of my staged igniters (and most of my ejection charges) go through a resistor designed to minimize the maximum current. For example, a 4V LiPo with a 2 ohm resistor and a 1.5 ohm igniter will reduce the firing current to a little over an amp. Without the resistor, you might instead have 3 amps instead. So, the resistor would reduce the current through the igniter by about a factor of 2-3, should be altimeter fire, which helps the shunt to work better. The shunt is then just a short wire of some sort with minimal resistance. It is not hard to calculate what the current through the igniter would be with the shunt attached, and you just want to be comfortably below the no-fire current. Then, you test the circuit using exactly the components and wire lengths that you plan for the flight. See the previous video for an example.

Jim
 
Unless I am missing something the only addition we need to make is a battery switch. Honestly, if I were to use a wifi switch I would still put in a battery switch to the wifi unit. Why drain your battery when you dont need to?
That's actually a pretty good point... the trick is how to do it with an existing AV bay that was built wirelessly. I predict that we're going to be seeing a lot of twist and tape this Spring... which honestly is not a good thing from a reliability point of view.
 
Actually, the NAR has an entire history of safety studies. Studies done for the NAR Board of Trustees prior to Jay and his team's work include:

1978 Model Rocket Motor Shipping Safety
1985 High Power Rocket Safety
1991 Burn Tests of Reloadable Motors
1992 Model Rocket Motor Burn Tests
1994 Overall Safety of Reloadable Motors
1995 Hybrid Motor Technology
1996 Safety Analysis of Manufacturers’ Maximum Recommended Liftoff Weight
1997 Radio Controlled Glider Safety Code Development
1999 Tests of Cleared Distance Required for High-Power Rocket Launches
1999 Implementation of the “Trained Safety Officer” program
2001 Model Rocket Safety Code End-to-End Review
2002 Standards and Testing Report on Water Rocket Safety Code

Thanks! I’m very grateful that the NAR did those. I should have said Dr. Apt’s report was the most recent that I knew of, but I really didn’t realize the number of safety reports they did.
 
You are right, you can do that, as long as you both open the circuit and shunt the e-match (see: https://www.rocketryforum.com/threads/the-theory-of-shunting.127267/#post-1477670), otherwise opening alone, even if using a proper switch, causes problems with potential static and other electromagnetic interference (see #2 here: https://www.pyromate.com/Basics-of-Electrical-Firing.htm). In my post I was referring to a power safing solution to remove the chance of the FET operating. In the case of the PowerPerch the only way to do that is by cutting board traces and tacking on wires. Unless of course, you want to go against the compact design of the PP altogether and have either the battery or Raven dangling to get at the power leads.
I'm only talking in regards to meeting the requirement, I don't see anything in the reg about having to shunt the leads. Maybe Steve can jump in, but if I cut one of the leads to the e-match and leave it open, that alone should satisfy the requirements. I don't need to modify power to the altimeter if the e-match lead is physically open. The reg certainly seems to be an either/or, not both, requirement.


Tony
 
Status
Not open for further replies.
Back
Top