Re: Battery related assistance Reply #25 – June 11, 2019, 02:04:19 pm Ok. I'll work on it over the next few days and report back when I have logical reading. Thank you. Quote Selected
Re: Battery related assistance Reply #26 – June 15, 2019, 09:00:30 pm I had some time to tinker with it today. I pulled the cables off the isolator and tested them for the voltage and they matched up with the reading directly on the batts so obviously I didn't get the terminals cleaned well enough last time. I removed the isolator so I could get to it with a wire brush on a drill and got them cleaned up good. I noticed that the resin or epoxy that they use to seal the top of the isolator has a spot that has lifted between the left and center terminals. (see pic) I don't know if that's indicative of it getting too hot or if it's just because it's almost 30 years old. But I thought it was worth mentioning.Attached is a pic of the readings now. Yes, the batteries are a bit more run down at the moment. Hopefully that doesn't affect the results of what we are trying to figure out.Jeremy Quote Selected
Re: Battery related assistance Reply #27 – June 15, 2019, 09:06:33 pm If it were me, I'd change that out. Quote Selected
Re: Battery related assistance Reply #28 – June 15, 2019, 10:12:26 pm Jeremy,Those readings on the isolator battery posts (before engine start) look a lot better this time. Good work!You are still showing voltage on the center post with engine off. That is one potential strike against the isolator.With engine running, the center post (ALT) voltage looks OK. The house battery post is down 1.3 volts, which is more of a drop than we would like to see. The start battery post is only down 0.2 volts, which is much less of a drop than normally expected. These two results are the second strike against the old isolator.And strike number 3 is the physical condition. Isolator looks pretty rough, and the lifted potting material is not a comforting sign.Personally, I would add a second vote for a new isolator.OR, investigate the possible alternatives to a diode based isolator. Several threads on the Forum about that subject. For instance:Schottky based isolator vs combinerNew battery isolatorBattery Isolator Quote Selected
Re: Battery related assistance Reply #29 – June 15, 2019, 10:55:45 pm I am quite happy with my cole hersche smart isolatorForetravel Tech Talk Quote Selected
Re: Battery related assistance Reply #30 – June 15, 2019, 11:05:52 pm All new coaches come with combiners Quote Selected
Re: Battery related assistance Reply #31 – June 15, 2019, 11:33:38 pm Thanks, all for your input. I'll decide what to replace the old isolator with and see if that clears up the issues that I'm experiencing. Might be a week or two but I'll report back my findings. Quote Selected
Re: Battery related assistance Reply #32 – July 09, 2019, 11:55:38 pm Well I guess it's time to report back what I have done with this thing. I started researching isolators and combiners and I gotta say that my head started spinning rather quickly. It isn't the most exciting reading material out there!I decided to go with a Victron Cyrix-ct Intelligent Battery Combiner for a couple reasons. It was inexpensive (I think it was $42 on Amazon) and the installation seemed easy enough for me to handle...which is important since electronic stuff isn't my strong suit.I decided to go with 2 12V golf cart batteries for the coach which I purchased at Batteries Plus for just over $100 ea. I had to rout out the plywood base that I put in the battery compartment a bit so they would fit under the stairs. It was close but I made it!I took Old Toolmaker's advice and bought a couple of the cheap 12V LED Voltmeters and built a panel in the compartment next to the stairs as you walk in. Then I printed the Battery SOC Chart that Chuck sent on some industrial label material so that all of the information is right there and understandable at a glance for a dummy like me, and I don't have to open up the stairs to see the condition of the batts, which I love. In all, I probably spent around $275 for everything.I haven't truly tested things out on a trip yet, but it appears that I've accomplished what I set out to do. I want better performance from the house batts which I think will be obvious when we really start using it. I needed to get the batteries isolated so both wouldn't drain down. The Victron is doing its job. I wanted the salesman switch to work properly and once I had everything connected properly, it worked just fine.I reattached the outlet that was hanging in the tank dump bay so I could plug the charger back in. It seems to be doing its job now in charging the coach batt. Running the engine with the alternator charging will charge the engine start battery until it hits a certain voltage and then will also charge the coach battery. (I think that's why it's called a combiner!) It was hard for me to get everything mounted straight and pretty because that combiner is pretty small and those 4GA cables are huge and not very flexible.From here, I don't know if there should be further testing that should be done but in my eyes, things seem to be working properly, which they haven't been since 'Stretch' has been in the family. But please feel free to correct me if you think something else should be done.I truly appreciate knowledge that you-all are willing to share. It's been an overdue learning for me and your advice made it a whole lot easier. Thank you. Quote Selected 1 Likes
Re: Battery related assistance Reply #34 – July 10, 2019, 08:34:45 am Congrats! I'd say you did a great job of straightening out your battery compartment, and getting control of your charging system. Well done!The Cyrix-ct looks like a great combiner. Since it is bidirectional, it should also keep both battery sets charged when on shore power.https://www.victronenergy.com/upload/documents/Datasheet-Cyrix-ct-120A-230A-EN.pdfOnly thing I might add is a way of watching the voltage of both battery sets while driving the coach. I don't know what you have on your dash for volt meters. If there is one in your instrument panel, it probably shows chassis (start) battery voltage. Easy to tell - watch the gauge and turn on your headlights. If voltage drops, it is showing start battery voltage.To monitor the coach battery from driver seat, if you have a lighter socket on the dash, it might be connected to the coach battery. If so, you can utilize a inexpensive "lighter plug" volt meter. If no lighter socket, then another small surface mount volt meter can be stuck on the dash. Photo below of two volt meters and lighter plug meter on my dash. Very handy for a quick check of voltages while driving. Quote Selected
Re: Battery related assistance Reply #35 – July 10, 2019, 12:51:01 pm Hi Chuck. I do have an in-dash monitor...see pic. I guess this opens up another round of questions. I'm questioning the reliability of the volt meters in the monitor since they aren't even close to the readings from the new ones that I hooked up at the batteries. Perhaps that is indicating connectivity issues to the dash?? You can also see that when the monitor is on, there is a line across the bottom of the display so it doesn't fully show all of the info that it's meant to. When the batts are down, it's even worse. It's the same when I switch it to camera. That's always bugged me but I think I just thought things were getting old.When you talk about watching the voltage while driving, am I assuming correctly that it is to prevent overcharging? And if so, what can/should be done about it?Jeremy Quote Selected
Re: Battery related assistance Reply #36 – July 10, 2019, 03:57:44 pm When driving you want to know if the battery charging rate (battery voltage) is too high OR too low. Either condition could be the first indication of a problem which requires further investigation. Better to catch such problems early before batteries suffer.I suspect that the Audit display voltage is incorrect. Check the voltage at your batteries with your multimeter, then see what the Audit display and your new volt meters show. If the Audit display battery voltage is way off, then it is useless.Figuring out exactly where the Audit display gets its battery voltage reading may be difficult. You MIGHT have a schematic in the owners manual that shows the wiring inputs to the Audit ECU and where they originate. There is a diagram posted in the Forum library for the Audit 760 and 1160 systems, but I think your system is a earlier iteration (Audit 700) since it has fewer display features.https://www.foreforums.com/index.php?action=media;sa=item;in=3270#viewitemMany members have replaced the aging Audit displays with newer more accurate and reliable technology. Since doing so will involve coming up with 3 new systems (tank levels, battery voltage, and rear view camera) it might require a lot of reading of pertinant Forum threads on the different subjects before you make any choices.If you decide to go down that path and have questions, you should start a new thread for each topic. Quote Selected
Re: Battery related assistance Reply #37 – July 15, 2019, 11:58:42 pm When I was installing the new volt meters, my multimeter was consistent with them. I'll check it again but it likely won't happen until our camping trip in a couple weeks. I'll keep an eye on the batt levels and will just use the audit display for the tank levels. For now I'm anxious to see how the dual 6-volts perform compared to having to run a small generator with a 100' cord in the bushes all day!Thanks again for the direction!Jeremy Quote Selected
Topic: Battery related assistance