Battery Isolators,Separators, and Switches?

[Mike Wilson]

Phil,
It is the stock alternator on a 2000 E350 7.3l PSD. I don't know exactly how much current it puts out but it is adequate for everything. Most people have the feeling that a larger alternator is the answer but it is not. It is getting enough voltage at the battery terminals to cause current to flow. I believe the existing alternator is adequate.
I do know that after the house battery is about half way down, I can get about 30 amps delivered by the Battery charger, an Inteli-Power 9140. After a while it drops to the high 20's and continues down as the battery becomes more charged. This is what it would NEVER do with the old original system.

To monitor what is going on, I installed a shunt resistor from the negative leg of the house battery to ground. It is 1 milliohm so it drops little voltage. It is dropping one millivolt per amp. That voltage drop is measured by a volt meter and gives me 0.1 amp resolution. At 30 amps it drops only 30 millivolts.

I would like to have a better (more universal) way of turning on the inverter after a delay. One way is to apply the alternator 12 volts after a delay leaving the inverter switch on but that caused mine to intermittently go into over current and shut off when the 12 volts was applied. I got mine to work by putting in some delay circuitry and a relay that acts like the external ON/OFF switch. If this inverter ever gives up, I can't simply connect up another one since it does not have the delay and on/off stuff. I may look at this again since it represents a reliability/repair issue. Although it has been doing fine for the last 10 years. If you look at the schematic I provided, you can see two diodes which are the diodes in the battery separator that came from Sportsmobile. One of the diodes is not connected. A jumper will revert it back to the original way until I fix the problem that may exist. Have not need to so so.

Mike

[moorefc]

I have been thinking of changing out the Surepower 1315 in my SMB, and the new posts in this thread were motivating as I never liked the heat off the solenoid. The funny thing is my Texas build book shows the fuse to the separator and states "if the separator's fuse is blown no charge from the vans alternator will go to the Aux Battery". Hmmmmm. Hadn't noticed that before and am thinking how does that work? (it doesn't).

So tested it by monitoring when starting the van. I always assumed it was connected to the START circuit. Thru this test found it is tied to the RUN circuit,and pulling the fuse the 1315 did connect the banks per design. So all the time the ignition switch was in accessory position we were tying both banks together AND draining over an amp heating the van to boot! Amazing....So someone that wired it told the SMB book builder..Yada Yada Yada...fortunately we never got to the "both batts drained" no start condition while in the boonies....


Now on to the 7622... and now the system will actualy work as "intended"
Incredible what assumptions can do...and some lively thread discussion.
Thanks

[Railvan]

I have read through this thread, and tried to absorb as much as I can, but my head hurts... I have basic electrical knowledge, but am not an electronics expert at all. Please see if this info is enough to help me diagnose what is going on with my van.

The set up:

A 2006 Ford E350, 6.0 diesel, from SMB West with RB50, poptop and SMB 4x4. Bought new 2-2006. Had solar panels and controller installed at SMBW in 9-2007. Two Solara panels, Blue Sky 2000E controller, and Inteli Power 9100 Charge Wizard were installed by SMBW. The panels died sometime about two years ago. I pulled them off this spring 3-2018 and rebuilt the poptop to fix leaks, cracks, etc, and installed two Renogy 150 watt panels a couple weeks ago.

The original Ford van starting batteries lasted about a year from when I bought the rig and I changed them out. This second set of starting batteries lasted until 7-2014. This second set died while I was miles from the nearest town. I had no warning they were going bad. I was on a trip on a four day weekend and the van had been starting and running fine until the last morning. It would crank but not fire. Luckily I was with a friend who gave me a ride to town. A tow truck driver made the trip out to the trail where I was camped, a two hour drive, and then my van started up fine... That was a $500 tow bill for no towing, but it would have been four times that much if I was towed out of there. The batteries installed in 2014 after this incident are two 65-76 Centennial starting batteries, and one Fullriver DC210-12 Deepcycle AGM camper battery. These are what are in the van now.

Two days ago the starting batteries would not crank the engine, just clicking sounds as I have heard before when batteries die. Again, no warning ahead of time, as it ran fine the day before. I came back a few hours later and it started once, with a slow crank before firing. I let it run a few minutes and turned it off and it would not restart. It would click and the gauges would flicker up and down.*The camper battery showed 13.09 volts when the van would not start. The Scan Gauge on the engine showed 9.9 to 11 volts after the first successful start and when it would not start the second time. This was read with the key on but the engine not running.*

The van has been connected to 120 volts for a day since this event, and it started fine tonight. A relay in the power controller area has been clicking on and off since I connected it to 120 volts. This concerns me that I will wear it out or burn it out.

The lack of warning that the batteries are low is the root of what bugs me about the van and how the batteries are controlled. From what I have read, the controller connects the camper battery to the van batteries when the van batteries are low, and this automatic feature masks any problems until it just won't start one day. The van has been hooked up to 120 volts for most, but all, of the time since last winter. It is always parked outside. To have dead starting batteries happen two weeks after installing new solar panels makes wonder if this is just a coincidence of timing, or did something happen that drained the batteries after I hooked up the new panels? I changed nothing else about the system when I installed the new panels, other than they are 300 watts total, and the old Solara panels were less. I don't know which model Solara panels were on it, as the SMBW receipt does not say what panels they installed.

Questions:

When the van is plugged into 120 volts does it charge both the starting batteries and the camper battery?

Is four years the reasonable life span for starting batteries? Maybe nothing is wrong, it's just time for batteries? (I'm really hoping the camper battery is also not needing to be replaced as it is much more expensive.)

Are AGM batteries the way to go now for starting batteries?

Should I pull the fuse on the relay so it does not burn up, or is it needed to charge all the batteries?

Is there a way to change the system so that this suddenly dead battery problem will not happen in the future? A different controller maybe? A warning would be nice as this makes me very leery to camp in remote spots.

Thank you all very much for this thread!

Brian

[Scalf77]

Hi Brian,

Not sure what relay you are talking about, but since it is a 2006 Sportsmobile we will have to assume that is the Surepower 1315, you should confirm.

Questions:

When the van is plugged into 120 volts does it charge both the starting batteries and the camper battery?

If you have the Surepower 1315 (it is bidirectional) , it should be able to charge both the house and starting batteries

Is four years the reasonable life span for starting batteries? Maybe nothing is wrong, it's just time for batteries? (I'm really hoping the camper battery is also not needing to be replaced as it is much more expensive.)

Yes, it could be, it is hard to gauge with out knowing how you use it. 4 years would be a little on the low side. It appears the dual battery 6.0 always have more battery problems than others.

Are AGM batteries the way to go now for starting batteries?

It would not hurt, while the charge profiles of both are close, a problematic issue could be long time floating. Specifically this goes along with your previous question, if you plug in all the time or have solar your starting battery being in float a large percentage of the time (because of bidirectional separator) can dry out your starters and make them die earlier. It won't kill them outright, but may be the difference between 4 years and 5 years. This is even more important if you plug in all the time'.

Should I pull the fuse on the relay so it does not burn up, or is it needed to charge all the batteries?
Not being sure of the "relay" or being sure how exactly Sportmobile installed your Surepower 1315 it would be hard to say. All indications are that they put the fuse between the run circuit and and the start assist tab. This is wrong, but it appears to be in their documentation. If you want to stop the sure power from clicking if that is what is clicking, pull the ground wire. It will not prevent the shore charger from charging your house battery. If keeping the Surepower 1315 put a 10 amp fuse between ground and the ground tab in the future.

Is there a way to change the system so that this suddenly dead battery problem will not happen in the future? A different controller maybe? A warning would be nice as this makes me very leery to camp in remote spots.

First not using anything connected to the start assist tab on the surepower. At most I would use a momentary switch, that you could hold in when you think your starter batteries may need assistance.

My view point on this is a little different here than others, but I usually disable the bidirectional function on the separator. I figure Ford designed the system to keep the starting batteries healthy, why should I try to mess with that. If I am not driving my van often, I re-enable the the bidirectional feature and top of the starters. This also minimizes the number of cycles on the Surepower relay. I believe the bidirectional (and specifically the start assist ) feature also tends to mask the normal symptoms you experience from degrading starters. I just monitor the voltage, make notes of what you read after 24 hrs, 48 hrs, 7 days. You should see something different if your having an issue.

From a high level I expect one of your starters is bad, the fact that you plug in and the "relay" is cycling could possibly indicate an issue. When connected the drain from a possible bad starter brings the overall voltage below 12.7 volts and it disconnects, after it disconnects the shore charger brings the voltage above 13.3 volts and the relay connects, the cycle continues.

If you have an original Surepower, it might be a good time to make a change, as they are prone to dirty contacts.

hope this helps, feel free to PM if you wish.

-greg

[Railvan]

Thanks, Greg. I appreciate your time very much.

I found PDF docs for the Surepower 1315-200 and the InteliPower 9100 online. Neither of these docs were included in my owners binder from SMBW. These help me to understand this system much better.

"Not sure what relay you are talking about, but since it is a 2006 Sportsmobile we will have to assume that is the Surepower 1315, you should confirm."

I went out and dug around and found the Surepower 1315-200. It is mounted with the "front" of it facing the wall, and all the wiring and control equipment is under the seat in my RB50 plan, so I had never seen the front label on it until I stuck the cell phone camera down in that area.

"Are AGM batteries the way to go now for starting batteries?

It would not hurt, while the charge profiles of both are close, a problematic issue could be long time floating. Specifically this goes along with your previous question, if you plug in all the time or have solar your starting battery being in float a large percentage of the time (because of bidirectional separator) can dry out your starters and make them die earlier. It won't kill them outright, but may be the difference between 4 years and 5 years. This is even more important if you plug in all the time'."

Thanks. Good info. I'm planning to get new van batteries this winter. Rather be safe than stuck.

"First not using anything connected to the start assist tab on the surepower. At most I would use a momentary switch, that you could hold in when you think your starter batteries may need assistance."

This sounds great.

"My view point on this is a little different here than others, but I usually disable the bidirectional function on the separator. I figure Ford designed the system to keep the starting batteries healthy, why should I try to mess with that. If I am not driving my van often, I re-enable the the bidirectional feature and top of the starters. This also minimizes the number of cycles on the Surepower relay. I believe the bidirectional (and specifically the start assist ) feature also tends to mask the normal symptoms you experience from degrading starters. I just monitor the voltage, make notes of what you read after 24 hrs, 48 hrs, 7 days. You should see something different if your having an issue."

To highlight the important part to me:

"I believe the bidirectional (and specifically the start assist ) feature also tends to mask the normal symptoms you experience from degrading starters."

This is EXACTLY what I am experiencing, again. I am thinking a toggle switch that I can use to connect the camper battery to the starting batteries when the starting batteries are low would be my preferred choice. Also, a digital display of the starting batteries voltage, mounted next to the Solar Boost 2000E controller, would allow me to keep an eye on their volts easily.

Question: Is there a way to not have the camper battery automatically connect to the starting batteries, and still have my solar panels charge all three batteries? I understand adding the switch between the 1315 and the starting batteries so I can connect them only when I want to, but I'm not clear on how all the batteries would get power from the solar panels in this design?

Thanks,

Brian

[Railvan]

Photos showing the layout of the SPI 1315 and InteliPower 9100 in my 2006 RB50 SMB.

[Scalf77]

Originally Posted by Railvan

Question: Is there a way to not have the camper battery automatically connect to the starting batteries, and still have my solar panels charge all three batteries? I understand adding the switch between the 1315 and the starting batteries so I can connect them only when I want to, but I'm not clear on how all the batteries would get power from the solar panels in this design?

Thanks,

Brian

The switch I was talking about was between Surepower and Ground. The Solar Charger and Shore Power Charger are both on the House battery side of the Separator. For the Solar charger to charge the starting batteries it needs to go through the separator. I used this for awhile while having the Surepower. It essentially turns the 1315 into a uni- directional unit.



The relay is put between the ground line and the Surepower 1315. There are two contacts to the relay inputs normally open and normally closed. We run a ground to the normally open input, and we run a switched ground to the normally closed. When the switch is closed, your Surepower will work as normal. If you close it, you will be able to connect starters to your shore or solar charger.
If you leave the switch open, than it will be disabled. When the van is running the run circuit is hot and will energize the relay the normally open circuit will now close, and make the Surepower work as normal. You house battery will now be connected to your alternator. Let me know if you need a parts list.

You can also check out this post, which explains a little about the Surepower.
http://www.sportsmobileforum.com/for...5-a-14502.html

And if you choose to upgrade to a Bluesea 7622 I have a similar mod for it.

-greg

[Quigley-76]

Perfect switch is the real deal.

[Mike Wilson]

I have sort of been off this forum for quite some time so I would like to ask whether anyone has any REAL data on the charge rate one can achieve with these newer systems with macho relays and "smart" switching. If the large AGM battery is really down, how many amps can you deliver to the house battery.
I built a relay system that worked but I found the limiting factor was the monster cables you need to get the voltage drop way down. Is that what people are doing? That is why I ended up using an inverter (12 volts to 120 volts) to send power to the good charger. It sits close to the house battery and does a good job of sticking 30 amps into my 200 A hr AGM when it is down.
Any good data out there on charge rate?

Mike

[Scalf77]

Sure, here you go.



This is with 2 gauge cable from start bat to BlueSea 7622. During high amp charging the battery would be in the bulk phase and the voltage drop would not be an issue, as the current comes down so does the voltage drop Pushing 40 Amps I am below 1% drop
-greg