conquerorforum.com
Sign up Calendar Latest Topics Chat Donate
 
 
 


Reply
  Author   Comment   Page 2 of 2      Prev   1   2
BarraM

Avatar / Picture

Member
Registered:
Posts: 85
Reply with quote  #16 
Hi Sharky. I guess its horses for courses. I would not say you will have any problems with the 490/Commanders charging. I would wait and see how you go. In my situation I was not completely happy with the amount of charge we were getting on extended periods bush camping. Probably in the end it all revolved around a faulty battery. However due to the long wiring from the Troopys alternator to the campers batteries (voltage drop) and the capacity of the vehicles alternator in charging the camper batteries, I rewired to a heavier gauge to reduce the voltage drop and installed the BC/DC to give me maximum imput and 100% charging. All the camper trailer people I know who have done this, think it is the best thing since sliced bread. But ................don't rush into it, see how everything goes. It can always be done later if required.

Cheers,
Mike
0
Sharky

Senior Member
Registered:
Posts: 131
Reply with quote  #17 
Hi BarraM,

It's great that I have good information to work with. I won't do anything to the wiring until I take the Commander for a spin. Thanks once again.

S
0
4fun

Senior Member
Registered:
Posts: 150
Reply with quote  #18 
Hi, at the risk of repeating what other people have explained already in many other threads and posts. The problem with charging batteries is that:
  • they usually don't like to be discharged for more than 50%, i.e. only 50Ah out of a 100Ah battery can actually be used (depends a bit on the type of battery). If you discharge the battery any further (and don't recharge it very quickly) it deteriorates. Discharge your battery too often beyond 50% and the battery is dead. What you usually notice first is that your battery doesn't last as long as it used to: time to start saving money for a new set of batteries (and think about a dc/dc charger as explained below).
  • to fully charge a battery it needs a certain voltage. The thing that decides what that maximum voltage is going to be is your alternator. The problem here is that the alternator sees both your car battery as well as your auxilliary battery in the camper but this second battery usually is a lot further away than the car battery.
This is where the problems start.
  • Electricity likes to flow through a thick wire. A thin wire makes it more difficult for the electrons to travel through, and this causes energy loss. So the thicker a wire is, the better.
  • Next to the thickness of the wires, the length is also important. A shorter wire means the electricity needs to travel less and this again means there is less electricity loss.
So back to our car + camper setup. The alternator 'sees' a car battery that is very close by and is connected through usually very thick wires (i.e. virtually no energy loss) and a camper battery that is far far away and connected usually through thinner wire. So there IS a certain amount of energy loss in that camper wire and that means that when the car battery is fully charged the alternator will reduce it's voltage a bit (so that it doesn't overcharge the car battery) but that the camper battery isn't even close to being fully charged because of the energy loss (read: voltage drop) in the wiring between the alternator and the battery. The only way the Camper battery can be fully charged in this setup is if the Alternator would raise the voltage higher (to compensate for the energy loss in the long wire) and it's not going to do that because that would mean that the car battery would be seriously over charged and the Alternator just won't allow that (and that's a good thing).

Anything that you put into that wire, a fuse, a switch, a relay, an Anderson connector, will add a bit of resistance that will make matters even worse.
  • A fuse is a really smart thing to have in a charging cable since it's a thick wire, running outside the car, prone to damage and therefore prone to creating a shortcut. Without a fuse a shortcut would mean total loss of power, possible damaging the car battery, risk of fire, and so on. Not a good thing, so even if a fuse creates a small resistance: you still want one.
  • Unless you want to permanently attach the camper to the tow vehicle an Anderson connector near the tow bar is a very handy thing. Basically unavoidable, but still ... it introduces a bit of energy loss.
  • To prevent the car battery from discharging during the night we usually put a switch (a.k.a. a solenoid) in the charging wire, and this switch will connect our camper battery to the alternator when the motor is running and disconnect when the motor is switched off, and hence protecting the car battery from being discharged. A solenoid/switch introduces a bit of resistance (energy loss) and hence - by definition - means that a Camper battery will *never* be fully charged.
So back to the beginning of the story. A battery at best delivers you 50% of it's capacity, and if it's not fully charged (as a result of a very long wire or a too thin wire, or because there are too many connections/switches/fuses in that wire) this means you'll loose a few extra percent of capacity and this is what many people may be experiencing: A 105Ah battery that isn't charged to more than 95Ah and that can't be discharged below 50Ah.

A much better solution is a DC/DC charger. A DC/DC charger is a bit of electronics that replaces a solenoid switch so you don't need that anymore, but most importantly the DC/DC charger pumps up the charging voltage to a level that fully charges the camper batteries. To work well the DC/DC charger needs to be mounted close to the battery that it charges (or else the same problems with long cables apply again) but the length/thickness of the wire between the alternator to the DC/DC unit is suddenly much less important. It still needs to be of good size, with well soldered connections, and no longer than neccessery, etc but it's thickness/length doesn't have the same severe impact anymore on the charge (for the technically inspired, the voltage drop will be compensated by a slightly higher current).

So summarizing:
  • don't discharge batteries below 50%, or you will reduce their lifetime
  • use a DC/DC charger so you can always get a battery recharged to 100% of it's capacity
  • install the DC/DC charger close to the camper battery
  • use good wires of decent thickness
  • make sure all connections are well soldered
  • install a fuse in the wire close to the alternator (or car battery if that's where the power is taken from)
  • forget about solenoids. They will never fully charge a secondary battery.
0
BarraM

Avatar / Picture

Member
Registered:
Posts: 85
Reply with quote  #19 
4fun
Good to have this explaination posted again.
The only thing I would add, is the Conqueror has a Low Voltage cut out to prevent the batteries dropping to less than 50% (causing battery deteriation) and rather than a DC/DC charger I would recommend a DC/BC charger that also does the same thing with solar imput.

Cheers,
Mike
0
SVX17

Avatar / Picture

Registered:
Posts: 394
Reply with quote  #20 
For 2014 -
Extreme's = No
Evo's = yes.
As of now the new RedArc BMS 1215S2 will be standard in the Evo's.
0
BarraM

Avatar / Picture

Member
Registered:
Posts: 85
Reply with quote  #21 
Hi Robo,
Sorry I should have said BC/DC not DC/BC. The Redarc BC/DC is a charger that utilises maximum imput from solar in the same way it does from DC current. I am sure Ctec has a similar model out there that does the same thing. Redarc is an Australian owned company and therefore gets my attention. I was recently speaking to an Autoelectrician who is running a Tafe Course "DIY Electrics for Recreational Vehicles" and Collyn Rivers, the guru who writes all the Camper electric books, has had imput into this course. He said BC/DC chargers were the way to go and that it will not be long before every campertrailer manufacturer has a BC/DC charger as standard equipment due to their efficiency.
Just make sure your Ctec model does what the Redarc BC/DC does.

Cheers,
Mike
0
SVX17

Avatar / Picture

Registered:
Posts: 394
Reply with quote  #22 
Conqueror have just switched to RedArc for all their inverters, battery chargers & BMS's.

Nice work !
0
Jeff B

Avatar / Picture

Junior Member
Registered:
Posts: 29
Reply with quote  #23 
Have they? about time i insisted on a redarc BMS but it got all too hard, got ctek an a box and installed the bms the first weekend i had the trailer. they are a great unit highly recommended!! just wire from anderson to bms in heavier gauge cable for best performance, i used 6B&S right thru from starter
0
VK6BP

Member
Registered:
Posts: 45
Reply with quote  #24 
We are getting the Extreme (delivery in 4 weeks ) which does not come standard with Redarc however you can upgrade to it if you need to / wish to. $500.  If you want to upgrade you need to ring dealer not factory unless you bought direct.




0
Previous Topic | Next Topic
Print
Reply

Quick Navigation:

Easily create a Forum Website with Website Toolbox.