The Conversion of my 86 Crown Supercoach

My template for the unistrut in the Crown

Since the weather is pretty crappy outside (lots of much needed rain) I am inside. I am taking that time to document more of my design. I am sharing some of the design, both to help others and maybe get constructive input about what I am doing.


First is a drawing of my template for mounting the Unistrut at the top of the sides of the Crown. I took the template and traced the outline on a page of my notebook. Additionally I documented how it is used. I made this one out of aluminum.


While I used Unistrut to frame everything in my Crowns, someone else could easily use wood in a similar way.
 

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I finally documented my wiring plan for the Crown. I ended up getting some different breakers to accommodate this but that is minor. I ended up with the right number of circuits. I have one plan for the AC wiring and another for the DC wiring. This post documents the AC wiring plan.


In the drawing of the electrical panel plan, there are two sets of mechanically linked breakers. The upper set provides for switching between outside (shore) power or internal generator power, while the lower set provides for switching between the power supplied from the upper set, or from the 3000 watt sine wave inverter.


There are four circuits that only have power when power is supplied from outside or internal generator. The lower circuits have power from any of the three sources (outside, generator or inverter).


I modified an siemans panel by physically attaching two smaller breaker assemblies together in one box. One could take a larger box and electrically isolate an upper and lower half by cutting the two bus bars inside.


The circuits that only get power from outside or generator are:
Washing machine - I don't plan on doing laundry while going down the road.

Clothes Dryer - see above

RV charger - We don't want the batteries supplying power to charge batteries.

Engine heater - I takes 1200 - 1500 watts and would need to run for an hour or more to be effective. That is a lot to pull from batteries.
 

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Crown Bus - AC wiring plan

The next drawing shows all the AC circuits I plan to install in the Crown. The physical placement of the circuits is related to how they show in the drawing. Basically I planned the electrical as left or right side of the bus, and circuits by room. One circuit does not go into a room but underfloor to the engine heater. When you have a diesel without glow plugs, you NEED the engine heater.


The current rating of each circuit is based on the expected usage on that circuit. For instance in the kitchen, the outlet on the left side will supply power to a 1000 watt microwave. On the right side of the kitchen, the outlet will see little use. On the left side of the front room, the outlet will supply power to a laptop or cellphone charger, while on the right side of the front room, that circuit provides power to a 55" TV and a large stereo system at the same time.


All of the wiring is above the floor, with the electrical panel to the rear of the water closet, in the hallway. Any wiring going to the left side of the bus is carried overhead in Unistrut channels. I am not sharing water lines and electrical wiring in the same channel. Some of the DC wiring will share a channel with AC wiring, as practiced used in military aircraft.
 
The picture did not post so here it is
 

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A small correction: The engine heater circuit will go through the floor to reach the heater on the side of the engine block. The positive cable to the battery bank will also go through the floor to the trunk.
 
Time for another update to my conversion:


I completed the hold down clamps for the refrigerator. The refrigerator sets on two edge supports that keep the rollers and levelers on the bottom of the fridge just off the floor. At the top of the fridge are two clamps that hold the fridge in place so it doesn't move around when making turns and stops, etc. Later an additional piece of steel will be attached over the front of the fridge to construct a small cabinet for storage.


The main inverter and secondary inverter are mounted but not yet connected.



The posted picture of the main inverter was taken before welding the mounting bars to the Unistrut.


I have installed two runs of the main DC buss, going from the second alternator to the secondary inverter, and from the second alternator to where the terminal block will be installed behind the main inverter. Both runs pass through the floor above the engine and adjacent to the front of the fresh water tank. They are secured to the Unistrut framework around the fridge, where the secondary inverter run passes up to the inverter mounted adjacent to the fridge, while the run from the alternator to terminal block passes along the side of the bus, secured to the steel body framework of the bus to just past the water closet where the terminal block will go.



The terminal block will have three terminals interconnected with a bus bar. Since I will have five connections in one place, this approach has only two connections to any terminal on the block.


I don't like having 3 or 4 connections on one terminal as that could lead to loosening connections from vibration, and probable increased resistance. As there will be un-fused substantial current flow possible at these terminals the terminal block will be installed inside of a plastic enclosure.



I have completed installation of the drain plumbing for the washing machine and connected it to the main drain pipe. The run of drain plumbing for the washing machine includes a check valve type vent. The drain connection for the washing machine has since been secured to the Unistrut with an exhaust pipe clamp.



I have installed the drain plumbing for the shower and connected it to the main drain pipe also. I still need to fabricate the securing bracket for the shower drain at the trap area.


I have been installing some of the propane plumbing in and under the bus. I have one length of pipe to install under the floor that completes the underfloor portion. I will post some pictures of the underfloor drain and propane plumbing possibly tomorrow to hopefully make all of my narrative clearer. I was laying under the bus this evening and realized how busy it is under the bus. (kind of reminds me of the inside of the wheel wells of a B52) I can tell you there is no extra room under the Crown where the bus batteries are. I have been squeezing myself in there to install the propane plumbing. But with one piece to go under the floor I can tolerate a little more time under there. My approach is to have secure mounting of the whole of the propane system so that none of the connections will get loose and leak.


My first AC circuit to install will be for the engine heater. The floor pass through is with the other (now six total) pass through connections:


1) Generator power to electrical panel.
2) Remote control/monitoring wiring for the generator.
3) Outside (shore) power to the electrical panel.
4) Propane plumbing sourced at the regulator connected to the underfloor tank.
5) The AC circuit connecting to the engine heater.
6) The drain plumbing for the washing machine.


This will get an updated picture when I finish the heater circuit.
A lot of things pass through in a smallish area but all of this will be behind the wall when all is done.


Next in the schedule is de-installing the range to finish the propane plumbing run and install DC wiring and thermostat wiring for the furnace. Once that task is completed I can have heat in the bus.


I will be installing some more lengths of Unistrut and conduit to provide a path for more AC wiring.


It appears that some of the "wiring trays" I create will have some AC and DC wiring alongside each other, But looking at the my power panel from a C2 military aircraft, I realize it has both 115 VAC and 28 VDC wiring in one cable of wiring, so I think that will be safe to do. What will be important for the adjacent circuits is that the AC and DC wiring needs to be distinctly different so that one never gets confused between the two.
 

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Some additional pictures of the washing machine plumbing:






The conduit for the engine heater circuit is between the propane pipe and the washing machine drain pipe. (not in picture)
 

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This posting documents my fresh water system in the bus. It is not completed yet but I am posting what it will be. It will be simple to operate. When connected to outside (shore) water all of the sinks, shower, toilet work like home. When you need to fill up the fresh water tank just opening one ball valve fills it. A second ball valve allow the system to be drained. The check valve is redundant since the pump has a check valve.


When dry camping, just turning on the pump is required to make the system work.


I am using two colors of PEX, red for hot, blue for cold.


I am using metal "forms" to make 90 degree bends in the PEX for the sinks. I already used shark bite 90 degree fittings for the shower but I may re-work those connections using the "forms". Less connections is better. I have lots of extra PEX anyways. The outlet from the drain valve will be the only part of the system going through the floor and that only has water in it when draining the system.


The runs of PEX are being mounted to the Unistrut to support them.



All of the plumbing is in one area of the bus. The runs of PEX for the shower cross overhead in Unistrut. I am keeping the plumbing inside of insulated space to avoid frozen pipes. (lesson learned in the "old Crown")


When filling the tank, one does have to keep an eye on it, but being the tank is translucent you can tell how full it is.
 

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This post documents the main DC buss in the "new Crown". I am trying to use the kiss principal in my designs.


The main DC buss has to take input power from four different sources:


1) The second alternator mounted to the engine (already installed). (up to 250 amps)
2) The solar Array on the roof (not installed). (up to about 70 amps)
3) The RV charger. (already installed) (up to 65 amps)
4) The batteries. (not installed) (up to 300 amps?)

The DC system will provide power to three loads:

1) An array of DC circuit breakers to feed lighting, heating.
2) The batteries for charging.
3) Two inverters.

To do this, I am using 2/0 gauge cable salvaged from the parts Crown battery cables. I ended up with two sets of battery cables 11 feet long for a total of 44 feet.

The highest expected current draw is when running air conditioning from the inverter, along with the refrigerator. (about 200 - 220 amps) Since the current flow required to do this would drain batteries fast I would only use the air when driving.

When driving most of the current is from the alternator. When parked most of the power is from the batteries and/or solar (in daylight). To make this work and not have two many connections at a single point, a terminal bus is the way I am doing it. It will be fabricated from machinable plastic and bolts and nuts and a buss bar made from two layers of flattened copper tubing.

The terminal block will be enclosed in a 6" x 6" plastic enclosure. The terminal block will be installed adjacent to the primary inverter since that is the largest load (and there is space there).

The 2/0 gauge cable is mostly run along the inside of the side of the bus, and attached with clamps. The forward run goes from the alternator, through the floor, along the side to the terminal block. The rearward run goes from the terminal block along the wall through the floor near the rear of the bus into the trunk, where the batteries will be.

Additional runs connect the RV charger, the solar charge controller, and main feed to the DC circuit breaker panel to the terminal block.
 

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Today I got close to a milestone in the conversion of the "new Crown". With the exception of two additional mounts and connecting the primary furnace to the gas line, I am basically done installing the propane plumbing in the bus. I was able to complete installing all of the gas line under the bus and continue with the portion that serves the left side of the bus (primary furnace and gas range).


Attached are some pictures of it:


The first image shows the plumbing behind the gas range. The second image show the plumbing coming up through the floor, going to the left side wall of the bus. The run is secured in two places. In the third image, the portion that supplies gas to the range is visible, as well as the clamp securing the line where it tees off to feed the range. The line continues forward and makes a 90 degree turn inboard in the bus. That portion can be seen in the first image. The last portion will be secured two places, similar to the mounts securing the first part of the run after it comes through the floor. The second image also show the gas shutoff valve. All appliances have a shutoff for safety. The range and furnace share a shutoff as access to the line supplying the furnace is difficult to reach. I will try to get some more images of the propane plumbing underneath the bus to share.
 

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Today I finished mounting the propane plumbing above the floor on the left side of the bus. This plumbing supplies gas to the gas range and the furnace. To complete this portion of the plumbing required the de-installation of the gas range, the countertop and cabinetry on the left side of the kitchen. I installed the last section of black steel pipe and installed the mounting clamps between the pipe and the pieces of Unistrut. While clamped to the pipe I welded the mounts to the Unistrut, thus securing the pipe in place. I also added another short piece of strut above the existing clamp on the run supplying gas to the range. This was done to meet a requirement of the NFP 1192 specification of requiring supporting mounts within 6 inches of the end of a run.


Reading up on NFP 1192 I found that the spec doesn't allow for running gas plumbing inside walls or partitions. I have a short run of pipe that will be inside a wall for the water closet. My understanding is that this is to prevent an undetected buildup of gas inside of a wall that could lead to an explosion. My approach is to leave an escape route for any leaking gas so that it would be detectable and not contained.



I encourage a response from other skoolie folks regarding their opinion about this.



I will also comply with the requirements to support the plumbing at 4 foot intervals, and of course use the yellow tape at all connections. There are no left/right couplings or elbows used.


I still have one more mount underfloor to install to comply the the support each 4 feet of the pipe requirement.



A picture of the plumbing run in question is attached. The pipe on the right is the propane run. The other three are conduit for wiring. The space behind the strut on the right side of the picture will remain open. Since this picture was taken a run of drain plumbing and a run of conduit has been added to the right of the pipe. Note: this picture is taken looking at the right side of the bus inside the water closet.



Attached is pictures of my work today.
 

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Today I finished mounting the propane plumbing above the floor on the left side of the bus. This plumbing supplies gas to the gas range and the furnace. To complete this portion of the plumbing required the de-installation of the gas range, the countertop and cabinetry on the left side of the kitchen. I installed the last section of black steel pipe and installed the mounting clamps between the pipe and the pieces of Unistrut. While clamped to the pipe I welded the mounts to the Unistrut, thus securing the pipe in place. I also added another short piece of strut above the existing clamp on the run supplying gas to the range. This was done to meet a requirement of the NFP 1192 specification of requiring supporting mounts within 6 inches of the end of a run.


Reading up on NFP 1192 I found that the spec doesn't allow for running gas plumbing inside walls or partitions. I have a short run of pipe that will be inside a wall for the water closet. My understanding is that this is to prevent an undetected buildup of gas inside of a wall that could lead to an explosion. My approach is to leave an escape route for any leaking gas so that it would be detectable and not contained.



I encourage a response from other skoolie folks regarding their opinion about this.



I will also comply with the requirements to support the plumbing at 4 foot intervals, and of course use the yellow tape at all connections. There are no left/right couplings or elbows used.


I still have one more mount underfloor to install to comply the the support each 4 feet of the pipe requirement.



A picture of the plumbing run in question is attached. The pipe on the right is the propane run. The other three are conduit for wiring. The space behind the strut on the right side of the picture will remain open. Since this picture was taken a run of drain plumbing and a run of conduit has been added to the right of the pipe. Note: this picture is taken looking at the right side of the bus inside the water closet.



Attached is pictures of my work today.


You're doing a really nice job, those gas lines are great. If you swap out those conduit fittings for "LL" you would have the cover plate accessible. Hold the fitting like a gun "LL" is left "LB" is back (what you're using) and "LR" is right. That'll make your life a little easier in the future.
Carry on, sorry to interrupt :wink1:
 
Today I performed a successful leakdown test of my propane plumbing in the "new Crown".


The other day I performed the test and ended up blasting the system, which the 3 psi gauge did not like. My first attempt found leakage. Because of that I dismantled the portion of the plumbing inside the left side of the bus, cleaning the yellow tape from all the threads and re-assembling it all using the yellow paste instead.
For today's test I also used a pump bottle of "tire soap" I got from the local mechanic. I initially isolated the left and right sides of the plumbing by closing the valve located where the pipe passes through the floor to supply the main furnace and the gas range. I found leakage and when I opened the closed valve the pressure went up (I started the test pressurizing the whole system). This indicated to me that I had a leak in the portion of the system I had just re-assembled. Using the tire soap I checked all of the joints and the schreader valve that I used to fill the system with air. The only leak was the schreader valve itself. I also removed the cover from the pressure gauge and checked it for leaks, and found none there.
I took one of the valve stem caps off the bus and screwed it as finger tight as I could get it.
After 10 minutes no leakdown. I went home for a bit came back to town picked up dinner and checked the pressure in the system. After 2 hours, still no leakdown.
Attached are a couple pictures of the system with test gauge installed. Note: when I pressurized the system it started out just under 3 psi.


The pictures are taken after 2 hours of pressurization.


A shutoff valve will replace the brass T fitting when I re-install the gas range.

When the appliances are connected up to the plumbing I will repeat the test and verify that the appliances and their connections do not leak either.
 

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The conversion of my 86 Crown Supercoach

It is time for an update on the "new Crown".
Since my last post on my project the following has been done:
1) Fabricated the countertop for the right side of the bus kitchen. The right side of the bus has the kitchen sink.

A) Cutout the hole for the kitchen sink, and the faucet.
1) Discovered the faucet (made for use in a house not an RV) was not designed for a countertop 1 1/2" thick. Since I had already made the mounting holes I had to come up with a way to make the holes larger but not all the way through. My approach was to take the plug the hole saw made when cutting the first hole, place it back on the pilot drill bit with a larger hole saw cutter and go at it. It worked. The hole wasn't perfectly centered but close enough. The countertops are Acacia wood which is soft and kind of spongy so a screw driver and hammer removed the donought, so the faucets would mount.
2) Fabricated the lavatory sink countertop.
A) same as the kitchen sink for the faucet.
3) Applied clear polyurethane to all three countertops - 2 kitchen one lavatory.


Installed the sinks and faucets and temp mounted the countertops.


Installed the fresh water tank, finally securing it with an H shaped frame on the top secured to lengths of all thread.


Fabricated the rest of the fresh water plumbing, including the connection to outside water through the side of the bus. Per the design I previously posted for my water system filling the fresh water tank is accomplished by opening a ball valve while connected to outside water.
I will be making an additional connection to the fresh water tank to facilitate filling it with RV antifreeze before winter. That will involve cutting the opening at the sealed threaded (not yet) hole and installing a plug.
The water pump is mounted to the floor under the lavatory sink.


I installed the rest of the drain plumbing. I estimated where to make the throughfloor hole for sink drain plumbing and got it on the money. It was my plan for both sinks to be adjacent to each other to keep plumbing simple.


I finally tested the small inverter that I installed for the fridge and CPAP and it is no good. It reads the input voltage OK but zero output. Another one is on the way.


The main furnace is installed but not wired yet. After a good test of the propane plumbing (after failing the leak test first time, and subsequent re-work) I have connected up the main furnace to the propane system.



I have got all five solar panels installed on the roof. They cannot be seen from the ground. Next for the solar is the wiring.


I disassembled part of the bed and lifted it up to facilitate installation of the rear half of the main DC bus. Since the batteries go in the trunk, the main bus cable needs to get into the trunk. I attempted to push the cable through the rounded floor channel (in Crowns where the floor meets the wall (side) there is a rounded transition made of steel covered with rubber), and found an obstruction trying to push past the wheel wells. Tomorrow I continue with the main DC buss effort.


After I complete the gate valve on the black tank, then onto wiring of the solar array.


see the cross section of the Crowns floor - 1 1/2" thick.
 

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The conversion of my 86 Crown Supercoach

I forgot to post about the generator in my bus.
last year I had intermittent problems with the Onan 6.5DKD genset I installed in the Crown. I ended up replacing a relay but that didn't fix it, installed a jumper wire across the circuit board inside the control head and it seemed to work OK afterwards. Recently I decided to finish up with my planned upgrade to it, namely re-configuring it to use 2 30 amp breakers instead of one 30 amp and one 20 amp.
Onan offered this genset with different configurations, one of them being with one leg with a 30 amp breaker and the other leg with a 20 amp breaker.
another configuration was a 30 amp breaker on each leg.
Mine came with the 30 amp - 20 amp configuration.
I found the 30 amp dual breaker on eBay last year and got it.


I then cut out part of the metal mounting plate for the breaker, welded in a piece of sheet metal to fill the hole, and cut the proper opening for the dual 30 amp beakers.


I replaced the 30 amp single breaker, and 20 amp single breaker with the 30 amp dual breaker, wited them in place and re-assembled the genset. It worked OK several days, but twice it went to start it and it would not turn over.


Today I tried the remote start. I had already fabricated and installed a remote control cable for the genset. I re-connected the cable, touched the 12 VDC wire (pin 3) to pin 5 (start) and it turned over. I touched pins 3 -4 for 10 seconds then pins 4-5 and she started fine. Looks like the start switch in the control head is shot.
 
Looking good. We used to use a slightly higher pressure (10-15 psi) for testing, primarily because it's easier to detect a leak. Final testing could then be done according to the NFP. I'm glad you got it sorted. I have a minor suggestion regarding your conduits... an "LL" condulet fitting would put the covers out where they are far more accessible. For clarification...hold the fitting like a pistol ..LL, LB, LR. I really like your attention to detail and ingenuity. It's inspiring : -)
 
The conversion of my 86 Crown Supercoach

I reached another milestone with the "new Crown":


I completed the main DC bus and successfully tested it.


Since the main DC bus needed to have six different connections, I built a junction box to accomplish that. I used a 6" x 6" x 4" (1/4" thick plastic box to house everything. I used four terminals for six connections. To construct the terminal block I used machinable plastic. The bus bar is made from two layers of flattened copper tubing.
I placed a battery monitoring module inside the box, along with a hall effect sensor that monitors current flow to/from the batteries.



The expected current flow will reach up to 250 Amps from the alternator and > 250 Amps from the batteries so I used the battery cables from a Crown bus that I parted out years ago (sometimes it pays to keep things). The battery cables connect the second alternator and the batteries to the junction box. The batteries are located in the trunk of the Crown. To provide the best possible negative/ground path for the batteries, I made the connection point to one of the structural elements in the Crown's body, a steel piece that run most of the length of the bus where the sides intersect with the floor. The seats attached to that piece, and the vertical ribs that frame the sides are welded to it. (see image of the cables where thay pass through the floor into the trunk)


The solar is not yet wired up so I wasn't able to test that yet.


The current connections to the bus are:


1. The second alternator.


2. The small inverter. (400 Watts)



3. The large inverter. (3000 Watts)


4. The RV battery charger. (65 Amps)


5. One of two batteries. (deep cycle type 31's)


The cable is run for the output of the bus (lights, etc) but not yet connected to any loads. The cable is run to be connected to the solar charge controller but the charge controller is not yet installed.


To test my work, I connected the battery to the main DC bus with the engine not running, the RV charger off and both inverters off, and the Onan 6.5DKD genset running and on-line through the main electrical panel.



1. I measured the bus voltage at the output terminals of the RV charger and found the expected 12.8 VDC.

2. I applied power to the RV charger and found the voltage increased to about 13.5 VDC.
3. I turned off the RV charger and started the bus engine. The voltage went up to 14.6 VDC at the RV charger connections.

4. I turned on the 400 Watt inverter and it came up but no load was applied.
5. I turned on the 3000 Watt inverter using the push button on its front and it came up. I connected a 5100 lumen LED light to the inverter and it came on.
6. I checked the battery voltage at the battery terminals and verified it matched the reading found at the RV charger.
7. With the Crown's engine running I turned on the RV charger and verified no smoke and found no change in voltage (which I expected).
8. I shut down the Crown's engine and the Onan genset and measured the voltage at the battery terminals and found 12.8 VDC.
9. I setup the meter to measure current flow for parasitic loss. After a momentary surge of current, the current flow stabilized at 17ma.



See attached pictures:


Safety is a major design consideration in how I design the various systems in the bus, so only +12 VDC is present in the junction box, as it is unfused.
 

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I have a question for skoolies with experience in running a Magic Chef refrigerator 10.1 cubic ft model HDMR1000WE from an inverter:
My understanding was that the unit used 165 watts running, with a surge at startup.


The first inverter was a 300 watt true sine wave model out of China, sold under multiple brand names on eBay. The result was instant failure on first power up.


The second inverter is a Cobra brand inverter rated at 400 watts. Upon power up it tries to run the fridge for about 2 seconds and then set its over-current alarm.


The third inverter is a VertaMax Power inverter rated for 500 watts with a 1000 Watt surge.
With this inverter it runs about 3 seconds (you can hear the compressor start and run for about 1 second) then sets its over-current alarm.


I went to the Home Depot website and went through about 220 of the 600+ questions about the fridge and found varying answers about how much power the unit draws. The manufacturer says about 1.3 or 1.4 amps running with watt ratings from 130 - 140 Watts.
As for surge ratings based on the Q and A listings, it draws a surge current about 5 amps or 600 Watts.


Also I ran it for several minutes from my 3000 Watt sine wave inverter with no issues.


It appears that either that fridge draws more current than the manufacturer states OR these inverters are not capable of the power ratings advertised.



I was going to go the route of a lower powered inverter for nighttime usage for efficiency when running a fridge and CPAP.


Any ideas?


I plan to attempt to measure current flow for the fridge tomorrow.
 
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I believe I now have an answer as to why the 400 Watt and 500 Watt inverters could not power my referigerator.
Using an extension cord with the wires separated to allow the use of a clip-on ammeter I powered the fridge up using the 3000 Watt inverter and measured the current flow using the ability of the meter to show peak current flow.
I measured 9. Amps in a surge of current flow. 9.2 amps at 115 volts AC = 1058 watts.
The 400 Watt inverter is rated for an 800 Watt surge, so a nogo is expected there.
The 500 Watt inverter is rated for a 1000 Watt surge, so that one cannot handle the load either.
I did not expect a surge that large for a referigerator the the manufacturer says uses 1.4 Amps running.
I now think a 600 Watt inverter would probably work, but that leaves a small margin for error. Probably 800 to a 1000 watts is a reasonable starting point but the law of diminishing returns is starting to come into play.



Is the efficiency of running a 1000 Watt sine wave inverter running a device that has asurge current of 9 Amps and a running load of 1.4 Amps enough to justify the extra wiring and hardware over just running the 3000 watt inverter?


I may use the 400 Watt inverter for my CPAP, or just use the DC to DC converter made to run the CPAP. The DC to DC converter that plugs into a 12 volt socket (cig lighter) may be the most efficient way to address this.


Of course the 400 Watt inverter will be useful to charge phones, run a laptop in the bedroom, etc.
 
The conversion of my 86 Crown Supercoach

Another update on the Crown:
I finished the installation of the rack mounts for the various electrical panels that will contain the electrical system monitors and DC circuit breakers. This ended up producing one end of the solar charge controller mounts. With the completion of the charge controller mounts and subsequent mounting of the charge controller, I connected the battery outputs of the controller to the main DC bus and ground. Now I have an easy place to check RV battery voltage.


Today finished fabrication and installation of the black tank gate valve mount. The Black water tank is not real thick so the weight of the gate valve and any hose connections to it would stress the end of the tank where the drain is. I fabricated a mounting bracket that provides stiffening and support to the gate valve connection. I also installed the flange that connects the gate valve to a waste hose. This completes all of the drain plumbing. I need to cut the opening at the right upper rear of the fresh water tank to provide a means to pour the pink RV anti-freeze into the tank. My plumbing design does not use a second connection on the side of the bus to fill the fresh water tank, but instead a valve in the plumbing allow the tank to be filled through the main outside connection that supplies all of the plumbing system when connected to outside water sources.
With that small exception all other plumbing is complete.


The battery tray is the next project. It will hold 4 type 31 batteries, and be mounted in the Crown's trunk.


I am considering a third inverter in the bedroom at the rear of the bus. This one will only need to run the CPAP and maybe the occasional laptop.


See the attached pictures:
 

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  • solar charge controller 1.jpg
    solar charge controller 1.jpg
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  • solar charge controller 2.jpg
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  • gate valve mount final.jpg
    gate valve mount final.jpg
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