wiring up 3 switches

Dumsterdave

100 W
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May 9, 2016
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copenhagen, Denmark
full disclosure... I know how to solder and understand very basic electronics, but I'm pretty much a novice when it comes to this stuff.

Anyways, I have a 52v battery (em3ev) that I want to run 4 switches from.
Switch 1: Headlight/taillight rated to 60v
Switch 2: GPS tracker (20v) connected by using a 63v buck converter set to 5v
Switch 3: USB charger (63v max input)
Switch 4: nothing for now, but just in case i find something else i need powered on in the future.

So, as of right now I have an xt90s coming off the battery into another xt90s that is split two ways (xt90s on one end and xt60 on the other). from the xt60 is where I will have my switches coming from. Right now I wired up some temporary switches using jst connectors and cheap on/off rockers, and they work, but im not sure if they wired in right.I am not using any fuses at the moment. Does anyone have time to draw up a real quick wiring diagram. Honestly it doesn't have to be much, but I just want to make sure Im not going to start any fires. Should i have some fuses somewhere in the wiring? Is it ok to have the buck converter on 100% of the time? I would assume it will always be draining the battery a little bit, but also i doubt if it'll be much.

Thanks for the help
Dave
 
ATTACH]
 
and the switches say 3A at 250v AC or 6A at 125v AC

Im also wondering if i shouldve wired the positive and negative the opposite of what I currently have.. So, positive to the switch and negative to the light or does it really matter?
 
Not sure where the XT60 is located, but I'd advise minimizing the number of battery voltage wires running to the handlebars, especially if you aren't fusing. In other words, locate the XT60 at the bars and branch out from there.

You can add a fuse where it branches from the XT90 to protect the circuit going to the bars.
 
E-HP said:
Not sure where the XT60 is located, but I'd advise minimizing the number of battery voltage wires running to the handlebars, especially if you aren't fusing. In other words, locate the XT60 at the bars and branch out from there.

You can add a fuse where it branches from the XT90 to protect the circuit going to the bars.

The xt60 is located in the homemade battery box in the bikes triangle. It makes sense to have shorter wires going to the switches, but I also the GPS tracker in the box so I would have to run wires back from the handlebars to the box in order to power that. Right now it is connected to an rf switch that is not on the bike (that way someone can't just flip the switch and turn off the gps
 
You should not need much current for the accessories. What about a small single or double sided PCB mounted to your battery box with 5mm fasteners? Then solder battery power cables (10 or 12 AWG) to the pins for the XT90S.
XT90-60F PCB (1024).jpg
Conventional wisdom says the battery connectors should be female. The XT90S is a female connector so make the XT60 connectors female as well.

If any accessories need wires 'inside' the battery box then you can connect them (16 or 18 AWG) to one of the XT60 pin sets (negative to negative and positive to positive).

If any accessories need a switch then simply put a SPST switch inline with its power cable (either positive or negative side will suffice). I feel lights should be on any time power is on, but I am just being picky ... end of public service announcement.
 

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LewTwo said:
You should not need much current for the accessories. What about a small single or double sided PCB mounted to your battery box with 5mm fasteners? Then solder battery power cables (10 or 12 AWG) to the pins for the XT90S.
XT90-60F PCB (1024).jpg
Conventional wisdom says the battery connectors should be female. The XT90S is a female connector so make the XT60 connectors female as well.

If any accessories need wires 'inside' the battery box then you can connect them (16 or 18 AWG) to one of the XT60 pin sets (negative to negative and positive to positive).

If any accessories need a switch then simply put a SPST switch inline with its power cable (either positive or negative side will suffice). I feel lights should be on any time power is on, but I am just being picky ... end of public service announcement.

i seriously considered your idea about putting the splitter at the handlebars, but I already have long cables for the USB, horn and front/rear lights. so I think ill keep the splitter in the triangle. Also the GPS is located in the triangle as well so keeping the splitter there keeps me from running wires out to the handlebars and back just to power that. I guess I could have another splitter hiding in the triangle, but there are already plenty of wires, connectors and a GPS unit in there. This is my latest attempt. (I actually forgot to draw on one more xt90-s after the other xt90-s... so xt90-s split to another xt90-s AND the xt60 in the drawing I hope that makes sense) How does it look?
167135761_479786230103217_3822934582978044440_n.jpg
 
The RF switch has a "+ in" "- in" and "+ out" "- out"
Same for the buck converter. The GPS runs on 12v that is why I have the buck
am I right in wiring it like I have drawn?
 
E-HP said:
Not sure where the XT60 is located, but I'd advise minimizing the number of battery voltage wires running to the handlebars, especially if you aren't fusing. In other words, locate the XT60 at the bars and branch out from there.

You can add a fuse where it branches from the XT90 to protect the circuit going to the bars.

the xt60 is located in the triangle of the bike and I have 20awg wires running to the handlebars. I put a fuse on the positive before the xt60 and made a new wiring harness. I decided to keep everything in the triangle because I already have long cables running from the accessories and plus the rear light and rear leds would have extra long cables if they needed to be ran all the way to the front handlebars.... and I have an RF switch inside the triangle and that would require me running wires out to the handlebars and back to power it (plus it runs the risk of being cut by a thief and disabling the GPS). I have updates my drawing... check it out and tell me what you think
 
Dumsterdave said:
the xt60 is located in the triangle of the bike and I have 20awg wires running to the handlebars. I put a fuse on the positive before the xt60 and made a new wiring harness. I decided to keep everything in the triangle because I already have long cables running from the accessories and plus the rear light and rear leds would have extra long cables if they needed to be ran all the way to the front handlebars.... and I have an RF switch inside the triangle and that would require me running wires out to the handlebars and back to power it (plus it runs the risk of being cut by a thief and disabling the GPS). I have updates my drawing... check it out and tell me what you think

Electrically it works. When I mentioned minimizing the battery voltage wires, one way to do that by running only one set of wires to the front with battery voltage, 2-conductor cable with decent jacketing. https://www.wireandcableyourway.com/16-2c-thhn-pvc-tray-cable?utm_source=google&utm_medium=cpc&utm_campaign=shopping&gclid=Cj0KCQjwmIuDBhDXARIsAFITC_6W59fJPuEY0lLs8-zQCEIn79PmVMhNusP2KnH2Zth8HgN4pYuVg3saAsgYEALw_wcB

Add a terminal block/bus up front for branch circuits where the device is also located up front. https://www.google.com/search?q=terminal+block+&tbm=isch&ved=2ahUKEwiS47Lhv9nvAhWyIjQIHb6cB_kQ2-cCegQIABAA&oq=terminal+block+&gs_lcp=CgNpbWcQAzIECCMQJzICCAAyAggAMgIIADICCAAyAggAMgIIADICCAAyAggAMgIIAFC9mQxY7JoMYJudDGgBcAB4AIABR4gBR5IBATGYAQCgAQGqAQtnd3Mtd2l6LWltZ8ABAQ&sclient=img&ei=OeBjYNLiO7LF0PEPvrmeyA8&bih=760&biw=1536&rlz=1C1CHBF_enUS922US922 If you already have the XT60 wired up with branches, you could just relocate it to the front, instead of adding a bus.

For devices located at the rear of the bike, switch via the negative/ground, so that you only run a thinner switched ground wire to the device. You'll need to split the battery positive, after the fuse, out back, for powering the rear located devices.
 
Dumsterdave said:
167135761_479786230103217_3822934582978044440_n.jpg
After the XT60, why break out to connectors and then recombine the red positive into one wire? Kinda defeats the purpose of the connectors since you can't disconnect anything individually.

Also, most properly, you'd need to fuse for each breakout wire individually. Your 10A fuse before the XT60 protects only that wire and connector. If your 20AWG is only good for 5A and your only 10A fuse is before the XT60, then if any individual breakout wire carries more than 5A but less than 10A, it will burn up. This doesn't have to be complicated or expensive -- I just directly solder wires to the legs of cheap automotive fuses and heatshrink over them.

Since JSTs aren't rated for this use anyway, I'd just hardwire everything that you're not regularly removing.
 
fatty said:
Dumsterdave said:
167135761_479786230103217_3822934582978044440_n.jpg
After the XT60, why break out to connectors and then recombine the red positive into one wire? Kinda defeats the purpose of the connectors since you can't disconnect anything individually.

Also, most properly, you'd need to fuse for each breakout wire individually. Your 10A fuse before the XT60 protects only that wire and connector. If your 20AWG is only good for 5A and your only 10A fuse is before the XT60, then if any individual breakout wire carries more than 5A but less than 10A, it will burn up. This doesn't have to be complicated or expensive -- I just directly solder wires to the legs of cheap automotive fuses and heatshrink over them.

Since JSTs aren't rated for this use anyway, I'd just hardwire everything that you're not regularly removing.

Yeah, I guess thats another thing I didn't make clear. Each jst in the picture is split into a total of 3 jst's.
So everything is removable... The switch and the accessories can both be unplugged. The reason all the positives come together into 1 wire is because I only had a 5 wire cable.So I had to solder short bits of wire between the positives of each switch. For the other end (jst side) I spliced in 3 more wires into the positive and soldered it. Honestly, I have no idea if this makes sense Untitled2_20210331071653.png
 
Kinda, but why JSTs in the first place? "I had to solder short bits of wire" sounds like many points of failure for parts that aren't meant to be removed. It's not like your light will still work if you remove the switch...
 
fatty said:
Kinda, but why JSTs in the first place? "I had to solder short bits of wire" sounds like many points of failure for parts that aren't meant to be removed. It's not like your light will still work if you remove the switch...

I'm my observation, crimped JST plugs are more reliable than soldered joints. That's apart from them being much easier to service when things go awry.
 
fatty said:
After the XT60, why break out to connectors and then recombine the red positive into one wire? Kinda defeats the purpose of the connectors since you can't disconnect anything individually.

Also, most properly, you'd need to fuse for each breakout wire individually. Your 10A fuse before the XT60 protects only that wire and connector. If your 20AWG is only good for 5A and your only 10A fuse is before the XT60, then if any individual breakout wire carries more than 5A but less than 10A, it will burn up. This doesn't have to be complicated or expensive -- I just directly solder wires to the legs of cheap automotive fuses and heatshrink over them.
Since JSTs aren't rated for this use anyway, I'd just hardwire everything that you're not regularly removing.
[/quote] this is what I mean, everything can be disconnected, but the wires will have to remain. But the more I think about it, I am now worried that the single 20awg wire may not be thick enough. This is all somewhat temporary
Untitled3_20210331074550.png
 
Chalo said:
I'm my observation, crimped JST plugs are more reliable than soldered joints.
Then something is very wrong with the soldered joints you're seeing.
 
fatty said:
Chalo said:
I'm my observation, crimped JST plugs are more reliable than soldered joints.
Then something is very wrong with the soldered joints you're seeing.

How do you reckon? Crimped connections don't stiffen the wires they attach to and promote breakage. You can't make a "cold" crimp. It won't fail to wet.

Mass producers don't solder harness wires; they crimp them always. Is this because they're trying to put six sigma consistency in jeopardy?
 
Dumsterdave said:
This is all somewhat temporary
Untitled3_20210331074550.png
Hopefully -- none of this makes much sense. None of it is removable and you have switches for disconnecting loads, so you don't need extra connectors. Just run a single larger 2-conductor cable (rated for the sum of max loads for all devices) from the XT60 to your switch location (handlebars?) and then split out to smaller 2-conductor cables (rated for the max load of only the connected device) to each switch.

Cable is cheap enough to do right. The 20/2 cable I use is rated at 5.6A, and protected by 5A auto fuse.
 
Chalo said:
How do you reckon? Crimped connections don't stiffen the wires they attach to and promote breakage. You can't make a "cold" crimp. It won't fail to wet.
As I said, these all fall under "very wrong". There are just as many ways to incorrectly crimp terminals.

Chalo said:
Mass producers don't solder harness wires; they crimp them always. Is this because they're trying to put six sigma consistency in jeopardy?
Soldered or crimped connections can both be done right, and can both be done wrong. See IPC J-STD-001ES.

The debate isn't between soldered or crimped terminals. The debate is between soldered or JST connectors. Real Japanese JST-XH is rated at 3A but he's probably got loose Chinese eBay knockoffs, they don't even have cycle life ratings (because they're for internal PCB connections), and they don't lock. To say they're more reliable than properly soldered connections is completely wrong.
 
fatty said:
Dumsterdave said:
This is all somewhat temporary
Untitled3_20210331074550.png
Hopefully -- none of this makes much sense. None of it is removable and you have switches for disconnecting loads, so you don't need extra connectors. Just run a single larger 2-conductor cable (rated for the sum of max loads for all devices) from the XT60 to your switch location (handlebars?) and then split out to smaller 2-conductor cables (rated for the max load of only the connected device) to each switch.

Cable is cheap enough to do right. The 20/2 cable I use is rated at 5.6A, and protected by 5A auto fuse.

Maybe my drawings are bad so here is a photo of one my my olda switches. The pos and neg are wrong, but other than that everything is connected the same way now (just longer wires). I used all the connectors to make it so that everything is removable. IMG_20210331_105604.jpg
 
ok, bit of an update.
I decided to take the advice of running a single power cable up to the handbars and splitting from there. I then shortened all the accessories (headlight, USB, horn) and then rewired all 4 switches with individual + and - wires and terminated them with jst connectors, which were then ran to the power cable cluster area (not sure how popular this is, but I want to be able to disconnect everything because I will soon be purchasing a new switch cluster and I may get new accessories and its easier to just unplug and plug a new on in).

Now the smaller wires are short and they are fused by a 5A fuse. I also split from the xt60 inside the box with 20AWG wires to make 2 more connections. One is for the GPS/buck converter (controlled by an RF switch) and the other is for nothing right now. They are also fused with a 5A fuse. my handlebars are still cluttered (maybe even a bit more than before since all the connections are done underneath a velcro cover instead of inside the battery box). Now I want to do something about my CAv3. the 6 wires coming from the back are a bit of an eyesore. I could get rid of the display altogether an just run directly from my phaserunner, but I like the idea of having a display.
 
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