Norway Assault Vehicle MKIII

Actually a nega/posi ammeter would be a better idea. It would show
directly whether amps were going in or out of the battery, the actual
number of volts driving don't really matter that much.

 

Oh?

So if I see some # of amps going into a battery that is sitting at only 9V,
everything's A-OK, is it?

The battery voltage tells you the state of charge. If the voltage goes down
over time, the battery isn't being charged. This is quite easy to see if you
have even the cheapest DMM capable of resolving 0.01V. If the battery
voltage stays constant, the alternator is supplying enough current to drive
the load. If the battery was supplying part of the load current its voltage
would go down over time.

It's quite true that using a voltmeter across the battery, I can't tell exactly
how much current is flowing in or out of the battery, but I can tell if the
battery is charging or not, just not the number of amps.

So, by using a voltmeter, I can tell if the battery is being charged or drained,
(but not the magnitude of the net current, I admit) and I can also tell what the
current state of charge of the battery is. Two useful pieces of information
instead of just the one.

 

Indeed. All those years fiddling with dynamos and mechanical control
boxes made me very aware of this. What joy it was to see the flickering
needle eventually edging in to the + zone as you revved up with the
lights on.

--
+-------------------------------------------------------------------+
| Pete Fisher at Home: |
| Aprilia Shiver Yamaha WR250Z/Supermoto "Old Gimmer's Hillclimber" |
| Gilera GFR * 2 Moto Morini 2C/375 |
+-------------------------------------------------------------------+

 

Not necessarily but as a guide for the uneducated, amps going in/out is a
better measure than the potential difference which may be applied to an
unknown circuit and the individual you are advising is, even putting it
kindly, uneducated.

No you cannot. All you can do is make assumptions based upon an
incomplete knowledge of what you believe the circuit may contain. I will
grant you that if you are confident that every component in the circuit is
functioning correctly it is reasonable to make those assumptions but as
any competent techie will tell you, assumptions are not always correct.

 

Well, yes, you do need at least a minimal understanding of what you're
looking at to benefit from using a voltmeter. But as I say, you cannot
tell the state of charge from looking at the ammeter.

You said a mouthful when you said that.

Anyway. If there are two or three people in the Norge party who can pool
their pitiful ignorance, having a voltmeter in their midst is still going
to be more useful to them than an ammeter.

 

Having the sense not to go in the first place is, IMHO, going to be much
more useful but these kids need to learn and if it is the hard way then
sobeit.

 

Is there an over/under on hardships?

 

On the bikes I have with ammeters fitted, they're just a rough measure
of vibration rather than anything to do with electrickery. On at least
one of them I think the needle is somewhere in the bottom of the
instrument, having given up its fight against metal fatigue.

 

There's a smoker on board, but as is typical, he'll be of no use.
Rolls his own, see - you need to be specific: a ready-made smoker is
what is needed.

 

They are fucked then. It needs a tailor made type, for the silver foil in
the fag packet for emergency fuses.

 

In my banger days, I had the effrontery to demand electric start of a
MKI Triumph 2000. Battery charging facilities being a bit scarce at
the track and jump starts similarly (depending on how unpopular I was
that week) I installed an ammeter to show what was going on. Now, I've
never been a master of vehicle wiring, so it didn't come as a complete
surprise when there was a small firework display when it came to
slotting the ammeter in the dash panel.

What was a bit surprising was the reaction of the car when on the
second time of asking, I ignored the sparks from around the ammeter's
casing and slammed the thing home. The starter churned and the engine
fired up. This was quite the shock, considering the ignition was
switched off.

I'd used reasonable wire for the ammeter circuit: T2000 headlight wire,
IIRC - blue with a red trace is indicated in my mind's eye - and it
took a little while to melt. Fortunately I was too startled by the
fuckawful noise from the engine (the starter was still running) to grab
and rip the wire, as within a couple of seconds the insulation dripped
off the wire and onto the floor - then a connection melted and it all
went quiet, apart from a couple of theatrical wisps of smoke and the
sound of my sphincter on overdrive.

Project Ammeter was smartly shelved.

My lovely old 1965 Humber Sceptre (of wot I've writ before) was of
similar vintage, I guess, to your Jag. It was positive earth when I
got it, equipped with dynamo and control box. It had a full dash,
though, including both voltmeter and ammeter: the voltmeter to monitor
the battery state, the ammeter to inform of the condition of the
charging circuit.

It also had a FOAD battery tray, which was dead useful as it would take
a light truck battery - this compensated adequately for the voltmeter
and ammeter both living in the red most of the time. For the times it
didn't, there was always the starting handle.

It was a happy day when having installed the Holbay motor from a Hunter
GLS, complete not only with a pair of 40DCOEs hanging off one side, but
an alternator hanging off the other. Negative earth conversion
complete, the rev counter, radio and ammeter all let the magic smoke
out, some more interestingly than others - but at least the starting
handle became irrelevant.

 

I had one of those, although mine was a Super Sceptre. My pride and joy it
was until I broke a half shaft. So, after a trip to the local scrappy I
got it a new (less broken) one. A bit of cursing and swearing and a
weekend lying in the gutter outside my flat and I was ready to roll. A
few days later and driving up the A127 on my way home from work and there
was this vibration from the back somewhere. I slowed down a bit and it
seemed to go away. Returning the pedal firmly to the metal and off on my
merry way I continued, for about 3 seconds. Then there was this enormous
great bang and the front of the car leapt into the air like it was doing a
wheelie. Not having a lot to look at except bonnet and sky out the front
I glanced into the rear view mirror only to see a gert great cloud of
smoke and sparks that would have done justice to the output from the back
end of Thunderbird 2. Panic slowly subsided along with my speed but not
the noise of tortured metal. It seems that my attempts at economy by
reusing the bolts to reattach the propshaft to the diff was not as good an
idea as I had first thought and the two had parted company. During it's
brief moment of freedom the propshaft had punched a hole through the
floorpan and gouged a 2 inch deep valley about 20 yards long in the road
behind me.

Happy days.

 

Heh.

About 25 years [1] I had a job which involved installing 2 way radios.
One of the customers was an ECC quarry in Devon.

It was my first job in a supervisory position and I was keen to impress.
It was also the first couple of weeks in the job and I was pretty green.

The quarry manager was a completely unreasonable bloke who loved to
shout at contractors (and I assume staff) and he'd been lied to by the
salesman that sold him the system (yes, we can install overnight, no it
won't take more than about half an hour a vehicle etc.etc.)

So I agreed to work on a sunday and to be at the quarry at some horrible
hour, 5:30AM or so. There were six critical vehicles to do but these
were unbelievably large things (cab more than ten feet off the ground,
massive wheels or tracks).

I did about four vehicles in the day and was knackered and wanted to
call it a day. Quarry manager had a good shout and I agreed to work on
and do the remaining two. I think they probably took me 2-3 hours each.

Came to the last one (a massive 'shovel' which would just about fill a
lorry with one scoop) and it was 48v. The radio equipment was 12v. All
other vehicles were 24v and I had a supply of voltage droppers to drop
24v to 12v. I didn't have anything for 48v. Thought about wiring two
in series across the battery to give me 24v and a third across this to
give me 12v. Thought this was a stupid idea and so instead wired it
across the 'bottom' battery.

Eventually got done, got home after midnight.

Got into the depot at 8 on Monday to find a series of answerphone
messages[2] starting at 5:30AM.

Apparently the radio in the shovel had gone up in smoke and there was a
queue of tens of lorries (M25 tarmac delivery...) waiting to go.

Rang up, got shouted at, drove for two hours. Complete chaos on site
with disgruntled lorry drivers (contractors, paid by the load), pissed
off site manager, pissed off shovel operator). On inspection the
antenna cable and battery lead had just about vaporised. What had
happened was the vehicle was turned off using an earth isolator. Of
course wiring the radio to the battery neg and then earthing to the cab
for the antenna had by-passed this. When the operator went to start it
the wiring just 'caught fire'. The company I worked for got a bill for
several tens of k. Not sure if it got paid.

I fixed it, drove back to the depot and the MD was waiting for me. I
guess he'd agreed with the quarry manager to work as a tag team and he
had a good old shout at me.

Rather pissed off at the time since I didn't even get paid overtime for
working on the Sunday.




[1] How the **** did that happen? How did I stop being 'young',
'pre-children' and moving to the point where children go to
university??? Next thing I know I'll be Pete Fisher[3]

[2] Pre wide-spread cellular use. I didn't have a carphone then despite
much of the job being installing them. Plus I *think* this was
pre-handheld anyway.

[2] Oh... wait a second...

 

Anyone ever told you you're a bit of an arrogant prick?

 

Unfortunately those days are gone. The newer fuses have removed the
need for such skills. Maybe that's why people have stopped smoking?

 

Eh? My feeble attempt at humor. Not a dig at you or
the Norway trip participants in any way.

 

Sorry... a bit trigger happy...

 

Same here. The last 20 years have just vanished in a flash.

 

You needed some of this...
http://starlight.com/poof.html

 

Genuine LOL here. " Mr Pot, we have a Mr Kettle for you on the red
courtesy phone"