Cook Station - Work Table project

 

Deck and cook station at dusk

The summer of 2020 was unusual because of the CCP Covid-19 virus

I probably should have posted this in July 2020, but I had not yet decided to expand the blog with more coverage of our winter and summer "lily pads". In 2021 I decided to include all of our camping experiences, so, here it is, better late than never as the saying goes. 

In July 2020 we spent more time at our summer "lily pad" which is a travel trailer at a campground in Michigan.  We did not travel very much due to covid restrictions. I took the opportunity to build  a cook station - work table on the site. It was a CCP Covid-19 project. We have made a number of improvements at this annual site, including adding a deck and wooden stairs. Because we do a lot of outside grilling and other cooking I had wanted to do this. With things "slow" and Gov. Whitless of Michigan playing tyrant, it seemed like an opportunity.  The Home Depot was open for business as was the Ace Hardware.

I didn't tell G what I was up to.  I told her I was building a "Mystery Project".  I had a budget and so  I made it simple. I made some sketches and from that got the dimensions of the 2x4s and three - 4 ft x 4 ft. x 3/8 inch exterior plywood. I sized it for 24 inch deep shelving top and bottom.  I would cut several 4x4 ft pieces of 3/8 plywood; I wanted minimal waste. I also needed deck screws of two sizes, sanding sealer for the plywood, and a quart of royal blue Rust-oleum gloss enamel. I used left-over Cabot gray solid wood stain with which to paint the frame.

Tools:

• Circular saw
• 3/8 inch electric drill
• Screw drivers
• Tape measure
• Square
• Pen
• Paint brush
• Note: All screws were drilled with a pilot hole. 

2x4 frame - on end, during assembly

After assembling the frame I set it in place to check overall fit and height. I then cut the shelving.  The photo was taken before the final small pieces were cut to make top and bottom shelves continuous. The top will be screwed into place and top and bottom rest on front to back 2x4 supports positioned at the seams. The bottom shelf will be set in place and be  removeable for winter.  The bottom shelf is three pieces and will be placed on top of the upper shelf during winter, then the grill folded and placed on that as well as an extra water hose. The topmost shelf ad contents are protected with a tarp during winter.  We did this for the the winter of 2020-2021 and it was fine in the Spring.  

Rough setup

I removed the shelves, which were simply set in place to check the fit.  I then set the frame on edge and stained it.  After staining the 2x4 frame will be rotated into the normal position. 

At this point G didn't have any idea of what it was, because she hadn't seen it set properly in position. I placed it at a corner of the deck and out of the way. After a coat of Minwax water-based sanding sealer on the shelves and a light sanding to knock off the shine I painted them with Rust-Oleum Royal Blue gloss enamel. The sanding sealer seals the grain and reduces the absorption of paint into the wood.  As a consequence less paint is used and there is a better, glossier finish:

Painting the shelving with Royal Blue enamel

I used deck screws to hold the 2x4 frame together. I used a shorter deck screw to hold the top shelves in position. All holes were pre-drilled before installing screws. The shelves cover the entire top and bottom surfaces. The 2x4 top frame provides a left and right "edge". 

After painting both sides of the shelves and the edges and allowing to dry overnight, I fasted the top shelf in place:

Using flush screws to hold the top shelf in place

I placed the fully assembled unit in place.  G said the really likes the height of the top surface, which is convenient for cooking.  It is of sufficient dimensions to facilitate serving and is near the 120VAC outlet on the side of the rig, which is necessary for the induction electric cooktop/ cast iron cooking. We purchased the propane BBQ in the photo from a camper who was selling their rig. It replaced the one that came with the Heartland travel trailer:

Cook station in position

After a full season of use (August 2020-2021), G says she really like it. We use it with the cast iron and inductive heater, toaster and so on.  I had considered a small cabinet on the lower shelf, but decided to build a separate cabinet and hang it from the side of the travel trailer, using the 3/8 inch tube shelf that held the Celano BBQ.

I also use it as a "work table" and it has been helpful.  

Original Material: Roadtrek210.Blogspot.com (c) 2021

Installing a Fresh Water Shutoff for Toilet

A few years ago I had a leak at the fresh water fitting of the toilet in the Roadtrek. That was primarily a nuisance because it is a wet bath and any water is contained within (unless it overwhelms the volume of the bath area and gray tank).

I solved that problem with a little TFE paste which is suitable for use on nylon fittings. I posted a video at the time about this.

Recently we had a slightly different and much more serious problem with a Thetford toilet. The fresh water valve failed to close. As is often true with "Murphy's Law" the problem occured at night, at the "most inopportune time". Gradually the toilet bowl filled and overflowed. We didn't hear it. In the middle of the night we discovered water was flowing out of the bathroom.

[Note: this post is not about the pluses or minuses of a Thetford. We like our "made in USA" Thetfords and wouldn't change them for anything. We have three rigs (two are Lily Pads and in all there are four Thetford toilets). In fact when we decided to change a toilet recently we went with a Thetford Aqua-Magic II. A contractor recommended another brand and we said "No". So I purchased and installed the toilet myself. $153.12, delivered price. ]

Now, unlike the toilet in a sticks n' bricks abode, RVs generally don't have a shutoff for the fresh water inlet to the toilet. So when we discovered we had a toilet fresh water issue I had to run outside and turn off all water to the rig. The water had to stay off until I could resolve the issue with the toilet. Of course, we could have turned on the fresh water pump when water was necessary but that too is risky. (Note: We did turn off the hot water heater "better safe than sorry" if the level in the heater fell.).

I decided that we needed a shutoff valve for the toilet. But that's easier said than done with such tight quarters. Not only is there limited space for a valve, there is also limited space to operate it.

I wanted something that would not require modification of the PEX piping.

I did find a very small valve with an easy slide "off-on" feature and decided to try it. I decided it would be easy to operate in the blind, by touch and without the ability to observe the valve, and it is!  Cost? $8.60. It is a "KES Shower Head Shut-Off Valve Ball Valve 1/2-Inch NPT BRASS Polished Chrome, KUS1140B"

Here are a few photos:

Toilet fresh water inlet - no valve.

Photo of the valve, to give an idea of the size

Suppliers photo of the valve.

Photo with valve installed. Fits well and works "wonderfully" and I don't have to see it to operate it. 

Here's a link to the earlier video about a dripping fresh water inlet to the toilet in the Roadtrek; this was solved with a little TFE paste applied to the threads:

Original material:  https://roadtrek210.blogspot.com/

Adding a Vent Fan to the Travel Trailer

Our travel trailer, which is one of our lily pads, has a vent in the bedroom, but no fan. We get afternoon sun and decided we'd like a roof fan in that room. The vent lid was showing some fatigue and so I decided to:

1. Replace the vent lid.
2. Add a vent cover so we can leave the vent lid open when the TT is unattended. This also affords additional protection to the lid, keeps birds from moving in, etc.
3. Add a fan inside the existing vent. I chose a fan which is rated 188CFM and  designed to retrofit within an existing 14 x 14 housing. 

I have three vents, so I needed three vent lids and three covers to replace all.

I found replacement vent lids for about $19 each delivered so I purchased enough to do all three vent lids. (I purchased two sets of two because the price was better than buying three singles. So I now have a spare which I can give to a neighbor).

I also purchased three vent covers; two white and one smoke tint for about $28 each. I purchased one fan kit for the existing vent. The fan was about $59.

Total price each set of vent lid and vent cover = $47 each set.
Vent fan = $58.50
Labor: $0 (I'm free)
Wire, etc $0, from my hardware box.

The vent lid replacement was very easy. I did need G inside to open and close it on request for testing of the new one. Tools were a phillips screwdriver and a needle nose pliers. To remove the lid I removed the crank handle, the inside screen and the two screws holding the mechanism in place. That allowed me to open it fully from the roof and slide the mechanism off of the old lid. I put the mechanism aside, bent the tabs which held the vent lid in place and slid the old lid off of the full width hinge.  I took the opportunity to clean the existing gasket and the screen.

The new lid went on in the reverse fashion. I slid it on and bent the tabs to keep it in place on the hinge. I then went inside the trailer and inserted the mechanism into the mating connector and screwed it in place. Then the screen went back and is held in place with two screws. Finally the crank handle was re-attached.   Time to do this per vent lid was less than 30 minutes.

Each vent cover went on in about 20-30 minutes.

Clean up about 30 minutes.

The  fan took a while because I had to drill an opening for two wires (I provided two #18 AWG per the fan instructions). I pulled the wires from an existing fixture to the fan location. I attached to the power of an existing light fixture for source of 12VDC. The fixture has two 1141 incandescent bulbs which draw a total of 3.06A. The fan draws 2.2A, I understand. With the dual fixture off, this circuit will draw less than the current draw of the bulbs. I may change this lighting fixture to LED bulbs to keep the current near the original 3A. The bedroom has three fixtures total with (4) 1141 12V bulbs, which is a total lighting load of 6.12A.

The fan is a 5 speed 3-forward and 2-reverse and is very quiet at the low and medium settings. We're quite pleased with it. 

Fan in box

Out of the box - CAUTION don't hang the fan from the wires during installation. According to the manufacturer doing so will damage the fan. 

Typical roof vent with the old vent lid removed. Note the mechanism hanging so  could remove the lid. I've cleaned the lid gasket. 

New vent lid installed

Wiring of existing lighting fixture -this will also supply the fan. CAUTION - make certain DC power is off before working on wiring. Note the interior of the vent lid is completely removed, so I could drill a hole and pull the new wires in the ceiling to the fan location. 

After drilling a hole I fished the new wiring through, attached it to the existing lighting. The meter is to verify polarity before wiring the fan. I did install a split grommet to protect the wiring where it goes through the thin aluminum sidewall of the opening. 

New fan completely installed. It went in place of the existing crank arm and the old screen. Most difficult part was aligning the new crank handle system to the existing lid mechanism while holding it up. G helped. The frame is the existing frame. CAUTION - Don't hang the fan from the wiring during installation. The manufacturer says that will damage the fan. 

Aligning the vent cover with the vent. Then after placing the cover in place I  marked the location of the brackets on the roof. No holes are required in the roof. The markings are to indicate where along the vent perimeter to place the brackets. 

Four brackets installed and ready to place the vent cover in position. This is before cleaning the old gasket.

Close up of cover bracket. It is held in place with a 3/16 screw with washer, lockwasher and nut. The arrow points to the alignment mark I made when I positioned the cover over the closed vent. The mark indicates where to place the bracket before drilling the hole in the side of the vent frame. 

Smoke vent cover over the new vent lid and fan

White vent cover over a new vent lid. I installed a total of three replacement vent lids and two vent covers.

Original material:  https://roadtrek210.blogspot.com/

AGM Batteries, Separator Operation, Charging and Voltmeter

Replacement Battery Separator

December 2019:
I installed a replacement battery separator and it works differently from the old one. See Note 5 in the Battery Separator section, below.

September 26, 2019:
After I installed the digital voltmeter I was able to more closely monitor the coach battery voltage as well as the operation of the separator. Earlier this year I purchased a replacement separator as a "spare".  The old separator seems to work inconsistently or intermittently. For example with the engine running and a 14V chassis battery voltage the separator will connect the chassis and coach batteries. But sometimes it does not!  Go figure. I've decided to install the spare and I'll provide an update after I do.

October 6:  I added information on "clicking" battery separators. This has been reported by owners.
To go to the section on the battery separator, click here: Click here to go to the post section about the battery separator.

June 26, 2019 added the SOC table for the AGM batteries in my 210P. Note, I replaced those batteries and the table for your batteries may differ.

July 3, 2019 clarified separator main and aux connections.
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Read the notes at the end before proceeding! This post is not a recommendation that owners perform their own electrical service. Working with electricity can be dangerous and can result in personal injury, or death or damage to your Roadtrek. 
Sorry if I created a scare, but one does have to be careful if tinkering with electrical systems. Mistakes can be very costly, or can result in personal injury.

My 2013 Roadtrek 210P has:

• 2 x 6 volt AGM coach batteries, about 220Ah
• Tripplite 750W Charger/inverter
• Battery Separator (bidirectional)
• LED 12V display (four round indicators)
• Digital 12V display (added by me)
• Onan generator (2800 watt)
• 50 watt solar panel, for charging the coach batteries (added by me)

2013 Roadtrek 210P display/switch panel
This is the display/switch panel on my 210P. In the photo the Onan generator is running and supplying 120VAC power. The Battery Disconnect is ON and this is indicated by the Battery On blue indicator. As a consequence the batteries are charging:

Charging the coach batteries
It is possible to charge the coach batteries:

• While on 120V "shore power"  and using the Tripplite
• While running the vehicle engine (see the Battery Separator section for limitations)
• By running the Onan generator and using the Tripplite.
• On solar

The limitations of the battery LED indicator

The LED indicator of the Roadtrek is a voltmeter which is somewhat limited. It indicates these battery conditions while the soft BATT button is pressed:

• L - Low
• F- Fair
• G- Good
• C- Charging

Note that the "C" indicator may be on even when the battery is discharging. This may occur shortly after disconnecting the coach from AC or stopping the vehicle engine. The reason is because the coach battery voltage is higher than normal 100% charge. This is what is called a battery "surface charge" and after a few minutes with a small DC load such as the slowly running roof fan, this charge will be dissipated and the true condition of the battery will be indicated. 

In the photo the Battery Disconnect switch BATT is ON as indicated by the illuminated "Battery ON" light. Pressing the Battery button displays the battery situation. The highest (rightmost) illuminated indicator displays the condition, which in the photo is a C for Charging:

Using a Voltmeter to Monitor the Battery Voltage
Monitoring the coach battery voltage is helpful for determining battery capacity. We may want to know how much energy is available in our coach batteries. A voltmeter is useful for doing this.

My Roadtrek didn't have a voltmeter, and the power/switch/display area isn't set up for one. However, there is a 12V "cigarette lighter" style receptacle in the rear overhead compartment, above the DVD player. Unplugging my powered antenna allows me to plug in a voltmeter to check the battery voltage:

12V receptacle

Here's a typical digital plug-in voltmeter. These can be purchased for as little as $7:

Plug-in Digital Voltmeter

What does that voltmeter display mean?
Here's a typical chart for AGM batteries. If we are aware of the voltage at the batteries, we have a rough idea of the "capacity" remaining. For example, if your voltmeter displays 12.50 volts, then you have used about 20% of the capacity or available energy in your batteries. However, I must note that it is not recommended to fully discharge batteries to 0%. That will ruin them.

You will have to decide how low you want to run your batteries. For longest life under moderate temperatures (77F is ideal) some recommend not dropping below 50%, or  about 12.05V.  Dropping to 20% (80% discharge) reduces battery life, but provides energy for a longer time. That's discharging to about 11.66V. Going lower will severely reduce battery life. Fully discharging AGM batteries can damage and ruin them. What does repeatedly discharge below 20% mean? It means severely reducing battery capacity, to the point the batteries cannot provide energy when disconnected from the Tripplite charger (when charging the battery).

Note that you might have poor batteries and be unaware. The 750W Tripplite inverter/charger can provide up to 45A (amperes) of charging current when on shore power. That's about 540 Watts. The Tripplite can not only charge batteries, but also power 12V DC appliances including lights, fan, propane furnace and so on when the Roadtrek is connected to shore power, even with poor batteries.

Having a voltmeter helps to determine just how long your batteries can support your RV when you are disconnected from AC power. For example, suppose you are running your fan, there are interior lights on, the occasional water pump, and your 3-way refrigerator is on propane (some 12V is used). After three hours the voltmeter indicates 12.5V. That means it took 3 hours to use about 20% of your battery capacity. Another 3 hours will use an additional 20% or more. That implies you'll have enough battery power to make it through the night (lights off, pump off and fan on).

This table is typical. Your AGM batteries may vary somewhat.

Typical AGM Battery Table

I replaced my AGM batteries and this is the SOC table provided by the manufacturer.  Your batteries may differ:

What does "reducing battery life" really mean?
AGM and gel lead-acid batteries are chemical devices. They generate electricity using lead plates or mats and an acid liquid. As we repeatedly discharge these batteries, certain deposits form inside them that reduces the capacity. Capacity is the ability to deliver full current for a certain amount of time before the voltage decreases below a useable level. As batteries age, that ability diminishes. For example, a new, fully charged battery can provide a specific amount of current for a specific length of time. Think of this as ability to run your fan, lights, DC for a propane refrigerator and a laptop. With new batteries, you might be able to do that all night. As the batteries age, the length of time decreases and you will find the batteries can no longer do so. And the lights will go out before dawn, whereas before they could be left on all night.

Alternative Voltmeter
I decided to add a digital voltmeter/ammeter. The advantage is I can monitor the amount of current being used and the digital meter provides me with a better idea of the "state of charge" and how much electrical energy might be available. The higher the current, the faster I will drain the batteries. The meter includes a Watt hour counter ("energy"), so I can roughly monitor how much energy is used overnight, should I choose to do so. The meter includes both high and low voltage alarms. This is detailed in another post:

The following data is according to the Tripplite 932768 manual for  750 Watt "PowerVerter DC-to-AC Inverter/Chargers", the Tripplite data sheet and a Roadtrek Manual

Charging the AGM batteries
The batteries can be charged from 120VAC. This is either via shore power or by running my Onan generator. One thing to keep in mind is to turn ON the battery disconnect switch before plugging the RV into AC power or starting the Onan generator. That is per Roadtrek recommendations for my RV.

How long can it take? If the batteries are depleted, it can take 12 hours or longer to fully charge the batteries.

Are there circumstances under which I can't charge the batteries? If  the battery voltage decreases to below 10.0V (+/- 3%, or somewhere between 9.7 and 10.3 volts) a low voltage cutoff will occur. The Tripplite inverter/charger will not charge the batteries if the battery terminal voltages fall that low.   If your vehicle engine is running, the battery may be charged via the standard alternator, if the battery separator allows (see the Battery Separator comments below). A underhood battery separator isolates the chassis battery from the coach batteries when the engine is not running.  However, batteries below 10.5 volts should be checked. They could be damaged.

How can I determine the state of charge? The Tripplite charger/inverter includes a display. However, it cannot be viewed without removing a cover.  Here is a photo with the cover removed. The Tripplite has two rows of LED indicators. One blinks green when on 120VAC and the Inverter switch is "OFF". Otherwise if on 120VAC and the Inverter switch is "ON" then it will be steady green. The switch is located on the Roadtrek display/switch panel near the side entry door. (see the first photo in this post, above).

The other Tripplite indicator goes from off to red to yellow to green depending upon the state of charge of the coach batteries. If charged more than 91% and on AC, one will be blinking green (on AC and inverter off) and the other will be steady green (91% or better charge).

The Tripplite is located in an interior compartment to the left and in front of the powered sofa when you are facing the rear of the RT. The Trippite has a fan and at times you will hear it running. However, there are exposed connectors/wiring so you do need to be careful. If you have any concerns, get a pro to do this.  DO NOT TOUCH ANYTHING.  After you have a pro demonstrate this to you, you can decide if you want to do it yourself in the future.

To reveal the Tripplite, lift up on the top wooden cover at the front and then slide it forward.

Tripplite and DC Electrical Compartment

The next photo is a close-up of the indicators on the Tripplite. The arrow points to a flashing green LED. That means the Tripplite is on AC with inverter OFF. The other indicator which is below the blue cable is the charging indicator. In the photo the bottom LED is green which according to the Tripplite manual indicates "battery capacity charging/discharging 91% - Full"

Here's the table from the Tripplite manual. There are a number of switches for configuring the Tripplite. These LEDs function with Switch in "AUTO/REMOTE" or “Charge  Only” Position. That is how my Roadtrek was delivered.

Approximate Battery Charge Level while charging and discharging (bottom indicator in the photo below):

• Green = 91% to Full Capacity (see the Tip below)
• Green and Yellow = 81%-90%
• Yellow = 61%-80%
• Yellow and Red = 41%-60%
• Red = 21% to 40%
• All three LEDs off = 1% to 20%
• Flashing Red = 0% (Inverter shutdown)

Tip: How can we determine the Battery Charge Level above 91%?  At about 91% the AC power of the Tripplite is about 10 amperes. At about 100% charge it will decrease to 2 to 4 amperes, assuming the inverter function is OFF. Monitoring the AC current consumption of the Tripplite can aid us in determining the battery charge level above 91%. I have a Progressive Industries EMS on my 210P and I can monitor the AC current consumption. If you have a similar arrangement, so can you. However, you do have to avoid running anything else in the coach to get a reliable reading from the AC draw of the coach.

Tripplite Fault Conditions (bottom indicator in the photo below):

• All three flashing slowly (1/2 second on, 1/2 second off) = Excessive discharge (inverter shutdown)
• All three flashing quickly (1/4 second on, 1/4 second off) = Overcharge (Charger shutdown)

The arrow in the photo points to the 120v power "Line green LED":

• Steady Green = Roadtrek inverter switch "ON" and the coach is on AC power (shore power or Onan generator)
• Flashing Green = Roadtrek inverter switch "OFF"
• Yellow = Roadtrek inverter switch "ON" and Coach battery providing power to 120V receptacles via the inverter.
• Red = Roadtrek inverter switch "ON" and power demanded of the inverter exceeds 100% load capacity

Tripplite LED Indicators

Tripplite Operation and Inverter Selector
The Tripplite has a 3-way slide switch for selecting the "Operating Mode". See the photo below:

Left Position - Auto/Remote
Center Position - DC OFF
Right Position - Charge Only

The "Auto Remote" position ensures that the connected equipment receives constant, uninterrupted AC power. It also permits the Inverter/Charger to be remotely monitored and controlled (in my 210P the Roadtrek inverter switch turns on and off the "inverter" operation if the Tripp-Lite slide switch is in this position).

The "DC OFF" position de-energizes the unit and connects AC OUT to AC IN. In my 210P this slide switch position disables the Roadtrek inverter selector.

The "CHARGE ONLY" setting allows the Tripplite to charge the batteries faster by turning off the inverter, which halts battery discharging.

Operation Switch in DC OFF position

Battery Separator.

Battery Separator - Bidirectional
The battery separator is under the vehicle hood. It controls the connection of the vehicle battery and the coach batteries. In my 210P the battery separator is a "bidirectional" 200A module with a relay for 12V systems. You may have a "unidirectional" model and if so, your battery separator operates differently than the following; for a unidirectional separator see the description in the next section.

The [bidirectional] separator monitors the engine ("Main") and coach ("Aux") batteries. The manual states "If either battery bank is above the connect threshold [13.2V], the relay [closes and] connects the two banks together. If either battery is below the disconnect threshold [12.8V] the unit will open the relay." However, once connected both batteries are at the same voltage. Opening the relay disconnects the engine and coach batteries, preventing the draining of both.  "The connect threshold is set to a nominal voltage of 13.2V, which would only be reached when the charging system is operating. The disconnect voltage is set to a nominal 12.8V, which is near the full charge resting voltage of the batteries. " 

I've monitored the separator and it seems to be intermittent. At times, if the coach battery voltage is less than 12.8V the engine battery will not charge the coach batteries because the separator disconnects if either battery bank is below that voltage. When this occurs, the battery must be charged via 120VAC (shore power or Onan generator). Or via solar. In other words, the battery separator in my Roadtrek doesn't seem to consistently connect my vehicle alternator to the coach battery if the engine battery is 14V and the coach battery is less than 12.8V. That's a coach battery that is 90% charged. See note 7.

According to the separator manufacturer:  The connect threshold is set to a nominal voltage of 13.2V, which would only be reached when the charging system is operating. This will cause the relay to close and the charging system can charge both banks of batteries. The disconnect voltage is set to a nominal 12.8V, which is near the full charge resting voltage of the batteries. This will cause the relay to be opened shortly after the engine is stopped, attempting to preserve 100% of the starting battery capacity for engine cranking."

Note 1: In my Roadtrek the terminal labelled "Aux" is connected to the coach batteries. The terminal labelled "Main" is connected to the chassis battery:

Note 2: The vehicle alternator (Main)  will connect to the coach batteries (Aux) if either the vehicle or coach batteries are above the "connect" threshold of about 13.2V, which is 100% charge. After connecting the batteries will remain connected unless one of the batteries falls below 12.8V. This was confirmed with a new battery separator. See Note 5.

Note 3 :  The separator includes a momentary "auxiliary start function".  The start terminal must see at least 3V* to activate. The auxiliary [coach] battery must read at least 10V*." "This is the input for engine start signal override. When power is applied to this input, the relay will close if the Aux. Battery [coach] is no less than 0.85 Volts below the Main battery [chassis]."  In my Roadtrek this is not used.

Note 4:  According to the separator manufacturer, "* = Typical voltage settings have a +/- 2% tolerance".

Note 5:  Update December 2019. I replaced the battery separator and the operation of the new one is different than the old one.  If either the coach or engine battery is above the "connect" voltage threshold of about 13.2 volts  then the separator connects both coach and engine batteries.  I've monitored this for several weeks and the operation is consistent. If the engine is running the engine battery voltage is about 14.0 volts and the separator connects the engine battery to the chassis battery. If the engine is not running and I connect the Roadtrek to shore power, the Tripplite charge voltage rises to above 13.4 V and the chassis batteries and Tripplite are connected to the engine battery. This is not the way the old separator operated and I can only assume that the old separator had a flaw or failure.

Separator Options
The separator includes some options, including a "start signal" but that is not wired on my Roadtrek. The "start signal input" is the input for engine start signal override. When power is applied to this input, the relay will close if the Aux. [coach] Battery is no less than 0.85 Volts below the Main [chassis] battery.


Where is the Separator located?
The battery separator is the device in the center of this photo with the two red rubber boots. In my Roadtrek the terminal on the right is labelled "Aux" and is connected to the coach batteries. The terminal on the left is labelled "Main" and is connected to the chassis battery:

Alternate Battery Separator - "Unidirectional" Type
The battery separator is under the vehicle hood, see the photo above. It controls the connection between the vehicle battery and the coach batteries. In my 210P the battery separator is a "bidirectional" 200A module with a relay for 12V systems.  The following is the description of a "unidirectional" model. These two models operate differently. You need to determine which you have in your RV.

The unidirectional separator is a 200A battery separator modules with an integrated relay for 12V systems. The separator monitors the engine and coach batteries. If the Main battery is above the connect threshold, the relay connects the two battery banks together. If the Main battery is below the disconnect threshold the separator will open the relay. You will have to determine which battery bank, Chassis or Coach is connected to the "Main" terminal.

The connect threshold is set to a nominal voltage of 13.2V, which would only be reached when the vehicle charging system is operating. This will cause the relay to close and the engine charging system can charge both the engine and coach batteries. The disconnect voltage is set to a nominal 12.8V, which is near the full charge resting voltage of the batteries. This will cause the relay to be opened shortly after the engine is stopped, attempting to preserve 100% of the starting battery capacity for engine cranking.

Battery Separator - Bidirectional - "Clicking"
The battery separator is under the vehicle hood, see the photo above.  From time to time, you might hear a "clicking" sound if your hood is open. That could be the relay of the separator opening or closing.

For a bidirectional separator the relay will close as noted above if the vehicle battery/alternator is above 13.2V and the coach batteries are above 12.8V. Or vice-versa. If either of these falls below 12.8V the relay will open. When the relay closes it connects the vehicle battery/alternator to the coach batteries and when it opens it disconnects or separates these batteries.

The bidirectional will connect the vehicle and coach battery systems if the coach rises about 13.2V and the vehicle is above 12.8V.

At rest, my vehicle battery is about 12.6V. Fully charged my coach batteries are about 13.2 volts after dissipating the "surface charge".

If one has a solar charging system for the coach batteries, it would be possible for intermittent connection of the two systems if the solar system rises above 13.2V and the engine battery is above 12.8V.  Depending upon load and sunlight conditions, if the coach battery falls below 12.8V or about 90%, then the separator relay will open, disconnecting the vehicle and coach batteries. If the sun comes out, or solar improves and the coach battery terminal voltage increases to above 13.2V (which will happen while charging) then the separator relay will close, connecting the two battery systems.  As the coach battery discharges, the terminal voltage will decrease. When sunlight increases, then the separator will again close the relay, "click" and the two battery systems will be connected.

Of course, a faulty separator may also close the relay at unexpected moments.

Solar.

Solar:
In 2014 I  added a 50-watt solar panel and a desulfating solar controller.  Using a 50-watt solar panel provides a maximum 4.17 amperes of charging current at 12V during peak sunlight conditions. That's more than sufficient for maintaining or topping off the batteries.

Notes:

1. This post is not a recommendation that owners perform their own electrical service. Working with electricity can be dangerous and can result in personal injury, or death or damage to your Roadtrek. 
2. This information is provided "As Is" and no warranty or claim of accuracy is given. Your Roadtrek and its equipment may be very different than what is portrayed here. 
3. Refer to the Roadtrek owners manual and the Tripplite Owner's Manual for complete information. 
4. The Tripplite inverter/charge includes 120V surge protection. In other words, outlets that are powered by the "invert" mode will have surge protection. Any others in the coach will not have any surge protection unless it is added. In my case, I have an electrical management system (EMS) on the shore power line. I don't have such a thing on the generator power output. 
5. For troubleshooting of the Tripplite, refer to the owners manual. 
6. This post is based on several other posts in this blog as well as recent social media posts by me. I'm providing this so I won't have to write this up again. 
7. My coach batteries exhibited difficulty at about 3 years. I suspect the problem was the model battery separator Roadtrek installed in my 210P. The separator won't connect the vehicle alternator to the coach batteries unless the coach batteries are at 100% charge. 
8. All info on the battery separator is per the manufacturer's data sheet. 

New Voltmeter-Ammeter-Wattmeter for AGM batteries - Part 2

New Ammeter-Voltmeter-Wattmeter

September 15, 2017: Added short video clip

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Short video:

New Ammeter-Voltmeter-Wattmeter

See Part 1 for the background information about the AGM batteries in my roadtrek 210P:

http://roadtrek210.blogspot.com/2017/08/new-voltmeter-ammeter-wattmeter-for-agm.html

Why add a digital voltmeter-ammeter?
The decision to add a digital meter was easy. Then I proceeded to decide upon the type of meter. I had seen a FMCA Roadtrek Chapter Cyberrally post about how someone added a digital meter and I wanted to do the same.

Finding a meter wasn't all that difficult. A meter which stored "Ampere Hours" would have been ideal, but I opted for a digital voltmeter-ammeter-wattmeter. The selected meter also included adjustable alarm points for high and low voltage. That would be useful for monitoring low battery voltage, or a point at which I wanted to pay closer attention to battery draw.

I ordered the meter ($15.99 at the time) with DC shunt. I wanted to connect it directly to the battery so I could monitor battery voltage even with the battery disconnect "off". A switch and protective fuse was necessary. The parts list included:

1. Meter with 100A shunt
2. Off-On switch
3. Case for meter and switch (Case dimensions: 5-1/2" x 3-1/8" x 1-1/2")
4. 25 ft. 4-conductor cable
5. Automotive fuse holder (I used a fuse from my kit)
6. Miscellaneous connectors.
7. Note: for details, see the parts list at end of this post. 

The most difficult part for me was determining where to mount the meter. I had decided that I wanted a surface mount case, so I could remove the meter in the future and leave no trace. Determining how to run the 4/C cable was also a bit of a challenge. I decided to route it behind the fiberglass side panel, into the coach along side the door, then behind the side panel and exiting just below the 120VAC/12VDC power distribution center. This required the temporary removal of the rear passenger seat. Lots of screws.

Passenger seat removed, propane furnace exposed

With the passenger seat removed, it was possible to remove the side panel, and pull the cable behind the panel. I pulled the cable from the battery compartment to the passenger seat area, and re-assembled the interior panel. I left a foot lomg "pigtail" for connecting the meter.

Cable at Passenger Seat

I then mounted the rear of the meter case to the wall. I used 3M Dual Lock™ General Purpose Reclosable Fasteners. Note the female electrical connectors on the cable from the battery compartment:

Base of Meter Case

I assembled the meter in the case. Marked the case and cut the opening with a Dremel tool and cutting wheel. I used connectors so I can remove this if necessary. The "female" end goes on the cable from the battery compartment. The "male" end is in the meter case. This is so there should not be any exposed live parts if I pull the meter, even if the fuse at the shunt is intact.

Meter and Off-On switch in case

This is the front of the meter and switch, assembled in the case:

Front of meter case with Off-On switch

I mounted the meter to the case mounted on the wall:

Meter case mounted to the wall

This is the shunt, which was supplied with the meter. For the meter I purchased the shunt is connected between the negative battery post and the negative conductor. The shunt is rated 100A/75mV. The shunt is actually a precision resistor and the higher the current flowing through it, the higher the voltage drop across it. The voltage drop is 75 millivolts at 100 amperes.

Shunt

The shunt was installed in accordance with the manufacturer's instructions. A right angle screwdriver is helpful for installing the wiring to the shunt (I used a phillips).

CAUTION - Installing the shunt requires removing the negative battery lead. Exercise great care not to short a tool from negative to the nearby positive terminal. DEATH OR INJURY CAN RESULT. Be sure there is no battery load when doing this procedure.

The shunt is connected directly to the negative battery post. The black (Negative) cable is connected to the other side of the shunt; the yellow arrow points to that connection. Three of the leads of the 4-conductor cable is connected to the shunt. The fourth conductor goes to the red (Positive) battery terminal.  I installed an automotive fuse between the positive battery terminal and the lead going to the meter. That is to protect the wire in the event of a short circuit

CAUTION - A properly sized fuse is necessary to protect the wire in the event of equipment failure or short circuit. Fire, damage,  injury or death can result from an unprotected circuit.

Shunt installation and automotive fuse on positive battery terminal

With the installation complete I threw the "Off-On" switch to the "On" position.

I checked the display using a precision digital VOM. I measured the mV at the shunt and calculated the meter reading. The meter agreed.

Meter Setup
The meter has alarm points and some options:

1. Set backlight off or on. The default is "on".
2. Set voltage alarm threshold. The meter includes both "high" and "low" voltage alarms. These are set independently. The presence of an alarm flashes the backlight alternating "off" and "on". I set the low voltage alarm at the 50% DoD level for my coach batteries.
3. Set the measuring range. This meter will work with a 50A/75mV shunt or a 100A/75mV shunt. I set this to match the installed shunt, which is 100A/75mV.
4. Energy reset. The meter will accumulate and store kilo-watt hours (kWh). This value can be reset to zero.  

Meter Limitations
The meter is a DC meter. This means that the ammeter measurement is polarity sensitive. The meter as connected can only measure discharge current from the battery across the shunt. When charging the meter displays 0.00 amperes. However, by reversing the connections it is possible to measure charging current. I tried this and it works.

It was interesting to watch the Tripplite inverter/charger step through the charging levels. I may add a DPDT switch for this purpose, but it is completely optional. I've monitored the Tripplite by watching the AC current; as the Tripplite throttles back the AC current decreases. However, other 120VAC loads will mask that.  It is also possible to pull the compartment cover over the Tripplite and observe the charge state LEDs:

Green = Full Charge

Detailed Parts list, my cost $36.45 plus tax and any shipping:

1. MICTUNING DC 6.5-100V 0-100A LCD Digital Display Ammeter Voltmeter Multimeter Volt Watt Power Energy Meter Blue with 100A/75mV Shunt, Part No. MIC-DVG-015.
2. Serpac black plastic case, model 151i, BK.
3. Rocker switch, Philmore No. 30-882.
4. 4-conductor shielded cable, 24 AWG. (Use #22-24 AWG; smaller AWG is easier to pull).
5. Insulated terminal disconnects, male and female (from toolbox, not included in price total).
6. Fuse and fuseholder to protect the wire from the meter to the (+) positive battery terminal. Size of the fuse is determined by the size of the wire.