A question about batteries in series - how do you prevent fireworks when
you connect them? With hundreds of Ah of battery, it can get a little scary
when doing things that can make sparks, especially inside a vehicle
Sean WA1TE
On Thu, Sep 14, 2017, 14:07 K7XC Tim Marek <k7xcnv1@gmail.com> wrote:
> For what its worth...
>
> I was a very competitive Single and Multi Op Mountaintop Portable in the
> June VHF contests for over 20 years. In that same time period during the
> Sept and January events I elected to be a highly motivated ROVER, Placing
> in the Top 10 USA many times. As such I learned things along the way you
> might find useful.
>
> As to how to power your ROVER station I did all the wrong things possible
> and most of the time got away with it... Most of the time... Those times
> when it didn't go my way are very memorable, not to mention life changing
> as in each event I had to think my way out of the situation, learning from
> my failures, and never repeating them again.
>
> With that background in mind, I recommend a pair of 6 Volt Deep Cycle
> Batteries in Series, The kind that are used in Golf carts and such, as your
> primary means of DC power, and here is why.
>
> When I was a full time RVer (IE: Lived full time in a 5th wheel trailer for
> 2 years in TX) I had the regular 12V deep cycles replaced with a pair of
> the 6V units Increasing the capacity by at least a factor of four for only
> a 25% increase in Cost. We were able to dry camp for 7 days before they
> needed to be recharged where a pair of standard 12V RV Deep Cycle batteries
> would barely last a weekend.
>
> As to charging them while ROVER, I would install a second 12V DC Alternator
> and wire it to only charge the golf cart batteries, including its own High
> Current Fuses to prevent fires as you can literally Arc Weld with this much
> available Current. Some would say my plan is too extravagant and costly to
> be realistic but ask yourself this... Would you even stop to think "Is it
> worth it to add a new band your Rover station?" We all know the answer is
> Hell Yes, Full speed ahead, Costs be damned as I want those high value Qs
> and Mults. Adding 222 almost doubled my score with all those Points and
> Mults it made possible. Yet all of that is at high risk of failure if your
> main source of DC power is not up to the task.
>
> All those radios, rotors, keyers, etc are all powered in most cases with
> the vehicles main battery while never shutting down the engine, which by
> the way is what Ambulances do to maintain A/C and Power. Do you know why
> they switched over from gasoline to diesel powered engines? Too Many Engine
> fires from idling in the hot days of Summer while staged around the city
> waiting to be dispatched.
>
> What do most of us drive? Gasoline powered vehicles with charging systems
> barely able to maintain the current necessary to keep it going during a
> winter evening when the cars electrical system is maxed out powering
> Headlights, Heater blower, A/C pump to dehydrate the air, the car stereo,
> interior and running lights, not to mention the engine itself and charge
> the battery. Add to that Ham Radios with aftermarket amplifiers and you
> soon will find any weak link in the system and fry it.
>
> Depending on where you breakdown (ALL vehicles will breakdown at some
> point), what supplies you have on hand, and the ever changing weather, your
> life may be placed at risk over the chance to play radio... Ponder that a
> bit as I have been there... The vehicle dead on a tall mountain without the
> needed parts on hand to effect repairs and move on. Luckily I planed ahead
> and had two coolers filled with bottled water on ice and a container of
> food to last several days as I waited for a friend to deliver the needed
> parts to get going again.
>
> In a Sept contest long ago I found myself on the side of the road with a
> toasted Alternator & dead battery after 3 days of driving 1700 miles while
> operating an impromptu ROVER station after our Mountaintop Operation in
> Central Nevada was rained out.
>
> The truck died as I pulled into Western Reno leaving me stranded on the
> side of the road till I came up with the idea to use the generator and
> battery charger to get me the rest of the way home. I ended up hanging my
> EX650 Honda Generator on the back of the camper shell with 16 bungee cords,
> a short extension cord went over the shell in through the passenger wing
> window to the 35 amp battery charger while its DC cables ran out the same
> window, under the hood to the new battery I bought earlier in the day.
> After 30 minutes of charging I was able to start the truck and continue.
> The head lights were dim but it got me to my driveway. I'll never forget
> turning off the engine after 3 days on the road, beat-up and exhausted...
> only to take a few seconds to realize something was still running... The
> generator dancing on the back door of the camper shell! I stopped and took
> a picture before turning it off and dragging myself up the stairs and into
> the house where I fell into bed fully clothed and didn't move for 8 hours.
>
> Again I was lucky that I had in the early planning stages made sure to have
> the battery charger and generator with me as part of my Emergency Tool KIt
> or I would have never got home without a costly tow bill or a long walk
> while exhausted to get the parts and repair it on the side of the road in
> on and off rain showers, Not a fun prospect.
>
> If I was to EVER rove again. I would have a pair of Golf Cart 6V batteries
> with me in bolted down metal battery boxes running off their own Alternator
> under the hood.
>
> Just a few observations from someone who has been there and rode that style
> of contesting long and hard. Being ROVER isn't for everybody... it is one
> of the most demanding physical and mental forms of contesting ever known.
> Lots of challenging planning, building, traveling and operating go into
> each ROVER trip with no two ever being even remotely the same. I certainly
> miss it but now, over 30 years since my first effort, Growing older (58)
> has certainly slowed me down so I stay home and appreciate the hard work
> put in by the new crop of operators who carry on the tradition.
>
> Best of luck guys!
>
> 73s de Tim - K7XC - DM09jh... sk
>
> Adapt, Overcome, Succeed!
>
>
> On Thu, Sep 14, 2017 at 3:41 PM, Terry Price <terry@directivesystems.com>
> wrote:
>
> > On the K8GP rover we use a pair of Interstate 4DM's in parallel, about
> 120
> > lbs each. These feed a Jacobs Electronics 100A DC-DC inverter to maintain
> > 14.0 V to our TE Systems bricks which are very voltage sensitive. We also
> > feed a couple of MFJ super boosters which have been very problematic and
> > I'm
> > planning to replace them with N8XJK regulators. These are charged by an
> > aftermarket 200A alternator on my old Dodge van when roving. We have a
> > commercial 200A solenoid relay that isolates the radio power system from
> > the
> > vehicles battery during operation so we don't kill the vehicle battery.
> We
> > have a third marine battery from Walmart that can be switched from
> parallel
> > to series to give us 24v for certain items.
> >
> > If you have unlimited funds, I would suggest Trojan batteries, probably
> > some
> > of their 6v units. They seem to be about the best next to the BIG UPS
> > batteries used in commercial UPS's that are actually re-buildable.
> Keeping
> > the batteries well maintained is the key to long life. I use a
> > microprocessor controlled 40A charger/conditioner when the vehicle is not
> > in
> > service. The other end of the spectrum is to use the marine batteries
> > branded by Walmart. They are about $100 each but there is a Walmart just
> > about everywhere and their exchange/warranty isn't too bad. The ones I've
> > used have been satisfactory in service.
> >
> > For roving service, as detailed in other posts, the CCA rating isn't the
> > important thing, it's the reserve capacity. The 4DM's I use are rated at
> > 15A
> > draw for 12 hours each. Our rover idles at just under 20A with everything
> > turned on and running. Peaks current during transmit is just under 100A
> > (SSB
> > and CW). We typically operate 2 1/2 to 3 hours per stop and make 100+
> QSOs
> > during that time. We are down to 12.3 volts usually when we move to the
> > next stop. If we have little drive time between stops, we augment the
> > charge
> > with a small generator running my 40A charger.
> >
> > I'm not sure our system is optimal but it's been working for two years
> and
> > the batteries seem to be as good as they were new. If you are interested
> to
> > see what true sickness is, checkout
> > http://directivesystems.com/wp-content/uploads/sites/2/
> > 2016/05/Building-the-
> > super-rover-Dayton.pptx
> > <
> http://directivesystems.com/wp-content/uploads/sites/2/2016/05/Building-the-%0Asuper-rover-Dayton.pptx
> >
> > which is our rover version 1, we are up to version
> > 2.0 which now has pneumatic masts on both front and rear and a new desk
> > layout.
> >
> > 73,
> >
> > Terry - W8ZN
> > K8GP Rover
> >
> > -----Original Message-----
> > From: VHFcontesting [mailto:vhfcontesting-bounces@contesting.com] On
> > Behalf
> > Of Steve Stahl
> > Sent: Thursday, September 14, 2017 9:39 AM
> > To: Steve (K1IIG)
> > Cc: vhfcontesting@contesting.com
> > Subject: Re: [VHFcontesting] BATTERIES
> >
> > In my current rover setup I'm using 2 group 24 deep cycles that I tie
> into
> > my truck with a rv charging relay.
> > Then I use a battery booster (N8XJK )to draw from the deep cycle
> batteries.
> > My main rover radio is a Yaesu 847 which is very voltage sensitive.
> > This works great, I never have a issue as far as power goes during a
> > contest.
> > MURPHY on the other hand. ....
> >
> > On Sep 14, 2017 6:01 AM, "Steve (K1IIG)" <stephen.tripp@snet.net> wrote:
> >
> > Barry,
> > FYI, Car batteries are not the best choice for Roving but will work. Car
> > batteries are designed to be charged and discharge just like in the car.
> > They also do not like to be float (trickle) charged. To get around this
> > people use a smart charger that removes the charge when it reaches full
> > charge and then kicks in when it drops below a certain level. Car
> batteries
> > are designed for CCA cold cranking and not designed for reserve usage.
> > Marine batteries are designed for that type of service and can be float
> > charged with no ill affects hence are a better choice for Roving.
> Running 2
> > car batteries in parallel might not be the best choice either. When not
> > being charged, they will drain against each other if not disconnected.
> They
> > do make a dual deep cycle marine battery that can perform as a car
> battery
> > and reserve battery. I probably did not explain this clear enough so
> check
> > out this site for a better description. https://marinebatteryguy.com/
> >
> > Years ago I was told there are only 6 manufacturers of wet (flooded) cell
> > batteries, Gould, Exide and a few others. Here is an interesting cut and
> > paste I found.
> > How many car battery manufacturers are there in the world?
> > As of May 1, 2013, there are three major automotive starting flooded
> > battery
> > manufacturers in the United States. There are four absorbed glass-mat
> (AGM)
> > starting battery manufacturers and there are four flooded deep cycle
> > battery/major deep cycle battery manufacturers in the United States.
> >
> > There are dozens of brands of batteries made to different specs.
> Interstate
> > seems to be one of the most popular car battery.
> >
> > 73's
> > Steve
> > K1IIG
> >
> >
> > Interesting battery discussion. Also interesting that the IC-910 seems to
> > take significant d.c. power.
> > I've recently acquired an Icom IC-9100 and I'm trying to choose the 13.8v
> > portable power source. Last weekend in the Sept VHF contest the rig was
> set
> > up for the first time with my SUV, and I discovered that my usual single
> > automotive (Sears Diehard) sealed lead-acid battery is insufficient. This
> > battery has worked well with an FT-897 and an IC-7100, but the larger
> power
> > drain of the IC-9100 causes the rig to reset itself on xmit.
> > Is there a way to calculate how long two car batteries in parallel would
> > last?
> > I already have a small Honda generator although I don't usually bring it
> > along unless I'm using an amp.
> > Thanks in advance,
> > Barry K7BWH
> > Seattle CN87us
> >
> > -----Original Message-----
> > From: VHFcontesting [mailto:vhfcontesting-bounces@contesting.com] On
> > Behalf
> > Of Alan Larson
> > Sent: Wednesday, September 13, 2017 3:42 PM
> > To: vhfcontesting@contesting.com
> > Subject: Re: [VHFcontesting] The digital modes and the Sept contest
> >
> > > Hi Alan. That is useful info re the ic910. I'm just curious what
> > > type of batteries are you using.
> > >
> > > I've had considerable success running my ic7300, FT736, multiple
> > > Icom706MkiiG's, an icom 735 IF radio, 300 watt amps on 50 and 144 MHz,
> > > transverter, etc.. from two 12 V 100 AH Agm style batteries.
> >
> > Over the years it has varied, but typically I would have 25 - 30 amp
> > hours
> > of sealed lead-acid batteries in parallel with the starting battery of
> the
> > diesel VW. Solar would be attempting to hold that up.
> >
> > > I took another 100 AH battery with a solar panel with me during the
> > > June contest and used it to run an inverter that in turn powered the
> > > battery chargers for the computers and also powered another charger to
> > > top off the two radio batteries. I had ample power for approx 6 to 8
> > > hours of operation including some MSK144 at close to full power on 50
> > MHz.
> >
> > When operating from a small motor home, I have used 200 AH of battery
> > feeding an inverter feeding a switching power supply to run the rig. In
> > the
> > more space limited Volkswagen, a small Honda generator has proven to be
> the
> > most convenient option. (This includes consideration of the difficulty
> of
> > getting all the items inside the Jetta.)
> >
> > For low power operation, I would still choose solar if available, but I
> > wanted full power from the rigs.
> >
> > Alan
> > _______________________________________________
> >
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