Jump to content


Photo
- - - - -

Hawk Shell Electrical Questions: Shore power and more

power battery charger AC/DC adapter voltage monitor

  • Please log in to reply
5 replies to this topic

#1 UmkaAndHawk

UmkaAndHawk

    Newbie

  • Members
  • Pip
  • 9 posts
  • LocationColorado

Posted 23 February 2020 - 06:23 AM

Yesterday I got my 2019 Hawk Shell, single 12V battery, no solar (yet).
I have a lot of newbie questions:

1. I don't know how fast it will charge from the truck. I don't know the voltage drop is for the isolator diode so can't even estimate. Any experience out there?
[edit: my shell has the Blue Sea Automatic Charging Relay, model 7611 with a 0.05 voltage drop. I still have no experience or way to know how fast it will charge while driving, but one question down!]
2. Which voltage monitor should I get? There are plenty of cheap-o units on Amazon. Is there a reason for a fancy one? Don't I need one? i have no way to know what the battery's status is...what will happen if I run it until dead...am I ruining it?
3. I'm going to mount an on board charger/AC-DC power...but which one. FWC uses the IOTA30-IQ4 ($185 on Amazon...oddly the 45 is cheaper!) If I eventually get another battery this sounds good. My local dealer was going to install an NOCO-Genius 10A one...not so good for an additional battery, or will it just take twice as long to charge?
3b. are batteries mounted in series or parallel
4. Do I need a switch for the charger, or can I leave it connected to the battery when not plugged in
5. If I'm plugged into a camp ground, with 110 AC/15 amp line will this be enough or IOTA? Can I use a two plug adapter or not enough juice?


Thanks for any help or advice! Thanks to all!

rjz

Edited by UmkaAndHawk, 23 February 2020 - 04:57 PM.

  • 0

#2 Vic Harder

Vic Harder

    Get's a "charge" out of camping!

  • Members
  • 2,449 posts
  • LocationCalgary, Alberta

Posted 24 February 2020 - 06:28 AM

1) No way to know that without a battery monitor

 

2) You don't want a voltage monitor. You want a real battery monitor with a shunt.  I like the Victron gear, but this might work well too

 

3) Iota is what FWC uses.  I use Noco 2600.  both are good

 

3b) 6V batteries are wired in series, 12V batteries in parallel

 

4) you should be able to leave it attached to the batteries

 

5) Yes, one 15 amp connector is enough.  15A*110V = 1650Watts.   Or 150A at 12VDC


  • 0

2006 Silverado 3500 ext cab 8' bed LBZ

2012 ATC Puma Shell build - https://www.wanderth...012-puma-build/

Power considerations thread - https://www.wanderth...e-power-scotty/

 


#3 Beach

Beach

    Senior Member

  • Members
  • 569 posts

Posted 24 February 2020 - 05:18 PM

I will add, there are several variables to the answer on #1. Battery type, battery size, temperature of battery, alt. output, volt drop from alt. to the battery, how low was the battery. Yes a battery monitor is great to have and provides usable data, however it is not imperative to have one. I use a digital voltmeter to monitor my battery's state of charge. It works well for me but if have minimal draw on my battery, my solar is only 60 watts and keeps up.  We rarely stay in one spot for more than 2-3 days, then back we're back on the road and the truck alt. is doing the charging.


  • 0

#4 bfh4n

bfh4n

    Senior Member

  • Members
  • 211 posts
  • LocationLovingston, Virginia

Posted 24 February 2020 - 10:11 PM

1: An isolator is not just a diode. That would be too much voltage drop (~0.5 V). It's a relay that senses when the truck is running and closes to connect the camper battery to the truck battery.

 

If you don't have the isolator and wiring yet, you are in the perfect position to implement a much better setup. There are at least a couple of new (and one old-standby) dual-input chargers available that can actually control the charging of the camper battery both from the truck and from solar. The solar part is an ordinary MPPT charging system. The truck part does a similar thing: It generates a charging voltage and current that is appropriate for the state of the camper battery, drawing from a totally different voltage of the truck battery. I have seen the one I have (CTEK 250) charging the camper battery at 14.4 Volts and 20 Amps from the truck battery at 13.6 Volts. Just connecting the batteries together could never do that. A charger like this is not so sensitive to voltage drop in the truck battery wiring as the isolator setup. So, you wouldn't need huge wires.

 

The CTEK charger has been around for a while and I can vouch that it works well. I think I heard that Vectron sells one now, too. And there is an Australian company supplying one.

 

2: I agree with Vic that you should get a real charge monitor (that can measure current, as well as voltage), which will allow you to keep track of the stare of charge of your battery. The old standby TriMetric works fine. Vectron is fancier. They may have one that integrates with their dual-input charger.

 

3 -5: The IOTA 30 Amp AC-powered charger works well and can safely be left connected to the battery long-term. It does draw a very small current from the battery when not powered (about 40 mA, as I recall), but it's probably not enough to warrant installing a disconnect switch. Even a small solar setup should be able to keep up.

 

The IOTA will work fine connected to a 15A 120V shore-power circuit, with power to spare for other reasonable AC loads. (There is nothing going on in a normal FWC camper to justify the 30A input connector that they supply.) To paraphrase what Vic said: 30A at 12V = 360 Watts or 3A at 120V. Being less that 100% efficient, the IOTA draws more (about 7A max, I think).

 

- Bernard


Edited by bfh4n, 25 February 2020 - 03:41 AM.

  • 0

2014 silver Fleet front-dinette

2007 Tacoma Access Cab 4WD TRD V6 6-speed

 


#5 UmkaAndHawk

UmkaAndHawk

    Newbie

  • Members
  • Pip
  • 9 posts
  • LocationColorado

Posted 09 March 2020 - 08:45 PM

 

3 -5: The IOTA 30 Amp AC-powered charger works well and can safely be left connected to the battery long-term. It does draw a very small current from the battery when not powered (about 40 mA, as I recall), but it's probably not enough to warrant installing a disconnect switch. Even a small solar setup should be able to keep up.

 

The IOTA will work fine connected to a 15A 120V shore-power circuit, with power to spare for other reasonable AC loads. (There is nothing going on in a normal FWC camper to justify the 30A input connector that they supply.) To paraphrase what Vic said: 30A at 12V = 360 Watts or 3A at 120V. Being less that 100% efficient, the IOTA draws more (about 7A max, I think).

 

- Bernard

Thanks! This is how I think I'm going to do it, connect the Iota to the battery, using two additional leads from the charger to the battery. 
This isn't how FWC does it...they run the charger before the main cutoff switch to the battery. There may be circuit breakers and fuses in between, I don't know for sure. 
Is it alright for me to do it your way/my way? 
Any other comments welcome.


  • 0

#6 rando

rando

    Senior Member

  • Members
  • 1,113 posts
  • LocationColorado

Posted 09 March 2020 - 10:54 PM

Given the choice, I would use a battery charger instead of the IOTA converter.   In fact,  I would use neither as I have never plugged the camper in, and rely on solar for my charging, but that is just me.   Something like the Victron Bluesmart line does essentially the same thing as the IOTA, but is fully configurable (and monitorable) so if you want to switch to lithium or what ever come next, you will be ready to go.   The IOTA is not very configurable. 

 

 You can wire this on either side of the cutoff switch. 


  • 0

2016 Fleet Flatbed

2016 Toyota Tacoma






Also tagged with one or more of these keywords: power, battery, charger, AC/DC adapter, voltage monitor

0 user(s) are reading this topic

0 members, 0 guests, 0 anonymous users