Help! Any electrics experts out there?

Humbug

Humbug

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I bought one of these heated jacket kits a while ago but never got round to fitting it. http://www.heat4jackets.com/

As it was getting bloody cold the other night and I had to make an early start to Dorchester and then Poole I got my nearest and dearest to finally sew it it for me.

Duly hooked up I tried it on the bike statically - it seemed to get warm but not that warm.

Set off the next morning, over the top out of Crewekerne the temperature was reading -5C!!! Jacket didn't feel much warmer than usual and I was glad of the heated grips.

I thought the Canbus may be tripping the auxilliary socket but when I got to CW's they loaned me a R850R and I plugged it into that for the trip to Poole. This made me realise that the GS screen does give surprisingly good protection as on the naked demo bike I was f*ckin' freezing!

I got back home and checked all the connections - they seemed okay but to be on the safe side I soldered them all. Tried it again but it was no better. I hooked a 12v charger to it and wrapped some of the heating element around a temperature probe and got a maximum reading of 37C - which is not that warm - certainly not the very hot the instructions tell you the wire will get! I could put it in my mouth with no risk of burning!

The length of wire has been checked and this is the recommended 33 ft.

I removed the long, thicker guage attachment cable and attached the 12v source direct to the heating element/wire. It ran no hotter. I placed a voltage meter across the power source, unconnected to the heating element and got a reading of about 13.5v with no load but with the element connected, the voltage drops to around 9v with a load of just under 4 amps.

I have emailed to seller and he has not come across this before and has been very helpful so far and has even offered me a full refund including postage costs. I don't really want that as I want the heater kit to work!

Could there be a problem with the element wire causing this voltage drop? I am no expert of electronics so any advice would be much appreciated.

Andy
 
If the element is drawing 4Amps that would be about 50 watts at 12 volts, I suggest you check with your supplier that that is about right, it sounds plausible. If that is as it should be, the the fault lies with supply to your jacket, possibly in a high resistance in the bike wiring somewhere. Just as a benchmark the human body put out about 100-150 watts in idle mode so just 50 watts extra should make a difference especially if it's on the inside of any inslation you're wearing.

Mind you, -5c added to wind chill is f.. cold !!!
 
50 watts would be about right because it's supposed to be rated at 55 watts. However, when I connect any 12v+ supply the voltage drops by approx 25%. I'm confused, surely the voltage should not drop. Don't forget, I have hooked up 3 seperate 12v supplies to this and they all drop the voltage.??????? :confused: :confused: :confused: :confused: :confused: :confused:
 
jedi-knight said:
50 watts is about right. I think these elements are rated at 55w.

Does anything else in the connection line get hot at all - plug, soldered wires etc?
Click to expand...

I've taken the plug out of the equation by connecting the supply directly to the heating wire/element but it makes no difference.
 
themadprofessor said:
I'd say that all your power supplies are not man enough to run the current!!
Click to expand...

So is it just a coincidence that a R1200GS, a R850R and a 4amp hour 12v battery charger can't power this kit????
 
I wouldn't be surprised that a battery charger can't supply 4 amps, most trickle chargers supply less than an amp, for example 0.6A for an Optimate.

I'd try connecting the jacket directly to the bike's battery (well charged), with the battery removed from the bike. If the battery voltage drops to 9V when you are drawing 4A, the battery is knackered. At a guess, a lead acid battery of that size should be able to supply at least 20A without dropping below 12V.
 
You say that you have measured a current of 4A at 9V, so the element resistance would appear to be 2.25ohms.

At 9V, you are getting 36W, if you connect 12V across 2.25ohms, you will get 5.33A flowing, and 64W. Almost twice the power.

Question is, do you have a battery capable of delivering 5.33A at 12V?
 
shugie said:
You say that you have measured a current of 4A at 9V, so the element resistance would appear to be 2.25ohms.

At 9V, you are getting 36W, if you connect 12V across 2.25ohms, you will get 5.33A flowing, and 64W. Almost twice the power.

Question is, do you have a battery capable of delivering 5.33A at 12V?
Click to expand...

This morning I connected to my car battery which is rated at 66A/Hr and got exactly the same result - so 3 batteries in tip top condition and one charger gets the same result. Oh, and I also wired it direct to my VFR's battery which is on an Optimate and also got the same result. So although most folk seem to be telling me my power source is wrong the only thing that has been constant in this experiment is the heating wire. Surely, it must be faulty?
 
Humbug said:
This morning I connected to my car battery which is rated at 66A/Hr and got exactly the same result - so 3 batteries in tip top condition and one charger gets the same result. Oh, and I also wired it direct to my VFR's battery which is on an Optimate and also got the same result. So although most folk seem to be telling me my power source is wrong the only thing that has been constant in this experiment is the heating wire. Surely, it must be faulty?
Click to expand...

Did you connect the heating wire directly across the car battery, and if so, what was the current then? I assume that the battery voltage remained at 12V.

Also, if you have a multimeter than can measure resistance, why not connect across the ends of the heating wire and measure the resistance?

The website says the kit is intended to produce 55W, so the resistance needs to be something like 2.6 ohms - be warned that some multimeters will not always measure resistances this low accurately.
 
Hi Shugie,

I'm getting out of my depth here and do not really understand all this stuff very well. I have tried to eliminate the power supplies here and have managed to change everything except the wire itself which does appear to be the culprit - but who am I to say?

Below is what I have written to the seller of the kit who has been very fair all along but obviously refuses to replace the wire or accept is it at fault.

I'll need the refund though because it seems that I'll now need to buy 2 new bike batteries, one new car battery and a new battery charger!

One funny thing is that both bikes are fitted with heated grips and these work just fine - don't they put out a similar amount of heat or even higher?

Andy

Hi Richard,

It seems that I will have no option but to return the kit.

This I sadly do not really want to do but it seems I have no choice.

Although you disagree with me you have offered no explanation as to why 4 batteries and one very powerful charger cannot get this wire hot. If all these power supplies were faulty none of my bikes would start, my car would not start and my battery charger would not recharge batteries. All I know is that if I connect my charger direct to the heating wire the voltage output drops from 12+v to 9v and the charge rate on the charger shows 4amps. Four perfectly good batteries also give the same result. The one fitted to my BMW is only 5 months old and the bike is used regularly. the one fitted to my Honda is less than 1 year old and is kept connected to an Optimate when not in use. My car is also used almost daily for fairly long journeys (160 miles today). The R850R was CW Motorcycles of Dorchester's demo bike and was less than 1 year old and is demonstrated regularly. I cannot believe they would not keep their battery in tip top condition. Incidentally, with the bikes and car engines running it made no difference whatsoever so are all my alternators faulty too?

As I have said I am not an electronics expert but it seems to me the only thing I have failed to eliminate is the wire itself. Have you considered that?

If you are not prepared to replace the element then please supply your full name and address and I will return the items for a full refund as you have kindly offered. I can assure you that the length of wire is as it was received (less the small amount I have had to cut off to remove the crimp connectors).

Regards,

Andy
 
I think the problem lies elsewhere.

Specifically - at what position do you place the electric vest?

I ware a shirt/T-shirt next to my skin then the electric vest, then a thermal jacket them the motorcycle jacket. This way the heat is closest to me,

If you ware the vest towards the outside then the heat goes mostly outwards. You won't get as much benifit from the heat.

------------------
50 watts is about right. The drop from 12 volts to 9 volts means the supply is being loaded, not a problem for the electric vest. Could be a problem with the supply - battery dropping? Lead and or fuse resistance dropping the voltage?
 
I made up my own jacket using one of these kits, and as frank says, keep it as near to your body core as possible.
I put mine in a lined fleece top, and i have to wear long sleeve T shirt underneth, otherwise the tiny areas ( couple mm) where the wire is exposed, burns the skin. The wire is only exposed because youjust nick it through the material to hold it to get the shape you want.
When i wear something tighter over the top of the heated fleece, it feels very warm, as the heated elements are pressed against you.
I have mine running through an adjustable thermostat, so i can be as hot or warm to suit the weather.
 
Humbug - did you find a resolution to this issue? I've experienced exactly the same as yourself with the kit.

When I very first plugged it in to test, it seemed to get nice and toasty. Now it just gets sort of warm.

Pulled it all apart and connected the two element wires directly to a good condition 12v battery. Same result. Bit of a bugga really in this c-c-c-c-c-cold weather.
 
jedi-knight said:
Humbug - did you find a resolution to this issue? I've experienced exactly the same as yourself with the kit.

When I very first plugged it in to test, it seemed to get nice and toasty. Now it just gets sort of warm.

Pulled it all apart and connected the two element wires directly to a good condition 12v battery. Same result. Bit of a bugga really in this c-c-c-c-c-cold weather.
Click to expand...

Hi,

The chap who sold the kit has been really helpful and has promised to send me a new length of wire from a fresh roll so I can evaluate that. I really hope it works as I don't appear to have any avenues left to explore! The concept of this kit is excellent and I really want it to work.

I'll let you know as soon as I've tested the new wire.

Andy
 
Thanks Andy - I have contacted Richard and asked for his views. It's very co-incidental that we both have the same problem. Like yourself, I want this to work!!!

Interestingly - I had soldered the element to the flylead and it sounds like you did as well. I can't think that soldering would bugger it up but ........

Regards,
Rich
 
Hi Rich,

I have now received the new length of wire from Richard, have placed it straight across the battery terminals and am pleased to report that it works perfectly.

So I would like to say many, many thanks to Richard for all his help, patience and understanding in this matter. :thumb :thumb :thumb

A top piece of kit and I shall certainly be buying more for my long suffering pillion and can now wholeheartedly recommend it to all my friends!

Andy
 
Nippy Normans supply Touratech, Wunderlich, Desert Fox and many other makes of accessories.
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