[OZAPRS] set up ford territory

[Peter Bye]

Very valid points Michael, and admittedly this is something that I had 
not considered.  However in saying that...
As I mentioned, I utilise Rig Runners to power my kit, I use the smaller 
5 way 40amp unit.  The main power feed is always fused, both +ve and 
-ve, and with a 50amp fuse.
I also am very meticulous with my wiring and power set ups etc (comes 
with the trade, just can't uncle jims workshop and aircraft :-0  )
I am about to fit out my latest vehicle, a 92 Hilux.   I have looked at 
yours with great interest, as there isn't a great deal of variation in 
the interior design...

Thanks

Pete VK2MPJ

On 27/05/12 17:13, Michael Carey wrote:
> Hi Pete,
>
> If you have a fuse on the negative wire then you will be "fairly" 
> safe.  You have to make sure that there is no possibility that your 
> radio power cable, radio and antenna coax can ever take the full 
> "earth" current of the vehicle.
>
> If for any reason the negative battery strap became disconnected from 
> the body/chassis/engine block then there is a possibility that your 
> radio will provide the necessary path... and I'm sure it wouldn't 
> survive the demands of a modern vehicle.  For instance on the new Ford 
> utes there is only ONE wire going from the negative terminal to the 
> body of the vehicle.
>
> I had a situation with a SES rescue 4WD where the battery was isolated 
> (when the 4WD wasn't being used) with a HUGE disconnecting switch and 
> HUGE cable.  This was done on the negative side of the battery... it's 
> perfectly fine to do this.
>
> BUT, the Codan HF radio negative had been wired directly wired to the 
> battery WITHOUT a fuse... thus bypassing the isolating switch!
>
> The HF radio was not earthed at this stage as the HF antenna was 
> incorrectly installed (the reason I was looking at the vehicle), the 
> rubber mounted Codan antenna wasn't connected to the chassis, only the 
> mounting bracket was... the factory fitted copper braid wasn't 
> present.  When I connected the earth properly to the Codan antenna, 
> the WHOLE vehicle came to life, I had completed a circuit by 
> connecting the earth to the chassis. A very big spark ensued and I 
> quickly disconnected the earth to see what was going on... this was 
> when I discovered the HF radio negative wire had been connected 
> directly to the battery...
>
> So if the earth on the HF antenna had been properly connected AND 
> someone disconnected the battery using the isolating switch while the 
> 4WD was being used (on the chassis rail, easy to get to), the ENTIRE 
> current load of the vehicle would have been going through the HF radio 
> power cable negative conductor, then the RG58 coax and control cable 
> to the HF antenna to the chassis...   The control cables and coax were 
> buried under the flooring and I can imagine that a fire would have 
> been quite possible.
>
> I pointed it out to the SES guy who's eyes opened very wide... and I 
> moved the negative wire of the HF radio power cable to the body of the 
> car.
>
> I always play safe with my radio installs and never NEVER connect the 
> negative directly to the battery.
>
> Michael.
> VK5ZEA
>
>
>
>
>
>
> On 27/05/2012 16:07, Peter Bye wrote:
>> Re the below, why not??  I have done several mobile installs, most my 
>> own, but also for others.  I always connect both +ve and -ve direct 
>> to the battery, with a fuse on both.
>> I also use rig runners for power distribution.
>>
>> Cheers
>> de
>> Pete VK2MPJ
>>
>> On 27/05/12 14:32, Michael Carey wrote:
>>> ...
>>>
>>> Make sure you don't connect the negative wire to the battery... 
>>> always connect to an earth point on the body, close to where the 
>>> negative battery wire is connected...
>>>
>>> ...
>>>
>>> Michael.
>>> VK5ZEA
>>>
>>>
>>
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