Wiring (relays and fuses)

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luxmoggy
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Posts: 21
Joined: Thu Mar 14, 2013 6:08 am

Wiring (relays and fuses)

Post by luxmoggy »

Hello,
I am just buying all the part I need to wire up the engine and MegaSquirt.
I was thinking about using a "Bussmann 15303-6-2-4" so that the relays and fuses for the Megasquirt are all in one place.

The relays are rate 35A... but the largest wire it can take is 12ga which is max 30A... so I can't use the whole 35A.
I know this the the in theory max but I want to be correct. It means changing my wiring a bit to use another relay.

Also is splicing wires the best way to get the one output pin from the relay to go to 4 fuses? or is there better way to do this?
e.g take a length of 12ga and splice some 14/16ga wires to it.

Thanks
Iain

See the post http://www.msextra.com/forums/viewtopic ... 32&t=53534 for my wiring diagram.
luxmoggy
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Re: Wiring (relays and fuses)

Post by luxmoggy »

Hello,
After looking some more and doing more searches. I came across a solution on the WaytekWire website. Don't know why I didn't find them before, I have been looking for this type of solution for months.

The solution is based on a Weather Pack connector range of connectors from Delphi. With a "end cap" and a "BUSS Bar".
It is on page 47 of the WaytekWire catalog under "Sealed Pack Slice System".

You can have up to 6 wires spliced together with this system.

So I will be ordering these parts.
jsmcortina
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Re: Wiring (relays and fuses)

Post by jsmcortina »

Interesting stuff, here's a link to that page http://www.nxtbook.com/nxtbooks/waytek/catalog227/#/46 for anyone else interested.

James
I can repair or upgrade Megasquirts in UK. http://www.jamesmurrayengineering.co.uk

My Success story: http://www.msextra.com/forums/viewtopic ... 04&t=34277
MSEXTRA documentation at: http://www.msextra.com/doc/index.html
New users, please read the "Forum Help Page".
luxmoggy
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Re: Wiring (relays and fuses)

Post by luxmoggy »

Hello,
Can anyone recommend where I can get some 12ga TXL wire for creating this Relay/Fuse panel.

At Waytek I have to buy min 250ft. I think I will only need a couple of ft.

On Ebay I have found people sell 25ft but at more than half the cost of the 250ft.


Thanks for adding the link. It is a Friday, it wasn't until I saw you add it, that my brain kicked in to gear and said "thats a good idea"

2 other questions.
Do you think that these connector would work to turn the 2 injector Earth wires into 3 to go to the injectors.

Has any one used the 560 crimper from Waytek? Is can do 12-20ga.
Two_Wheeler
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Re: Wiring (relays and fuses)

Post by Two_Wheeler »

I know this is an old thread, but I have info that is relevant for future reference.

The 15303-6-2-4 panel is great. I'm using it on my motorcycle in place of the old glass fuse panel. It handles all the needs of the bike plus the added Microsquirt circuits. I was able to use a mating connector and literally plug in the power wiring to the bike (there are only 4 circuits).

There are a number of variations here, so I'll post this in order to help:
Bussmann 15300 reference document
15300 is the panel series.

15303= It mounts with 10-32 screws (popular)
15304= It mounts with 5mm screws (hard to find)

The next number relates to the panel's use and wiring:
1= Fuse/circuit breaker (CB) base, 10 per side
2= Micro relay base, 5 relays plus 10 fuses or CBs
3= Mini relay base, 3 mini or micro relays plus 10 fuses or CBs
4= Non-bussed base
5= Partially bussed base, 5 unbussed relays plus 10 fuses or CBs
6= Partially bussed base, 5 bussed relays plus 10 fuses or CBs

Note: A buss makes wiring circuits fed by the same source much easier.

The next number is the hardware option:
0= No hardware
1= Nuts bulk
2= Nuts assembled
3= End caps bulk
4= End caps assembled
5= Nuts & end caps bulk
6= Nuts & end caps assembled

The last number is the cover option:
0= None
3= Fuse (low) cover
4= Relay (tall) cover- You must use this if you plan to use the micro relays and a cover.

It uses metripack 280 female terminals and round seals. Don't forget to buy blanking seals (Delphi# 12010300) to seal any unused circuits.

As of July 2015, I found a better deal for the panel and two micro relays at a place called Connector Concepts Inc. They were a little less than Waytek on both the panel and micro relays, and shipping was lower. Waytek does not disclose shipping costs until you pay and get an invoice, and they have minimum quantity requirements that make you buy multiple pieces of low-cost items, and will hit you for a $5 small order charge if you are under $35. Comparing my 2012 order CCI was about $3 less than Waytek for shipping. CCI was outrageous on terminals and seals, wanting $22 for a set of 10. You could buy 150 at Waytek for that price, so it pays to shop. There are likely other vendors that would have a better price, I know shipping using two vendors offsets any savings.

As for automotive-grade wire (GXL/SXL/TXL), I found a site called EFI Connection that sells striped wire by the foot with a 10 foot minimum. For TXL, it ranges from 30 to 40 cents from 22 to 18 gauge. Larger wire is of course more. There is a U.S. seller on eBay named brussellex that sells it in 5 foot minimums and will do custom orders.

I'll answer the OP's questions as best I can:
1.
The relays are rate 35A... but the largest wire it can take is 12ga which is max 30A... so I can't use the whole 35A.
I know this the the in theory max but I want to be correct. It means changing my wiring a bit to use another relay.
If your wiring is relatively short, as was my motorcycle, you can use smaller gauge wires. If it has to run a number of feet, then you need to use heavier gauge wire. In your example, using this site's wire gauge table, a 12 gauge wire can carry 41 amps for chassis wiring and 9.3 amps for power wiring. That page also has a handy voltage drop calculator.

2.
Also is splicing wires the best way to get the one output pin from the relay to go to 4 fuses, or is there better way to do this?
e.g. take a length of 12ga and splice some 14/16ga wires to it.
The Sealed Pack Splice System works with a weatherpack 6-way connector. It will not interface with the metripack terminals on the Bussmann panel. It would be fine for a small (1~3 circuit) system.
For splices, I like to crimp & solder an uninsulated barrel splice and cover it with heavy wall heat shrink.
I spliced the output of my main relay to 3 circuits- 2 injectors and Microsquirt power.
I spliced the output of my pump relay to 5 circuits- pump, O2 sensor, and 3 unused circuits for future expansion.

3.
Do you think that these connector would work to turn the 2 injector Earth wires into 3 to go to the injectors?
I'm not sure I understand the question. Most injectors use the Earth (ground) side for triggering, so they must be separate unless you are batch-firing. If you simply need to wire 3 injectors, a splice as mentioned above would work. On my motorcycle, injectors 1-4 and 2-3 are batch fired so I am firing 4 injectors via 2 output wires. If this involves a 3 cylinder engine I do not have any experience with that.

4.
Has any one used the 560 crimper from Waytek? It can do 12-20ga.
No experience with it, but a crimper that has a wide selection of dies is good.
1981 Suzuki GS1000G & 1992 GSX1100G Microsquirt Projects
Adapting fuel injection mostly from a 2003 GSXR600
Hearing "It can't be done" is SOP around here.
Two_Wheeler
Experienced MS/Extra'er
Posts: 159
Joined: Sat Dec 29, 2012 9:40 pm

Re: Wiring (relays and fuses)

Post by Two_Wheeler »

Here are a couple of pictures of my 15303-6-2-4 panel during the install on my motorcycle. The connector in the top photo goes to the original power connector from the old fuseblock. The panel mounted in the same area as the old part via a fabricated panel and relocation of the ignitor box.

Image

Image
1981 Suzuki GS1000G & 1992 GSX1100G Microsquirt Projects
Adapting fuel injection mostly from a 2003 GSXR600
Hearing "It can't be done" is SOP around here.
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