Wiring help with rotary switch, please!

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Mach_Seven

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Not the most challenging question, but this is another first for me. Where do the wires go on this switch? In pic 2, the switch is reversed after I flipped it over, so 3 and 4 are "in", and 1 and 2 are "out". Do they just go straight across? Red "in" to 3, red "out" to 2, and black "in" to 4 and black "out" to 1?
image_50352129.JPGimage_50345985.JPG
 
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Buckeye

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Only one lead from the battery (usually red) goes to the switch and then returns to the altimeter.

1-2, 2-3, or 3-4 can all be used to complete a circuit.

A voltmeter, continuity tester, or just a wiring mockup are all useful for testing out your setup.
 

Worsaer

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I can’t quite tell from the photo. Is that a Schurter rotary switch? You’re likely going to chose to switch only one lead of the battery, often the positive or red lead. Am I understanding your question correctly? if your asking which two lugs on the Schurter switch to use, on one of my old AV bays I switched power using what you show as lugs 1 and 2.
 

Mach_Seven

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Thanks for the help, guys! My soldering iron and accessories will be here today. I'll post the pics and results in the build thread. I'm sure I'll turn that thing into a blob of melted plastic we can all share a laugh over.

Project Phoenix | The Rocketry Forum
 

Mach_Seven

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Only one lead from the battery (usually red) goes to the switch and then returns to the altimeter.

1-2, 2-3, or 3-4 can all be used to complete a circuit.

A voltmeter, continuity tester, or just a wiring mockup are all useful for testing out your setup.
Ah. Good to know. That's two less connections to solder and I don't have to worry about getting the polarity reversed and damaging the altimeter this way.
 

Mach_Seven

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I can’t quite tell from the photo. Is that a Schurter rotary switch? You’re likely going to chose to switch only one lead of the battery, often the positive or red lead. Am I understanding your question correctly? if your asking which two lugs on the Schurter switch to use, on one of my old AV bays I switched power using what you show as lugs 1 and 2.
Then I shall do the same. Thanks!
 

JoePfeiffer

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I use an ohmmeter to make absolutely sure I'm soldering to two leads that are connected by the switch when it's in the "on" position.
 

M Dive

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Try this:
1 = battery +
4 = battery -
2 = altimeter +
3 = altimeter -
Gives you the redundant switch poles suggested by jsdemar, plus a shorting connection on the altimeter power input when in the off (220) position.
 

Mach_Seven

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Really? It's the same as a physical view from the back of the switch. Solder it that way.
Yeah, I kinda knew I'd have to sound like a moron to learn this basic stuff. I'm not an electronics guy. It's a new discipline. But I wasn't a paint and finish guy either, and I've come a long way on that! :cool:

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Learning new skills is the most rewarding part of rocketry for me. On this project alone I'll be soldering for the first time, I've tip-to-tipped the fins with FG for the first time, and created custom water-transfer decals for the first time.
 

Mach_Seven

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Try this:
1 = battery +
4 = battery -
2 = altimeter +
3 = altimeter -
Gives you the redundant switch poles suggested by jsdemar, plus a shorting connection on the altimeter power input when in the off (220) position.
This is what I'm going to do. Then I can also have the battery 9v clip leads attached at the same point, and run them and the wires coming out of the switch forward and long for flight prep.

So 220 is OFF? Does it matter how the switch is oriented in the airframe?
 

DragonRocketry

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Been wiring this way for over 14 years with zero issues. 110 is off, 220 is on.

IMG_1457.jpg
 

M Dive

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Yes, 220 is OFF and 110 is ON if you wire according to the list in my previous post. Others have suggested other hookups that are not the same but will work.

Orientation doesn't matter but I usually orient the switch with the slot vertical (parallel to the airframe axis) when OFF so that when I insert the screwdriver to operate the switch I have an expectation of where to start. I can't always see the switch in the dark hole.
 

Titan II

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Several past threads about this switch. This is a good one. Also, recommend using all four poles as shown in Demar's diagram

 

M Dive

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If your altimeter/flight controller has terminals for a switch, then wire as indicated in jsdemar's post. If it doesn't have switch terminals and you just want to switch power on and off to the device, then wire according to my post (or Scott's post, or Buckeye's post).
 

Mach_Seven

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Yes, 220 is OFF and 110 is ON if you wire according to the list in my previous post. Others have suggested other hookups that are not the same but will work.

Orientation doesn't matter but I usually orient the switch with the slot vertical (parallel to the airframe axis) when OFF so that when I insert the screwdriver to operate the switch I have an expectation of where to start. I can't always see the switch in the dark hole.
Got it. This will be surface mounted to the switchband. Something tells me being in the horizontal position while being exposed to the air stream is less likely to fail. Now I just gotta figure out how to get that nut on the back..
image_67207425.JPG
 

Mach_Seven

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If your altimeter/flight controller has terminals for a switch, then wire as indicated in jsdemar's post. If it doesn't have switch terminals and you just want to switch power on and off to the device, then wire according to my post (or Scott's post, or Buckeye's post).
NOICE! I did it like you suggested in post #12.

image_50374657.JPG
 

M Dive

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Glad you got it working. I use that switch with the Missile Works RRC2 as well. 👍🏼
 

boatgeek

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Got it. This will be surface mounted to the switchband. Something tells me being in the horizontal position while being exposed to the air stream is less likely to fail. Now I just gotta figure out how to get that nut on the back..
View attachment 470044
In the "been there, done that, have the scars" department, I would strongly recommend adding a disconnect plug between your switch and your altimeter. It should be where you can easily reach it to unplug it when taking the sled out of the AV bay. If you slide the sled in and out a lot, the wires tend to pull on those little tabs on the back of the switch and break them off. I got so frustrated that I'll only use those switches hard mounted to the sled so the wire connections never move.

YMMV of course!
 

Mach_Seven

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In the "been there, done that, have the scars" department, I would strongly recommend adding a disconnect plug between your switch and your altimeter. It should be where you can easily reach it to unplug it when taking the sled out of the AV bay. If you slide the sled in and out a lot, the wires tend to pull on those little tabs on the back of the switch and break them off. I got so frustrated that I'll only use those switches hard mounted to the sled so the wire connections never move.

YMMV of course!
Thanks for the advice. I didn't like that either. I will follow your recommendation.
 

SDramstad

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This is what I'm going to do. Then I can also have the battery 9v clip leads attached at the same point, and run them and the wires coming out of the switch forward and long for flight prep.

So 220 is OFF? Does it matter how the switch is oriented in the airframe?
Honestly I would advise against this. It doesnt give you redundancy, It gives you 2 points of failure. If either side opens up you lose power. I would go with jsdemars suggestion. That does give you redundancy. Both would have to fail to give you a problem.
 

Rocketclar

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Another technique I use with those switches is to wrap electrical tape around the base once I secure the backing nut. Reason for this is so that my all threads on the sled don't short out the switch.
 

Rocketclar

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And be careful turning the switch between the two settings. They are easy to break if you go the wrong way.
 
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