Topic: Complete Relay Wiring Diagram

[USA-C5-Owner]

I finally get to start the wiring this weekend  .    The wiring diagram I have drawn is pasted below for reference.  If anyone sees anything to be added or changed, let me know.

[KarlG]

Hi,

I find your circuit to be a bit over engineered. My conclusions are based on the original C5 configuration.

Some of the fuses are highly overrated, 15A for the turn indicators, and 20A for the lighting. Assuming you are using the original lighting system, the front and rear bulbs are rated at 5W each i.e. 10 watts total, 10 watts constitutes .83A. So a 2A sloblo fuse is sufficient. I don't know what the rating is for the turn indicators as I use LEDs, but it should be around about the same as the lights. I also don't know what gauge wire you are using for your lights and indicators, but I can imagine the fire brigade being call out if you have a short circuit

Why are you using two flasher units when one will suffice? Look at the circuit below.

http://i1077.photobucket.com/albums/w477/XE521/Example_zps5a46960c.jpg

But on the other hand, if you are happy with the system that all that matters.

[USA-C5-Owner]

Karl, Thanks for the suggestions.  I ended up using one flasher relay in the order you had shown and it worked fine.  I will also adjust the fuse panel to small amp circuits as well.  Thanks for the suggestions, the input really helps.   

[USA-C5-Owner]

I did take in account the fuse suggestions and and flasher suggestion by Karl.  Thank you again.  After wiring the C5, everything works fine.  The diagram is not perfect, but may be a good start to someone needing a complete rewire from a badly abused C5 like mine.

I ran everything in wire loom tubing, and just a note for someone else, it can get tight near the back frame and near the chain depending on how you run the wires.

Regards

[jockywilson11]

Your Motor fuse is a bit small. I monitor mine on the move, and the starting current can be as high as 90amps. You might want to consider a 100a fuse if you are fitting one. Stall current on the Motor is 140a so it should be ok. Going up hill whilst pedalling 40a is a fairly typical figure.

I also kept the original thermal switch in series with the Motor switch on mine to trip the motor if it gets hot. To keep the motor cool I also fitted a 12v computer fan on the end of motor. Mine runs all the time, but some folks wire them to run with the motor when it runs.

Cheers Jocky

[KarlG]

Hi Adam,

as jocky pointed out the thermal cutout switch on the motor body should be fitted, with your experience I don't need to tell you what happens if the motor bady overheats. 

I fitted a thermal controller to the fan, as there's no point in wasting power to cool a cold motor, and it's connected into to the main switched 12v circuit. Dan's fan mounter mod is also a very good investment.

Anyway, av phun.

Karl.

[jockywilson11]

Hi Karl,

one of these? I would be considering a NO version, so it switches on when it gets hot. what temp would you suggest?

http://www.ebay.co.uk/itm/KSD9700-Temperature-Switch-Thermostat-Thermal-Protectors-Normally-Open-Closed-/171544735226?pt=LH_DefaultDomain_3&var=&hash=item27f0dcedfa

[KarlG]

Hi Jocky,

looks like an interesting unit, I might give it a try.

Mine was stripped out of an old computer, and to tell you the truth it was about 10 years ago and I can't remember at what temp. it was triggered. The one I was using was proportional as apposed to on/off. I will be conducting test as soon as all the mods have been introduced, so I prefer a unit that I can adjust according to my findings. Up till now I haven't measured the temp. that a motor can reach when heavily loaded, it's something I try to avoid. 

Sorry, but If I gave you a figure it would be a guess, so I'll refrain. Hopefully someone who has had experience can supply some information.

[jockywilson11]

Fair Comment.

I like to keep things simple, I find electronics on the C5 don't do well - probably due to the poor state of the roads round here, too much vibration on a vehicle with no suspension to speak of is probably the route cause - lol.

I saw on C5 Owners that the temp recorded was averaging between 25 and 32deg C so I think I'll go with the 25deg C one and see how that goes.  http://www.*c5alive is the best*/sinclair-c5-projects.aspx at least that way it will kick in when the temp in the summer is higher :-)

Cheers John

[KarlG]

Hi John,

at first I thought you had selected a somewhat low temerature, but after going through my notes I did find data that I'd forgotten about. At first I had a higher temperature lodged in my mind, but this was the C5 CB cutoff temperature. The figures I have are about the same as you quoted.

How do you intend to mount the switch? I used some leftover heat conducting tape intended for mounting heatsinks onto the computer CPU.

I'll will still use the old unit so I can experiment with the settings, but I think I'll go for your selection for the other C5s.

Have you improved the exit airflow problem, if yes what have you done? Even though there are no hills in the immediate vicinity, I need to watch out, as I intend to couple up a trailer.

Av phun.   Karl.

[jockywilson11]

Hi Karl,

I've not solved the airflow problem, but I was planning on just using epoxy resin to glue it to the case next to the existing cut out switch that's held on with the steel clip.

I can't see why your method won't work, I don't have any of that tape to experiment with it.

I'll post a picture when I've fitted it, ( Still waiting on it arriving).

Cheers John

[KarlG]

Hi John,

I wouldn't advise the use of epoxy resin, although it's not a good heat insulator it will still work as one. There is heat conductive adhesive on the market, and of course heat conductive tape. The tape would be cheaper, but I must admit it wasn't the best solution due to the curvature of the motor body. You should find it at any good computer shop, the IN, even ebay.

http://www.ebay.co.uk/itm/Super-Thermal-Conductive-Adhesive-Paste-CPU-Heat-Sink-Diodes-195-1-5gm-/161473085749?pt=LH_DefaultDomain_0&hash=item25988bc135

Adhesive also has it's disadvantages, e.g. in the removal of the motor, unless you fit a connector to the switch leads and don't solder it inline. The original thermal switch and thermistor are not permanetly fixed to the motor.

[jockywilson11]

http://www.ebay.co.uk/itm/SPEED-FASTENERS-FOR-S-TAP-SCREW-SIZE-6-8-10-12-14-U-Nuts-Spire-Nut-Clip-Auto/141613921538?_trksid=p2047675.c100005.m1851&_trkparms=aid%3D222007%26algo%3DSIC.MBE%26ao%3D1%26asc%3D29952%26meid%3D2c8c28eb328e4e42aef645ab6c33f4e3%26pid%3D100005%26rk%3D2%26rkt%3D6%26sd%3D381138892951&rt=nc

I'll use one of these and some of the thermal grease I have in the house from a PC build, that glue is pretty expensive... 60 quid for delivery!

[KarlG]

Hi John,

I can only say oooooooops, I didn't notice the delivery price. I've got some here that I bought some time back, but please don't ask me were it is.

Anyway best of luck with mounting the switch.

Av phun.

Karl.