Is my SurePower 1315 going bad?

photographix · 02-08-2014, 11:24 PM

When warming the glow plugs and starting my 2008 6.0, I have noticed that the SMB-supplied house battery meter green light goes out. After the engine is running for a couple minutes, the green light comes back on again.

After reading the "Battery Isolators,Separators, and Switches?" sticky thread, this is what I assume is happening:

1. The 1315 is sensing a drop in the van battery voltage, and is using the house batteries to "help" the van batteries start the engine.

2. The alternator is recharging both the van and house batteries, making the green light come on again.

I had new van batteries installed in May 2013, so I don't think they are the problem. They could be bad, but how can I test them? Or how can I test the 1315?

Warning: I am an electrical noob, so please type slowly when responding....

**daveb** · 02-09-2014, 12:26 AM

SMB did change the auto combine to a push button switch that needs to be engaged to assist start via the Surepower. I don't like or want it to always combine the house and starting systems when cranking the engine.

If you have another issue like a short or bad starting battery connections it can cause the same issue. Check all the starting battery connections.

Pull the ground going to the Surepower separator. If the engine labors to start, your starting battery (gas version) or one/both of your diesel batteries has gone south or there is a bad connection somewhere.

It's normal to have the separator take several seconds to confirm a charge status and close.

If the house system is bad you'll know it b/c the house voltage will be in the red by morning. Of coarse it all depends on your 12v house load.

Lastly, even new batteries can go bad and all it takes is one cell on a starting battery to take its brother down. It's why you should always replace both starting batteries with new one of the same age and condition.

Dave

photographix · 02-09-2014, 03:57 PM

Quote:

Originally Posted by daveb

Pull the ground going to the Surepower separator. If the engine labors to start, your starting battery (gas version) or one/both of your diesel batteries has gone south or there is a bad connection somewhere.

It's normal to have the separator take several seconds to confirm a charge status and close.

If the house system is bad you'll know it b/c the house voltage will be in the red by morning. Of coarse it all depends on your 12v house load.

Thanks, Dave, that helped a lot!

I disconnected the ground from the 1315 and taped up the connector so it wouldn't short on another terminal.

I ran around and did some errands in the van, and it starts up just fine without the assist from the house batteries. In fact, it may even be starting a little easier now, but it is much warmer outside today, too, so that might just be my imagination.

Is there any harm in leaving the ground disconnected, aside from the fact that I won't be able to use the house batts to assist in starting the engine if I have to...? I can always reconnect the wire if that need arises.

I'm thinking that the 1315 is on its way out. I am considering replacing the 1315 with a Blue Sea unit. Would it be worth the $$ and effort?

Ford_6L_E350 · 02-09-2014, 06:05 PM

Without the ground the 1315 won't charge your house batteries while you drive.

Mike

**daveb** · 02-09-2014, 06:11 PM

You could cut in a switch so you can disable the separator but you have to remember to close the switch or the house battery will not be charged by the alternator when the engine is running and the solar if you have it won't charge the starting batteries once the house battery is topped off. Batteries are very expensive and not worth risking installing a disable switch...just too easy to forget it's off. It's best to put a push button switch on the circuit that is hooked to the ignition which sends a signal to the separator commanding it to close during engine startup. That is what SMB started doing before they switched to the Blue Sea 7622.

Even on my 7622 I wired it to not close for 30 seconds during engine startup. So normally the separator is closed during daylight because the solar is charging house and starting batteries. As soon as I turn the ignition to start, the 7622 opens. After 30 sec it closes if it see's a charge voltage from either side. If I need to assist start, I can manually connect the two battery systems.

One issue that I worry about is if you have a heavy short or dead starting batteries, the buss wire should be fused heavy enough to turn the starter and the buss wire needs to be heavy enough to handle the load.

I have had issues with the Surepower separator but many haven't. So far I've had zero issues with the 7622.

Good luck

photographix · 02-09-2014, 11:04 PM

After thinking about it, taking in your comments, and doing some reading on boating forums, I think I'm going to take the plunge and replace the 1315 with the BS 7622.

As for installing, I'm going to put it in the same location as the 1315. I gather that the lugs on the 7622 are larger than the ones on the 1315. Can I just enlarge the holes in the existing connectors in the van and be okay? Or should I get new connector rings?

I'd like to install the remote switch, probably putting it on a bulkhead behind the driver's seat. Any advice on this?

**daveb** · 02-10-2014, 01:54 AM

My remote is above the side barn doors. That is up to you. I rarely use it except as a visual annunciator. For that alone it's worth it. As far as lugs, they just need to be rated for the current draw. Your biggest draw would be to jump start. With the 7622 you can combine the battery banks and let the low starting batteries absorb a charge over several minutes, then attempt to start. It's just a good move. A direct short is another issue.

Scalf77 · 02-10-2014, 08:18 AM

I am not sure that you have diagnosed the 1315 correctly. If you are worried about start assist then remove the wire from the start assist tab on the Sure-Power Unit, then see if the symptom you have described goes away? The other question I would have are do you have solar and was it charging, or were you plugged in before trying to start? I am not sure what supplied monitor you are talking about, so I don't really understand what the green light means. But start assist does not work the way you described it. The Sure Power does not sense that your starting batters are low and then connect. It only connects if one battery is above 13.2 volts and disconnects below 12.8 volts. It is possible that if you have solar that the sure power was already connected, turning on the glow plugs brought the combined voltage below 12.8 and disconnects and then connected above 13.2 when the alternator came on. The start assist tab would force closure of the 1315 with 12 volts applied. Not sure how it is wired.
I'm not against your idea of upgrading to the Blue Sea unit, I am just not convinced that you currently have diagnosed the problem correctly. If you do upgrade the unit you should put on new connectors instead of enlarging the existing ones.

-greg

photographix · 02-10-2014, 12:26 PM

Quote:

Originally Posted by Scalf77

I am not sure that you have diagnosed the 1315 correctly. If you are worried about start assist then remove the wire from the start assist tab on the Sure-Power Unit, then see if the symptom you have described goes away? The other question I would have are do you have solar and was it charging, or were you plugged in before trying to start? I am not sure what supplied monitor you are talking about, so I don't really understand what the green light means. But start assist does not work the way you described it. The Sure Power does not sense that your starting batters are low and then connect. It only connects if one battery is above 13.2 volts and disconnects below 12.8 volts. It is possible that if you have solar that the sure power was already connected, turning on the glow plugs brought the combined voltage below 12.8 and disconnects and then connected above 13.2 when the alternator came on. The start assist tab would force closure of the 1315 with 12 volts applied. Not sure how it is wired.
I'm not against your idea of upgrading to the Blue Sea unit, I am just not convinced that you currently have diagnosed the problem correctly. If you do upgrade the unit you should put on new connectors instead of enlarging the existing ones.

-greg

The meter I am referring to is the one that SMB supplies and plugs into one of the house 12V outlets.

When the house battery drops below 12.5V, the green light goes off. The green light indicates "full", according to the instructions.

I don't have solar (yet), so that variable is out of the equation.

With the wire connected, ignition turned to ON (not START) to let the glow plugs warm up, the house battery meter indicates a drop in voltage. As I understand it, the 1315 is sensing a need to help the van batteries. However, the van batteries start the engine fine on their own. So why is the 1315 linking the two systems when it isn't necessary?

With the wire disconnected, the house voltage remains constant during engine start.

Since this started happening, I have noticed that the house batteries have started to decline. I see this in the SMB meter while running the fridge overnight, and observing that the volts drop quicker than they used to. On our trip last week, I would see that the volts had dropped in the morning to 12.1, and started out at 12.7 about 10 hours before. The only items running overnight were the fridge, CO and LP detectors.

Scalf77 · 02-10-2014, 02:04 PM

So just try to remove the wire going to the Start Assist, it should be going to 12 volts when you have the key in "on" position, that would be what turns on start assist. (the start assist circuit does not sense any voltages). By removing the ground wire, you would disable start assist, but also the battery monitoring function. So if you just remove the wire to the start assist tab:
__ - Lamp

| - Start assist
__
- Ground
I apologize for the crude drawing, but there are three tabs.

It should be right above the ground that you removed. With the start assist removed you should still be able to charge the house with alternator, as long as you hook the ground back up.

-greg