battery separator question

D

DonC

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getting ready for a trip tomorrow so firing up all the systems for a check.

I let the fridge run all night and was down to about 70% battery as measured on trimetric, about normal for a hot southern Calif night. There was no sun for the solar this am so I turned on the truck to check alternator charging. The trimetric immediately jumped to +12 amps, and then down to .3 amps in about 10 seconds. Then "click" and back to 10+ amps in 10 seconds, and "click" and back to .3 amps in 10 seconds. Round and round for 10 - 15 minutes always going to 10+, then back down to .3 amps. After about 15 minutes it settled at .4-5 amps, so no charging from the alternator.

I have never heard the constant on and off of the battery separator. Its at 1314A.

I assume its bad, but is there something else going on here too? Can I leave it like this or should I unplug from the truck for my trip tomorrow? I don't know that I have ever gotten any charging from the alternator, but I have certainly not heard this constant on and off the first 10 - 15 minutes.
 
I had a similar problem and it was one of the 30 amp autoreset breakers. Mine was near the battery separator. It was warm to the touch and i could hear it resetting often. In my Hawk, there "were" two. One under the hood and one by the separator.

Steve
 
I had the same problem before upgrading wiring from truck alternator to the isolator. My fridge would draw the battery down to about 70%. Once the truck started the current draw to the fridge would cause a voltage drop b/c the wire size was too small for the distance from alternator to isolator. This voltage drop caused the isolator to mistakenly think that the truck battery was low; hence shutting off the connection. It would keep retrying and cycling, never really charging the battery.

Once I replaced the wiring from 10 gauge (factory install) to 4 gauge (a bit overkill - could have likely gotten away with 6 gauge), the problem was fixed.

Hope that helps

Jason
 
This is is a breaker that opens when it thinks the current/amps is too high. Once it cools off a little, it will reconnect. Then it gets warm and disconnects. Mine just continued to open and close. Mine was designed to open if the current/amps exceeded 30 but it was opening at a much lower level. They are small silver metal rectangular devices that are about and inch long by about a half inch wide and deep. They are metal and silver in color. In my Hawk, there "was" one under the hood of the truck and one by the separator. I have replaced both of them with a different breaker. And, like a few others, I have added 6 gauge wire in parallel to the wires added at the factory.

With my improved wiring, I have seen over 50 amps of charge going from my truck alternator to the camper batteries, so things seem to be working well.

This is not a fuse that you replace when in blows. It will open when it gets hot (caused by excessive current) and will close again after it cools off. It is placed in line with your wires, just like a fuse. When you mentioned that you saw the amps going up and down, I remembered that I saw the same thing. Hope this helps.

Like a house, I am guessing FWC needs to follow guidelines and meet codes when they wire a camper. Although, that is just a guess.
 
oh yea, a re-wire is on my list of things to do

I guess to be safe, since I'm currently getting no charge from the truck anyway, I'll unplug. The separator does get very hot.
 
voltage at 70% was 12.8. when I plugged into shore power at 70% battery it spiked around 12 amps, and then settled in at 5 - 6 amps. this seems low also and I'm not sure what components are in play with this
 
You could try charging it up with shore power and then run the truck and see if the separator kicks in and out. Mine did that for a while and I found I had a bad battery, but even with good batteries I don't get much charge out of my truck.
 
In my case, even though the battery was reading 12.6 - 12.7 at steady state, it didn't take into account the voltage drop that occurred through the small gauge wire. This caused the voltage reading at the isolator to drop below the threshold for cut off, even though the alternator was putting out 14.1 volts.

Good point to try charging with shore power first to rule it out. If it fixes the problem, then I would guess that your wiring needs to be upgraded to avoid the issue (as was the case with mine).

Jason
 
Mine is switching on and off as I type this. We are in BC and it has been overcast for days, this is the first I've heard it. I guess I need to upgrade my wiring. Sigh. This is getting expensive/annoying.


www.mulehawk.com
 
MuleHawk said:
Mine is switching on and off as I type this. We are in BC and it has been overcast for days, this is the first I've heard it. I guess I need to upgrade my wiring. Sigh. This is getting expensive/annoying.


www.mulehawk.com
Click to expand...
I think even if you use welding cable the separator will switch out if your camper battery voltage gets too low.
 
[SIZE=11pt]If your camper battery(s) are too low, the SurePower battery separator will continue to open and close, open and close, open and close for a very long time, and you will NOT be getting much or any charge to the camper batteries. The main purpose of the battery separator is to protect the truck starting battery at all times. If you have 1 or 2 batteries that are very low inside the camper, and the battery separator opens up to allow charging from the truck battery to the camper battery(s), all of those batteries will start to equalize, meaning the discharged camper batteries will start bringing the truck battery down too. Once this happens the battery separator thinks the truck battery is too low, and will cut off the truck to camper connection to protect the truck starting battery. If the campers batteries are drained down too low, this will continue to happen for a long time and you won't be getting much or any charge to the camper battery(s).[/SIZE]

[SIZE=11pt]The only way to avoid this from happening and fix the problem, if you have depleted the camper battery(s) too much, is to plug the camper into to 110V/120V shore power and charge the camper batteries up to FULL again. Or put the camper batteries on a battery charger to get them back up to full again.[/SIZE]


[SIZE=11pt]Battery Separator Operation – How to check to see if it working or not . . [/SIZE]

[SIZE=11pt]The easy way to check things, WITHOUT charts, graphs, spreadsheets, multimeters, diodes, etc.[/SIZE]

[SIZE=11pt]How To: (this is best accomplished with 2 people)[/SIZE]

[SIZE=11pt]Step 1:[/SIZE]
  • [SIZE=11pt]Have one person sit inside the camper.[/SIZE]
  • [SIZE=11pt]Have this person push in the button on the basic FWC Monitor Panel that shows the FWC battery condition.[/SIZE]
  • [SIZE=11pt]It will usually (usually) be showing only 1 - 3 small red lights when the truck is NOT running.[/SIZE]
  • [SIZE=11pt]Have him/her continue to hold the small button in for a minute while the other person goes out and starts the truck engine.[/SIZE]
  • [SIZE=11pt]Once the truck is running, two different things should happen within just a few seconds . . .[/SIZE]
  • [SIZE=11pt]ALL 4 Lights on the small FWC battery monitor should instantly light up and show “Full Charging” – 4 lights lit up, instead of 1 - 3 lights showing on the monitor panel.[/SIZE]
  • [SIZE=11pt]You should also be able to hear an audible “CLICK” as the separator opens up and allows the current to start traveling from the truck battery/alternator system, back to the camper battery(s).[/SIZE]

[SIZE=11pt]The exception: If all 4 lights on the monitor panel light up when the truck is NOT running, you can only listen to the separator to hear if it opens, or not, when the trucks gets started.[/SIZE]

[SIZE=11pt]If these things above happen, the battery separator is working just as it should (typically speaking).[/SIZE]


[SIZE=11pt]If you did hear the “CLICK” and everything seems to be working OK that direction, then you can move on to Step 2.[/SIZE]

[SIZE=11pt]Step 2:[/SIZE]
  • [SIZE=11pt]One person is still sitting inside the camper, the truck is running, and the other person is still sitting in the truck cab.[/SIZE]
  • [SIZE=11pt]Have the driver turn the truck engine “OFF”.[/SIZE]
  • [SIZE=11pt]Within a very short time, things should start to happen right away.[/SIZE]
  • [SIZE=11pt]You should be able to hear that same audible “CLICK” as the separator automatically disconnects the truck battery from the camper battery(s).[/SIZE]

[SIZE=11pt]If this happens, the battery separator is working just as it should (typically speaking).[/SIZE]


[SIZE=11pt]If the separator is not making the audible “CLICK”, one direction or the other, then something is probably not right.[/SIZE]

[SIZE=11pt]If the battery separator is not opening, closing, the camper batteries are not getting charged, or the truck battery is not getting disconnected from the camper system when the truck is parked & not running, then something else could be wrong, or just different than what we have experienced in the past.[/SIZE]

[SIZE=11pt]Further testing will be required or replacement of the battery separator might be required.[/SIZE]


[SIZE=11pt]Stan[/SIZE]


.
 
My batteries are fine they are at 13v currently and it is still clicking on and off. Any other ideas?

Edit: I'll check what Stan said and see if it's working properly

www.mulehawk.com
 
Hey Stan - Thanks for stepping in with a great simple solution; however, I am not sure I agree with your statement that the low camper batteries will cause the isolator to keep switching on/off. This only happens because the draw from the alternator across the small gauge wire causes a voltage drop at the isolator which fools the isolator into thinking that the truck batteries are low (hence shutting off). As soon as I upgraded my wired (and therefore got rid of the voltage drop), the isolator clicks open and stays open, allowing full current flow to the camper batteries. This should not in any way affect the truck battery.

For example, today my battery in the camper was reading 12.4V (60% charge) on my Trimetric. It was cloudy and I was only getting 3 amps of power from the solar. I turned on the truck, and heard the click on the isolator after about 10 seconds. Then the Trimetric showed 20Amps of current being supplied to the batteries (about 17 from the truck alternator and the additional 3 from the solar still trickling in).

As Dr J said, this was also my biggest frustration with the electrical system. According to the Factory manual for the Superpower, the gauge of wire must be increased if the distance from the alternator to the isolator is beyond about 10 feet or so...this is the case for my camper and once I upgraded the gauge wire, the isolator worked flawlessly.

Just my 2cents

Jason
 
Jason,

Having not done many electrical upgrades it's a bit intimidating. That said, exploring independence which is what the FWC is for.

As I'm serious about the upgrade in performance with improved charging, I might as well start with the wire ga. An stock isolator before purchasing the BlueSea device.
What gauge wire did you use to replace the factory set up?
Were you able to use the factory plug between the truck bed and cabin?
I assume you replace all wires from the truck alternator to the battery.

Thanks,

T



Sent from my iPad using Wander The West
 
I ran #6 from my battery to a 60A breaker then under the truck and across to the front left truck bed wall, splicing to an Attwood connector which has wire pigtails. Then used the stock camper wiring and matching connector, it is a relatively short run. It has been trouble free with the stock ShurePower.

I have posted in other related threads recently on the same subject, demonstrating the effect of common wire size choices on voltage drop in our scenarios with number examples. There are diminishing returns when increasing wire size. #6 is a reasonable choice vs cost and performance for a 2 battery setup and will solve the problem. Going any bigger nets you only very small improvements in charge time. #8 is minimum, #4 is for oversized batteries and/or extra length runs.

If you feel you need to improve things a bit more, you can target the camper side wiring later, if at all.
 
Thank you for the timely response. I've decided to leave the 10ga wire in place and add a second 6ga wife to the truck side Atwood plug which has 10ga pigtailed. The two yield a 5ga equivalent. 2 tens will produce like a 7 gauge. Because of the camper side is choked by 10 ga it shouldn't hurt being supplied by the 5 ga equivalent.


Sent from my iPhone using Wander The West
 
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