Clipper, House Battery Circuit

[masseyfarm]

Applies to the Clipper, but this information may be of general interest.

Decided to service my #2 House Battery circuit when I had extra time this morning. Last service on #2 circuit was in Sept. 2011 and the unit has been on shore power most of the winter, so a check was necessary to have confidence that no problems might exist.

On the Clipper I have two independent solar systems dedicated to the House Battery Circuit. Before battery service, it is best to disable these systems either by a manual switch, or be covering the solar panels so that they do not generate power and sparks when working on the batteries.

Turn off the coach main power disconnect located at the entrance door.

Undo the ground cables first and then the positive cables and take care to avoid grounding these positive cables to protect fuses in the solar system circuits.

On the Clipper, it is necessary to pull the Trojan T105's to get access to clean, service and test each battery.

All batteries were in excellent shape and after cleaning up the compartment, were rotated and reinstalled with a small amount of dielectric grease on each post connection.

If you are not familiar with series/parallel wiring, you should make a chart of the battery compartment wiring diagrams for your records.

When I finished and tested the system, I could initially get no power beyond the battery compartment. I checked the wiring for bad connections, and traced the problem to the house disconnect solenoid which was hung up. With no load on the circuit, the solenoid would not activate.

I turned on the interior lamps and reset the switch, and all systems engaged. That solenoid does not get used on our Clipper except when I do battery service.

My Trojan T105's all tested good so I felt there is no need to do an equalization at this time. If this procedure in necessary, the equalization control is accessed by removing the systems control panel above the stove, and setting the dip switches on the back side.

Ready for the road.

Dave

[masseyfarm]

You will notice that I have covered my battery retainers so that they are unable to cause a short if something comes loose in the battery compartment. The metal retainers/hold downs have been fitted with a bicycle tube and taped to protect from inadvertent shorting, even with the wrench when you are tightening the cables.

My battery box is sprayed with "rock guard" to again insulate from accidental shorting when I am working in that confined space.

An accidental short in this confined space could result in a disasterous gas explosion, so take all precautions when working on your batteries.

Dave

[masseyfarm]

I did my house #2 battery bank pull/test/service/clean today and again took the opportunity to refresh the battery bay and relocate some wiring.
My T105's showed excellent balance again on hydrometer test, and required very little distilled water to top them off. This 10 1/5 month cycle the CLIPPER was on a land tether the majority of time with short day or four trips.

I now have completed all the maintenance on the 3 battery banks on the CLIPPER and will schedule the next for the fall after our return from ON, NY, via Reno.

The T105's are dated summer 2009 and I expect they will give good service for another 2 years before worrying about replacement.

Again, use extreme caution when working in your battery bay and take the time to disable your solar systems so they do not suffer damage or cause a spark in that confined area.

Dave

[masseyfarm]

On the Clipper #137, OEM installation was 2X53 Watt SOLAREX panels wired though a controller located at the entrance step, and then harnessed to the house fuse box at the foot of the bed with what can only be described as inadequate wire gauge.

I have updated this system this past year with new 8/2 marine wire, controller, and wired direct to the house batteries, with a harness also to allow manual change to the chassis batteries when on extended shore power time.

Today, I installed two new 100 Watt panels into this system for a total of 306 Watts to come closer to maximizing the capacity of the 30 amp controller installed in this solar system.

I had some concern about joining the new mono crystaline panels with the 17 year old SOLAREX poly crystaline panels, but my short test today appears to work as planned.

It apprears that SOLAREX is not a big name in panels anymore. May even be kuput??? but I did find this informative manual on line dated April 2000.

http://www.pendragon2.50webs.com/sol...ray-wiring.pdf

I will watch and test the preformance of this solar system over the next few weeks to make sure it is working as it should.

The CLIPPER now is equipped with 592 Watts SOLAR capacity on five independent systems that can be controlled manually or directed electronically from the cockpit.

I don't have a picture of the CLIPPER roof at this point but will post one later.

I have some details of the earlier wire upgrade here.

http://www.airforums.com/forums/f313...ml#post1283037

And some of the other SOLAR systems here.

http://www.airforums.com/forums/f313...ml#post1021953



Dave

[masseyfarm]

The good weather is here now and trying to get the Clipper polished up and ready to roll.

Many updates and changes have again been made over the winter.

To finish off the above post, here is an up-to-date picture of my solar collectors on the CLIPPER.

Dave

[masseyfarm]

I thought I understood the general basics of a simple solar system that would work on any RV, but times are a changing a little too fast for me to keep up. (I'm trying!)

The Schottky bypass diodes used in most cell-based solar panels serve as a protection mechanism that allows the panel to continue producing power when one of its cell strings is shaded or damaged. However, the characteristics of traditional diodes create energy losses that reduce the overall efficiency of a solar power system and, in some situations, may actually cause costly damage. To solve this problem, several manufacturers have introduced a new class of “active diodes” that use transistors to produce diode-like behavior, while allowing the solar panels they protect to operate with higher efficiency and better reliability. This article will explore the technology that underlies active diodes, look at the products currently on the market, and look at how they are changing the way solar panels are being designed and manufactured.

Read the complete article here.
Active Bypass Diodes Improve Solar Panel Efficiency - Energy Harvesting | DigiKey

On my quoted installation above, I tied in my old Solarex 2X53 poly panels with my new 2X100 mono panels and run them through my older Sunforce 30A controller that I had relocated closer to the battery bay. I added a Schottky diode to the Solarex panel output and everything seemed to work OK on test.

However, after reading this information on the new 'active bypass diodes' I am probably going to order new panels to replace the old Solarex and to up my solar capacity once again.

My 'todo' plan for this off season was to combine my panels in pairs of 24V and update my controllers to MPPT so this, combined with two new panels, should give me considerable increase in capacity and efficiency.

I don't think our smaller systems have any risk of fire, as explained in the article quoted, but our older panels may well be damaged if combined with newer high output panels and we would probably not readily notice the drop in performance if that did happen.

I will update this as parts and pieces come together.

Dave

[masseyfarm]

Another beauty of a day here on the west coast of the Salish Sea. If this is global warming, I think I like it.

Serviced the #2 battery bank "HOUSE BATTERY CIRCUIT" today as the Clipper has been tied to shore power since mid October. Last service was 10 months ago in April and my conscience was starting to bother me as I had intended to do this job in the late fall.

Pulled, cleaned, tested, topped off and rotated the 4 T105's and they will be good now until the fall.

All cells on these T105's, dated 2009, are testing high 1200's Specific Gravity with the HYDROMETER and show no sign of a problem. Very little distilled water needed to top them off. (NOTE: the 2 of 4 batteries in Series on the positive connections will always show a higher need for a water top off. This is why you should always rotate your batteries when they are removed for cleaning and testing.)

I had serviced the other two battery banks in Oct, so they are good till early May when we will be preparing the Clipper for the 2014 travel season.

When working with batteries, always were protective clothing and eye ware. Accidents happen too easily and one should take all precaution that personnel injury is not the result of lack of being unprepared.

If you have a solar system on your battery circuit, be sure this is disabled before working on the batteries in the confined space of the battery tray/bay. A small spark is all that is needed to create a big problem.


Dave

[masseyfarm]

Got to check out my House Batteries yesterday, as another long road trip is on the books for next month.

Its been awhile since I had pulled these Trojan T105's, and when I pulled them again yesterday, I was pleased that they were still in great shape, and testing reinforced my confidence that I will get at least another year out of them.
These Trojans were purchased in August 2009, so are now 6 years old. (The cost of batteries has gone up considerably this last year or so, with the Canadian $ taking a dive. Getting the maximum out of these batteries is my goal!)

Once again I will point out that your batteries should always be rotated when you service them. In a 4 battery bank, the two batteries on the positive side, (inverter and house panel circuits) will always be charged just a bit more than the two batteries on the negative side. I don't understand why that is, but it is proved repeatedly, every time I service and rotate my batteries. Also, the two batteries on the negative side will always require a bit more top off with distilled water. (this may because of the location of the battery bank on my CLIPPER, and the inside batteries may be running hotter than the outside batteries connected to Positive?)

I recommend the batteries be rotated in the X style, just like the old charts for rotating tires used to show.

Dave

[masseyfarm]

I keep having to re-learn this lesson over and over again.

Most solar controllers require that the battery be connected before you plug in the solar feed.

On my Clipper I have three solar controllers, one each for the 3 battery banks.

When I do battery pull, clean, maintenance, on these systems, I have to remember to reset my solar controllers. Otherwise they will not produce!

This only happens when the batteries are disconnected from the circuit.
On the CLIPPER, this does not apply when you use the battery disconnect switch for long term storage, as the solar panels are wired direct to the batteries and are not affected by the battery disconnect solenoid. (if your solar is connected to the circuit somewhere else, then it might be affected by your disconnect switch?)

Remember: When connecting a solar controller, always connect the battery first and then the solar feed.

Dave