Recommended wire gauge for Level 2 launch controller

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Nilo

Well-Known Member
TRF Supporter
Hello Nilo,

I certainly am the Wilson of Wilson F/X. My cousin Dan Fox is the F/X just in case you were wondering.

As for a PBU-1w, it certainly would fill all your single rocket launch needs, but only as far as the pad end of the launch system. Its only half of a Wilson F/X launch system. You'd also need a controller. The LCU-1w and the PBU-1w together are a single-pad wireless launch system. Works out to 5000 feet. You'll need a separate 12v battery to go with each end of the system.

Any questions?

I went to your website and found the prices for a wired LCU-1/PBU-1 combo
for $260 and the wireless combo units for$560. I'm assuming both , the wired and the wireless, offer continuity test at the controller end. I'll probably buy your wired combo units for now.

Not only do you have excellent products, but your helpfulness and service is the best.

As a side note Pratt Hobbies responded to my email, and the instructions for their relay doesn't allow for continuity at the contoller's end, just by the relay side.

Thanks again.

Nilo

Nilo

Well-Known Member
TRF Supporter
I built a launch controller last year that is 2 piece. The battery (12v gel cell for a UPS) and electronics sit close by the launch pad. I used automotive relays that are electronically tripped. I used Cat5e to run from the battery box to the hand controller. I can check continuity at both the battery box & the hand controller. With a system like this you don't need long lengths of heavy wire. I have maybe 10' of heavy wire running from the battery box to the ignitor clips. I used this thread to build it.

And I highly recommend using wire with a silicone jacket. It is much more flexible that other wire (helps with the tight wiring inside the battery/electronics box) and it stays flexible in the cold.View attachment 445624View attachment 445625View attachment 445626

Greg:

Thanks for your reply. Your design would definitely solve my needs, but I'm not that electronics savvy to tackle such construction.

Nilo

Nilo

Well-Known Member
TRF Supporter
Hello Nilo,

I certainly am the Wilson of Wilson F/X. My cousin Dan Fox is the F/X just in case you were wondering.

As for a PBU-1w, it certainly would fill all your single rocket launch needs, but only as far as the pad end of the launch system. Its only half of a Wilson F/X launch system. You'd also need a controller. The LCU-1w and the PBU-1w together are a single-pad wireless launch system. Works out to 5000 feet. You'll need a separate 12v battery to go with each end of the system.

Any questions?

I went to your website and the LCU-1/PBU-1 for $260 could satisfy my needs. I'm assuming you could check continuity at the controller end ? How can I place an order? I couldn't find an option to do it on the website, or a phone number to place an order. You are definitely a great asset to the rocketry community. Excellent products, service, and caring for your customers and fellow rocketeers. Nilo Nilo Well-Known Member TRF Supporter I think the least expensive way is using a relay. You don't have to build anything. 12 volt relay modules are available and this system would only require a separate battery at the pad and the wire to complete. This module uses a low voltage input to activate the relay. You can use 22 ga alarm type wire to over 500 ft if you want. Relay Module One Way 30A Optocoupler Isolation Relay Module High Power Relay High/Low Level Trigger YYG-2(12VDC) Available at Amazon:$11.19View attachment 445602
How do you wire it to get continuity test at the controller?

Nilo

Well-Known Member
TRF Supporter
I have often used 13 AWG twin flex speaker cable over 200' powered by a 12V / 7Ah SLA battery with no problems. However, this represents ~1 Ohm resistance for the return length, plus ~1.5 Ohm for the igniter. You are dropping ~5V over the cable and limiting your ignition current to ~4.5A. While this is still sufficient to fire your igniter, it is very inefficient. As others have suggested, a relay based system it the logical choice for high power launches where your standoff distances are from 100' (200' for complex) and upwards.

To directly answer your questions though, 12 AWG @ 300' is ~1 Ohm return, and 14 AWG @ 300' is ~1.5 Ohm return. So, yes, 12 AWG is better, but that's still a heavy pile of cable to carry around and probably expensive. As suggested above, using 3-core extension cords is an economical idea, as you can parallel two of the conductors to halve the resistance of one of the lines to the pad.

As this is your entry to high power, the suggestion to achieve this through an established club is good advice.
Thanks for answering my question about the gauge size of the wire. The launch controller that I built is designed for up to 50', sans a relay.

RocketRev

And yes, you get a continuity report at both the pad-box as well as at the controller.

sghioto

Well-Known Member
How do you wire it to get continuity test at the controller?

If you use a super bright 5mm white LED they are visible at 300 Ft.

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sghioto

Well-Known Member
Right now I have a system for 50' length
Just curious what brand or model is your launcher?

Nilo

Well-Known Member
TRF Supporter
This is my launch controller that I built. I tested it with a UPS battery, as well as a car battery. The car battery worked better- faster igniting.

I'm also including the schematic.

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sghioto

Well-Known Member
That's a nice looking unit.
Kind of surprised you didn't want to expand it with the relay option.
Would definitely save some money.

jrap330

Retired Engineer, NAR # 76940
TRF Supporter
Yes very nice and you are going with a long run of cable...made a Spool stand....fantastic job.

prfesser

I went to your website and the LCU-1/PBU-1 for \$260 could satisfy my needs. I'm assuming you could check continuity at the controller end ?

How can I place an order? I couldn't find an option to do it on the website, or a phone number to place an order.

You are definitely a great asset to the rocketry community. Excellent products, service, and caring for your customers and fellow rocketeers.

Nilo
I will echo the quality of Wilson F/X products and the service provided by The Rocket Rev. The wireless system we bought last year is beautifully made and has worked flawlessly. Well, except for the ID 10T error I made the first time we set up. It helps to READ THE INSTRUCTIONS TERRY!

It is wonderful not having to unwind/wind 200+ feet of heavy multiconductor cable!

Best -- Terry