Battery Isolator

[K7MDL]

I believe the can/cover is simply held in place by bend-over tabs over the plastic insulator plate with the posts. You can likely shove it back into the can and rebend the tabs, but power it off first (at both ends).

Be sure to scope out your bed drill sites under the bed floor for where they land relative to bed support rails underneath. I prefer to drill within 1/2" of the edge of a rail so the backing plate clamps the support rail fully thus stiffening the mount and not pull up and deform your bed floor. You can move the hole locations around a bit to achieve that if needed, as long as you do not move it too far.

 

[PaulT]

This is an equivalent part from Autozone.
or from eTrailer
There are a variety of mounting tabs and terminal types. At $3.50 each, just replace it if you are concerned about making a repair to the one you have..

Paul

 

[Stalking Light]

I feel your pain. My 100w solar alone won't keep up with my Dometic 65 and driving my truck 10 hours on a cloudy day won't fully charge my 2 camper batteries. I'm going to explore options when I stop by Adventure Trailers on the way to Expo. I suspect heavier wires and a different isolator are in my future.

 

[buckland]

Thanks Paul for that info.... that would be a bit easier than epoxy! (I'll save the old one in case as a back up)
And thanks K7MDL for the eyebolt advice too... appreciated.

 

[ntsqd]

Stalking, any idea what your truck to camper wire size is? It seems these are commonly undersized for cost and install convenience. I would say that 8 gauge is the minimum acceptable with 6 gauge being more performance oriented. Unless the alternator is the sole camper charge source I think 4 gauge is on the far side of overkill.

I'd try just the wiring first. If you make two changes at the same time you won't know what the problem was. I would suggest using an Anderson plug for ease of camper removal. Voltage drop is the performance killer, I used a pair of SB120s (Anderson Power Products SB120 SB Series 120 Amp Connector Kit) which are rated for 120 amps or roughly 3 times my max ever expected charge rate. The Solar Bob blog goes into excruciating detail on why sizing the wire based on expected current is the wrong approach in this application. Need to size the wire based on extreme minimum voltage drop.

 

[Wallowa]

Stalking, any idea what your truck to camper wire size is? It seems these are commonly undersized for cost and install convenience. I would say that 8 gauge is the minimum acceptable with 6 gauge being more performance oriented. Unless the alternator is the sole camper charge source I think 4 gauge is on the far side of overkill.

I'd try just the wiring first. If you make two changes at the same time you won't know what the problem was. I would suggest using an Anderson plug for ease of camper removal. Voltage drop is the performance killer, I used a pair of SB120s (Anderson Power Products SB120 SB Series 120 Amp Connector Kit) which are rated for 120 amps or roughly 3 times my max ever expected charge rate. The Solar Bob blog goes into excruciating detail on why sizing the wire based on expected current is the wrong approach in this application. Need to size the wire based on extreme minimum voltage drop.

Wire size, depending on year of manufacture, is a great question for Stan ...Stalking Light..you have a single panel @ 100w...would the current 160w panel be sufficient to keep the batteries up to snuff, assuming sunshine of course.

My head is spinning with all the solid info in this thread...Question: How would a FWC owner know if the alternator is providing enough current to charge a pair of batteries in the camper? Run the batteries down on voltage and then see if that is restored?

Thanks...

Phil

 

[K7MDL]

The precise way to know is to use a monitor that can measure current flow in both directions, and collect that data and compute KWH and min/max current and voltage. Then when running your loads and can easily tell if you are winning or losing and for how long. Looking at just the voltage will work over time, but it is not fast nor accurate. Good enough that it is all I am using for now since I know my loads well enough. As an electronics/electrician person, I ultimately will install a monitor because I always want to see the details. Right now I am on a 2 month road trip, part time in my camper, will have to wait to my return.

I am running #6 from my truck battery to the camper truck bed connector. It seems to be charging well enough, fast enough, but I am also driving many hours at a time these days. 7,000miles on the new truck and camper since I got them both in March, 6,000 of that has been this road trip from Seattle to Florida, soon to head back north, likely via Overland Expo in Flagstaff then up the Pacific coast.

When talking camper power, the newer campers also have marker lights. Mine are LED that draw 0.5A total light wire works fine. These need to come from switched power somewhere.

 

[PaulT]

When talking camper power, the newer campers also have marker lights. Mine are LED that draw 0.5A total light wire works fine. These need to come from switched power somewhere.

Marker lights on my 2014 Hawk are apparently driven directly by truck circuit via the third wire in the Marinco connector rather than by camper battery.

Paul

 

[Stalking Light]

Stalking, any idea what your truck to camper wire size is? It seems these are commonly undersized for cost and install convenience. I would say that 8 gauge is the minimum acceptable with 6 gauge being more performance oriented. Unless the alternator is the sole camper charge source I think 4 gauge is on the far side of overkill.

I'd try just the wiring first. If you make two changes at the same time you won't know what the problem was. I would suggest using an Anderson plug for ease of camper removal. Voltage drop is the performance killer, I used a pair of SB120s (Anderson Power Products SB120 SB Series 120 Amp Connector Kit) which are rated for 120 amps or roughly 3 times my max ever expected charge rate. The Solar Bob blog goes into excruciating detail on why sizing the wire based on expected current is the wrong approach in this application. Need to size the wire based on extreme minimum voltage drop.

I think it's the standard 10 gauge, will probably upgrade that. Will be running tests at AT Overland after Expo to see what's what.

 

[Stalking Light]

Wire size, depending on year of manufacture, is a great question for Stan ...Stalking Light..you have a single panel @ 100w...would the current 160w panel be sufficient to keep the batteries up to snuff, assuming sunshine of course.

My head is spinning with all the solid info in this thread...Question: How would a FWC owner know if the alternator is providing enough current to charge a pair of batteries in the camper? Run the batteries down on voltage and then see if that is restored?

Thanks...

Phil

When it's sunny and I use my 60w foldable along with the 100w on the roof it seems to work fine, but I don't always seem to have sunshine so I need to improve my truck charging. I have a generator but hate to use it and they are prohibited a lot of places I camp.

 

[JaSAn]

Wire size, depending on year of manufacture, is a great question for Stan ...Stalking Light..you have a single panel @ 100w...would the current 160w panel be sufficient to keep the batteries up to snuff, assuming sunshine of course.

My head is spinning with all the solid info in this thread...Question: How would a FWC owner know if the alternator is providing enough current to charge a pair of batteries in the camper? Run the batteries down on voltage and then see if that is restored?

Thanks...

Phil

200W solar, 208ah batteries running a 2.1 cu. ft. refrigerator, fan, LED lights, charging MacBook and iPhone. I am usually back to 100% by 11 AM. Only once this last year was I not back to full by end of day and that was in 90+F temps with heavy overcast. So far I have not even hooked up charging from the truck.

Quickest way to test charging is to run the battery down below 80%, start truck charging and use a volt meter and clamp on ammeter to see what is happening at the battery.

Question for the electrical gurus: If my solar charge controller is providing 15 amps at 14.5 volts and my truck is providing 60 amps at 13.5 volts (at battery), does the alternator current help charge the battery?

jim

 

[wuck]

Question for the electrical gurus: If my solar charge controller is providing 15 amps at 14.5 volts and my truck is providing 60 amps at 13.5 volts (at battery), does the alternator current help charge the battery?

jim

No. Simply speaking, current will flow from a given voltage towards a lower voltage. Now, if the camper connection was at the alternator instead of the truck battery, and the alternator voltage output was more than 14.5 volts, and there was no drop in the wiring or separator, then it would contribute. That's why a short, fat connection is best.

 

[K7MDL]

Marker lights on my 2014 Hawk are apparently driven directly by truck circuit via the third wire in the Marinco connector rather than by camper battery.

Paul

I ran the 3rd wire up to my engine compartment fuse holder to a fuse that was ignition switched using an add-a-circuit fuse tap. At 0.5A pretty much any circuit can handle it. That means the marker lights are on all the time the truck is running, but I was in a hurry. Ideally I would track down the trailer tail light wiring and see if that will work. In the 2016 F150 the trailer power is switched by relays and I have not verified if 0.5A will be enough to trigger the trailer power relay on. The truck detects each lamp and warns of a bad bulb/connection on the dashboard. It also trigger trailer configuration profiles for brake effort, miles towed, and backup assist pro feature.

 

[DannyB1954]

DannyB, do you have more than one of those relays in parallel? They're only rated for 30 amps normally.

I like the right Voltage Sensing Relay (VSR) or Automatic Charge Relay (ACR) because they won't close and connect the camper battery until the starting battery(ies) have been recharged. Searching either of those two names should pull up the many discussions that have been had here about them.

I don't own one, yet, but this is my ideal battery charger: http://www.amazon.com/dp/B005LBCVL4/ref=wl_it_dp_o_pC_nS_ttl?_encoding=UTF8&colid=1WJFO5EAJMISV&coliid=I1LW6VAW7Y7TI Takes the place of BOTH the isolator/relay and the solar charge controller. Treats the alternator's output as another charge source like a solar panel, picks the better power source, and applies the same charging logic to the camper battery(ies) regardless of the source.

You can buy the 5 pack and put them all in parallel. As Dynobob said in post #7 there may be a spare relay already in the vehicle. Or you can find a relay that you would rather use. If you do use more than one relay, how would you ever know it if one of them were to fail? It would probably have zero effect. The relays are rated for 40 amp. I don't think that charge rate happens in my application. You could use a 30 amp auto reset breaker to make sure that you did not overload the relay, but I have not had any problems.

 

[BFH4N]

Vic,

The CTEK D250S alone is rated at 20 Amps but in combination with the SMARTPASS, the rating is 80 Amps. Either way, the 20A rating applies to the MPPT solar charger aspect of the D250S.

Again, I haven't used mine enough to verify these numbers. I've installed a Trimetric monitor, so I should have some good data eventually...

- Bernard

 

[ntsqd]

You can buy the 5 pack and put them all in parallel. As Dynobob said in post #7 there may be a spare relay already in the vehicle. Or you can find a relay that you would rather use. If you do use more than one relay, how would you ever know it if one of them were to fail? It would probably have zero effect. The relays are rated for 40 amp. I don't think that charge rate happens in my application. You could use a 30 amp auto reset breaker to make sure that you did not overload the relay, but I have not had any problems.

If you are charging above 30A and one of let's say two paralleled relays did fail the other would be exceeding it's rating. How it would fail would be speculation, but that it would fail is almost certain. Perhaps not right away because there is some Factor of Safety built into them, but eventually.
I agree, charging over 30A is likely not a common thing. Possible though, and that was my concern.

 

[Vic Harder]

Vic,

The CTEK D250S alone is rated at 20 Amps but in combination with the SMARTPASS, the rating is 80 Amps. Either way, the 20A rating applies to the MPPT solar charger aspect of the D250S.

Again, I haven't used mine enough to verify these numbers. I've installed a Trimetric monitor, so I should have some good data eventually...

- Bernard

Ah, all good then.

 

[DYNOBOB]

Again... Thanks to the OP for starting this thread! We're leaving shortly for a 4 week run to Alaska and this could have bit us in the butt (the house battery not charging while driving because we ran it below the isolater cut out threshold). In case this situation rears it's head, I've wired a manual 60a switch that bypasses the isolater. It's hidden behind the access panel and in a minute I can pull the panel and get the house battery charging again. I have a handy little meter that plugs into the cig lighter and show where the house battery is.

If I knew six months ago (when I was wiring the truck to camper) what I know now, I'd have done things differently. It concerns me that FWC only provided one 10ga power and ground to run the camper while there are four unused pins in the camper plug. I could have run three 10ga grounds and three 10ga hot wires to the battery and still had an easy plug/unplug arrangement with three times as much wire/connector pins to carry the power.

Not having the time or energy to pull the camper and start from scratch, I opted to use the 10ga ground that runs thru the camper plug to the truck battery as a second power wire. For ground I dropped two 10ga wires from the buss bar directly to the truck frame. There are now two 30a power feeds from the truck charging system. I feel 100% better about this arrangement.

.

 

[rubberlegs]

Speaking of relays and isolators... we just got a Fleet on our Tacoma. I notice when I turn on the accessories, but don't fire up the engine, I get a warning on the dashboard. (I do this to listen to the radio or check mileage, etc.). This doesn't appear when the engine is started (and the alternator is working). So I think the camper battery and truck battery are connected, which the truck "doesn't like". Sorry, I forget the exact message.

The question is: we shouldn't use accessories very long, because the batteries will take power from each other? Sound right?

 

[Vic Harder]

Speaking of relays and isolators... we just got a Fleet on our Tacoma. I notice when I turn on the accessories, but don't fire up the engine, I get a warning on the dashboard. (I do this to listen to the radio or check mileage, etc.). This doesn't appear when the engine is started (and the alternator is working). So I think the camper battery and truck battery are connected, which the truck "doesn't like". Sorry, I forget the exact message.

The question is: we shouldn't use accessories very long, because the batteries will take power from each other? Sound right?

This does not sound right. The isolator should isolate the two systems - Truck and Camper - unless there is power coming in either via the alternator or via the solar panels.

Depending on the isolator capabilities and wiring, one of these systems is the "home" system and other the accessory/house/camper system. Using the truck as HOME, once the engine is running and alternator spinning, the isolator uses a voltage sensing system to check if it is safe to connect the two, to share the power coming in to charge the other system as well. Before that, there should be no connection and the truck should be unaware of the camper.

As for not using accessories long, are you talking truck or camper accessories? If camper, then the isolator should separate the truck from the camper batteries when the voltage drops, thus protecting the truck/starter batteries.