New Alt-Power Board

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The last setup had inverters & wiring dangling off a piece of plywood bolted to the wall.  It was very functional, and made reconfiguration rather easy.  Perfect for a prototype system.  Now I know what works, the system will have the wiring inside shallow cabinets, and the inverters, switches, gauges, and indicators, mounted to the cabinet doors.  This technique is common in the boating community, but found a good example on YouTube by OBXSOLWIND.  One of his videos showing his Alt-Power board is at this link

Functional, but messy looking.


The assembly for the cabinet began at the old house.  I used the back of my truck as a workbench.

I used a Kreg Jig to assemble the sides to the tops of the cabinets, and the cabinet frame to the back panel.  This is a very quick, clean, and strong method of assembly.

The sides of the cabinet are 1 x 4.  This should provide enough cabinet depth to hide all the wiring, fuses, etc.  Inverters produce heat, which is why they'll be mounted to outside of the cabinet doors, rather than hidden inside.  The Kreg Jig made the pocket holes to screw the pieces together.  These holes are inside the cabinet, hidden from view when the project is finished.

Once the cabinet frame was assembled, it was placed on the cabinet back, a piece of 3/4" plywood.  I left the back slightly larger than the frame, allowing a power strip to be mounted under the cabinet.

The frame was attached to the back by using more pocket holes & screws.

With the structure standing up, you can see it's larger than the original panel in the background.  Two pictures were stitched together, giving the illusion of a slight bow in the vertical pieces of the cabinet frame. They are actually very straight.  And now they are secured to the 3/4" plywood back plate in multiple locations, they'll stay that way.

Two stringers were added.  Gives strength to the box plus divides each section.  One section will be for DC loads, one for AC loads, and one for the battery bus bars.

No need for a fancy assembly table.  This nifty saw horse pivots to form a free standing X, or flat for storage.

Even without the doors yet, this thing is heavy!  I will build it, finish it, then take it apart so I have half a chance of lifting it up to a French cleat on the wall.  After it's secure on the wall, then I'll re-hang the doors.

I used to have a Craftsman full sized tablesaw, with cast iron extensions.  It was rather inaccurate compared to this portable Ridgid model.  Very impressed with this!  In a matter of seconds, it folds up upon a built-in handcart.  All the doors were made from a piece of 3/4" oak plywood.

I was careful to keep the wood in the same orientation to maintain the grain pattern.  There are actually 4 pieces of wood here.  This was necessary to accommodate all the piano hinges.  Here seen with a coat of cherry stain.  Later that day all the pieces were flipped over, and the backs were stained.  Tonight I added the first coat of semi-gloss polyurethane.  A light sanding and another coat will follow tomorrow.  The first coat of poly is looking nice!

The first coat of polyurethane on the inside of the doors has dried overnight.  A light sanding to smooth out the rough texture caused by the poly soaking into the wood, followed by a wipe down of a tack cloth to remove the dust, and finally a second coat.

Just have to be careful not to remove any wood or stain.  Only need to smooth out the surface.

All the dust removed with the tack cloth.  Another layer of poly being applied with a disposable foam brush.  Don't push the brush down with any force or it'll create a bunch of bubbles that'll have to be sanded out again.

Two of the three doors done.  Notice how the red of the cherry stain changes colors once the poly is applied.

The back of the doors are done.  I'll let them dry overnight, then decide if they need a third coat.  Otherwise, I'll work on the front side of the cabinet doors.

Update 3/28/12:  The cabinet door front side were sanded after work this evening, and a second coat of poly was applied.  Depending on how smooth the result is, I might sand it again and apply a 3rd coat.  Considering it's going to be a mounting platform for inverters & solar related hardware, probably overkill already.  Not bad for a piece of oak plywood from Home Depot, eh?

81 degrees in the garage this evening.  Ideal time of year for such a project.  Not too hot, and the humidity level is still fairly low.  Also limited number of bugs to get in the freshly applied finish.

Update 3/29/12:  The three hinges were cut to length, removing about 4".  An 18V Dewalt grinder with a cut-off wheel made short work of this task.

A hand file was used to remove the burr left by the grinder.

Nothing fancy.  Picked these up at the local hardware store.

A sharp punch was used to mark the first hole.  A cordless screwdriver was used to put in every other screw.  The doors will be removed to mount the cabinet box to the wall, then the doors will be re-installed with all the screws.  Too heavy to lift it fully assembled.

All hinges installed, only one visible.  Spacing between the doors worked out perfectly.

These are the handles I'm considering using.

The doors operate smoothly.

I'll install a couple of latches that'll hold them shut.

Update 3/30/12:  I spaced the door handles about an inch up, and an inch in from the edge.  Rather than measure, I used a yard stick and a bubble level about the right width, and put them along the two edges of the door.  Lazy, but effective.

All the handles installed.  Time for a little libation to celebrate now the work is done for the evening.

Update 4/1/12:  Nah, no April Fools!  I positioned the two main inverters on the right side door.  To square them up, I used a T-Square along the side of the door.  Each mounting hole was marked with a Sharpe marker, then pre-drilled.

Hardware rusts pretty quick in salty Florida.  I typically used stainless steel hardware.  Not that much more expensive, and will remain corrosion free.  I buy various sizes by the box at my local Ace Hardware store.  Not the cheapest place, but convenient.

The 6" Phillips screwdriver bit in the cordless screwdriver allows the screws to be driven straight into the pre-drilled holes, without the body of the screwdriver hitting the side of the inverters.

Both of them are now mounted to the door.  Next step will be to drill holes for the DC wires on the back of the inverters, and holes for the AC wires on the front of the inverters.

Update 4/02/12:  I made a panel for the two inverter remote displays.  They are mounted in a 4"x6" aluminum plate.  I set it on the door about where it will be installed.  This leaves room underneath for more goodies.

Though the flash picture doesn't do it justice, the hammered black finish, with the black displays, actually looks good.  Without the flash, everything looks pretty much the same shade of black.

Update 4/08/12:  Yesterday the doors were removed and the cabinet base was sealed with polyurethane.  Next step is to cut a piece of 1"x6" pine to make a French cleat, and mount 1/2 on the wall, the other half on the back of the cabinet.  Once the cabinet base is mounted on the wall, the doors will be reinstalled.

Update 4/14/12:  A French Cleat was installed on the back of the cabinet along the top edge.  The screws we slightly countersunk so the screw heads wouldn't get in the way.

The matching half of the cleat gets mounted on the wall.  To hang the cabinet, simply lift the cabinet onto the other cleat.

I used a Ryobi laser level to put vertical lines on the wall.  I first marked the middle of the bench so the cabinet would be in perfectly alignment once installed.  I also marked the wall studs so the upper cleat and lower brace could be attached to the wall.

Drywall screws are prone to sheering.  I don't use them for anything structural.  These are deck screws.  There's a total of 10 of these holding the cleat and bracket to the wall.

This was a bear to lift into position.  That's a 3/4" plywood base with a 1x4" sides, top, and stringers.

The doors will be permanently mounted once all the hardware is installed.  Two Xantrex inverters on the top, a 30A automatic transfer switch on the lower right, and getting ready to cut a hole to mount the remote panels for the inverters.

I use a CAD program to make a template.

Made sure the paper template fit the two displays, with enough clearance for the mounting screws.

I find it easier to mark tape, then cut the tape with a jigsaw.  If I used the paper template as cut guide directly, it tends to tear apart during the sawing process.

Made a pilot hole with a 3/8" bit, then got busy cutting out the material.

A square was used to get the panel level.  A handful of screws, and this task is complete.

The inverters will use 4/0 flexible welding cable.

To keep the wiring inside of the cabinet, I needed to make holes through the doors.  A smaller bit was used to make pilot holes.

I used a hole saw to drill partially through the back of the door so it wouldn't blow out - splinter the wood as the bit came through the other side.

The first hole finished.  This is the back of the door, clean exit wound.

My hole saw kit has a lot of miles on it, not as sharp as it once was, but still gets the job done with some smoke.  I liked that it charred the inside of the hole.  Saves me from having to stain it.

The cable fits through easily.  The connectors should fit through also, which is why the holes were oversized.

The heavy inverters were removed, the door installed on the cabinet, then everything was re-installed for the last time.

The piano hinge easily handles the weight, and the door opens smoothly.  I haven't added a latch yet to keep the door closed.

In this picture you can see the holes behind both inverters that line up with the DC power connections.  Busy day, got a lot done!

Update 4/17/12:  Dreaded Tax Day.  Glad that's over with!  Okay, back to the project.  I decided I would mount the DC power switches low, so that they could be easily reached.  Another one will be mounted in the middle door, which will turn off all the DC loads.  These two will control each of the two inverters.

Started by using blue masking tape so I could put some reference lines on it.  Also reduces potential damage when drilling.

CAD program came in handy again.  Made a template for the Blue Sea P/N 6006 power switches.  I spaced them 4" apart, and centered them with the panel below.

An automatic center punch marked the centers, then a pilot hole was drilled.

I bought a new Milwaukee hole saw just the right size for this job.  Unlike my older bits, this one is SHARP, and kept trying to grab.  I scored the front and back of the door to minimize blow out.

Holes done.  The bit did jump out of the hole a couple of times, leaving tracks on the wood and black faceplate.  Fortunately, I have more stain, polyurethane, and black paint.

Even though I was drilling slow, with light pressure, the bit would catch.  Turns out the plywood layers would crack/crumble, and bind the bit.  I never have this issue when using a drill press.  But I had to drill these by hand, and must have cocked the drill some in the process.

On the next one, I score the fronts of the doors, and do all the drilling on the backs of the doors.  If I mess up, it'll be hidden inside.

Switches installed.  Looks like they were intended to mount in 3/4" material.  They also come with a housing that allows them to be surface mounted.

Turned out well.  I like the placement.  A label under each switch, and a dab of paint, good as new.


Some might say it lacks Feng shui, whatever that is.

Update 4/19/12:  Time to install the bus bars.  Needed to make an access hole in the bottom of the cabinet.  Most of it was cut with a jigsaw.  A Harbor Freight Multi-Function tool was used to remove the rest.

Now there's room for the battery cables.

The bus bars had been previously built for my original setup.  It worked out well enough to use it again.  Details about that build here: Link  A Lexan cover mounts over the bars to prevent any accidental shorting.

Overall view.  Now I can begin mounting hardware on the middle door.  There will be a switch to turn on/off all DC loads, an Iota 24 position fuse panel, and a 75A Iota battery charger.

Update 4/20/12:  Work on the middle door begins.  The Iota 75A charger was centered, and mounted to the surface of the door.  Holes will be drilled above the charger for the AC power cord, and the two DC power cables.  Haven't decided where to mount the IQ4 module yet (little black box on the right).

The advantage to staying with a 12V setup is the amount of available hardware.  I cut a hole for an Iota 24 position fuse panel.  This will be used for all the low current DC loads.

A quick test fit to make sure it fits and is level.

Fits fine.  A stainless steel screw in each corner, done.

Here's how it's shaping up so far.  I have to be careful not to mount hardware that protrudes through the door below the upper piece of blue tape.  Below the line on the tape will be the bus bars inside the cabinet.  Wouldn't want components on the front of the door to end up interfering with the bus bars inside the cabinet.

I'll probably mount the power switch for the DC loads, and the LinkPRO monitor, just below the fuse panel.  I'll sleep on that one, see how I feel about it tomorrow.  The third door will hold the multiple solar charge controllers, voltmeters, switches for DC loads, etc.

Update 4/21/12:  Decided to go with the layout previously mentioned.  Two pilot holes, then drilled two different sized holes for the battery switch and the LinkPRO monitor.

Same as before, drilled part way through the front, finished by drilling from the back.  I loosened up the clutch on the drill, made handling the aggressive drill bit much more manageable.

A square and a spring clamp held the switch level while I drilled pilot holes for the 4 screws.

To make the smaller holes for the cables going to/from the Iota charger, I used a set of Forstner bits.

Unfortunately, there was a bit of tear out between the two smaller holes.  No biggie.  I could put a piece of trim on it, but a tad of stain, it'll disappear when the cables are fed through the holes.

Middle door then mounted to the cabinet.

If I had mounted the switch and LinkPRO monitor lower, they would have interfered with the bus bars when the door is closed.


Next step will be to work on the third and final door.  Once the charge controllers, meters, and switch panel are installed, the door will be installed.  Then the wiring can begin.

Update 4/22/12:  We spent a good part of the day entertaining family today.  We had a pool party at our house.  Lots of food, fun, and screaming kids.  I needed a short nap after all that!  After I recovered, work started on the third door.  Three charge controllers were mounted, along with a switch panel.

Not planning on adding anything else to this door at this point.  Leaves room for system expansion later.  The bugs moved into the garage when the sun set, so I called it a night.  Tomorrow the door will be mounted.

Update 4/23/12:  I have other projects planned tonight, so couldn't spend much time on this one.  I did take a few minutes to mount the 3rd door onto the cabinet.

The battery bank sits just below the cabinet on a 36" tall heavy duty workbench.  The bank consists of eight 6V golf cart batteries, paired up to make 12V, and 4 groups in parallel via the bus bars.  Provides about 900 AH at 12V.

Update 4/29/12:  The cable used for the inverters, and the shunt, is 4/0 cable.  Massive stuff.  The best way I've found to cut this is with my bench top bandsaw.  I use a push stick, and feed it slowly.  It's important the conductor be cut cleanly, or it will not fit in the connector without strands of copper sneaking out.

I've been using an anvil type crimper for a while.  This one will easily handle 6 gauge to 4/0 cable.

Once the connector is slipped onto the cable, they are put into the anvil crimper, and bashed repeatedly with a 5 lb mallet. 

After 5 or 6 good whacks, the anvil makes a solid sound when hit.  This is the back of the connector.  A good - deep indentation.

The top side of the connector has shiny bands from crimping, without distortion.  Ready for installation.

My goal today was to get the shunt installed with a power cable from the negative side of the bus bars, and to wire up the Iota 75A charger with a circuit breaker inline.  The yellow wires are AC  power and will be permanently routed once the inverters are wired.

It was a hot day in the garage, but now the battery bank is being charged/maintained via the Iota 75A charger.

Update 5/6/12:  Spent much of the weekend doing PM on my truck and camper.  Only spent a brief time working on the panel.  I did manage to get power to the Iota 24 position fuse block (black box at the top of the pic), via the Blue Sea power switch, and a breaker.  The Xantrex LinkPRO is getting power from the first fuse position (far right).  The grey data cable goes up to the shunt, and connects to both sides of it, and to ground.

Having wired this before, I cheated.  I used the same cable as before.  I cut the wires a couple of inches from the LinkPRO and shunt during the move.  Made figuring out which wire went where very easy since they are all color coded.  As mention before, the yellow AC power cables are temporary.

The overall view.

The LinkPRO battery monitor is working once again.  The battery bank is being kept fully charged via the Iota 75A charger for now.  Next month the solar panels will be installed if all goes as planned.

Update 5/7/12:  In order to get wires in/out of the cabinet, the easiest path is via the attic.  A piece of electrical conduit will be placed in each of the 3 cabinet bays.  Before making a large enough hole for the conduit, a 1/4" pilot hole is drilled through the cabinet, and through the drywall ceiling.  If I don't like the location at this point, only a small hole to patch.  Be careful to only drill through the cabinet and drywall... not all the way through the roof!

The Greenlee Fishstik kit I have contains 24' of flexible rods.  All but one of the sections is green.  The white one glows in the dark, making it a bit easier to spot in a dark attic.  It was pushed up through the hole until it wouldn't go any further.

Time for a hike into the attic to find the Fishstik.


On the left side of the foam baffle, the tip of the Fishstik can just be seen.  Rather than climbing through the insulation, and over the power cables, I will take the time to deck this section of the attic.  While it will take more effort initially, it'll sure make routing cables through the conduit far easier in the future.

Update 5/8/12:  While working above the bus bars, I got concerned about dropping a wrench onto them.  I did make the center divider longer than the bars, hopefully preventing something from being able to touch the positive and negative bars at the same time, but that's a LOT of potential energy if something did.  I took a couple of scrap pieces of Lexan, and bonded them together with a little IPS Weld-On 3 adhesive.  You can find this at places like Tap Plastics online.  Be sure to watch their YouTube videos for instructions.

Two screws and the Lexan L-bracket is secured to the back of the cabinet.  The front cover can still be removed without having to remove the top cover.  Simple mod, but might make the difference between simply picking up a dropped tool, or watching a fireworks display!

Update 5/9/12:  I took a few minutes to install a magnetic latch on each of the three doors.  Since the doors are slightly longer than the base cabinet, I opted to put the latch under the cabinet.

These were $1.39 at Ace Hardware.  Nothing fancy.  Metal plate mounts to the door, magnet to the cabinet.  When the two meet, the door stays shut.

Okay, onto the power cables for the inverters.  I'm using 4/0 cable.  The lugs have a hole much larger than the power posts on the inverters.

To get a good compression of the lug against the conductive surface, I used a fender washer, followed by a lock washer, and finally the nut.

The hole on the fender washers was slightly undersized.  Wouldn't fit over the power post.

A Unibit made short work of opening up the hole.  I put these sort of details to show how many little frustrating issues are quickly resolved.  No project ever goes without problems.

Once the cable was connected to the inverter, it was routed to the shunt, marked for length, completely removed, cut, then a lug was put on the far end.  Then the entire thing was installed again.

A 1" spade bit was used to bore a hole between the cabinet walls.  The hole not only has to be large enough for the cable, but also the connector.  I didn't measure the lug before drilling the hole, and I got lucky, it just fit.

Update 5/10/12:  I went ahead and ran the ground wire to the second inverter, then started wiring the positive wires.

I quickly ran out of terminals.  We were going out to dinner tonight, and Ace Hardware was 2 minutes from our destination.  Got there just before they closed, and bought all they had.  $6.99 per pack.  Far cheaper to buy them in bulk online.

Each inverter will get its own 250A fuse.  This is a Class-T type, and is sized per the manufacturer of the inverters (Xantrex).  These are expensive, and hard to find locally.  I keep a spare on hand, plus only one inverter will likely ever be used at a time. 

I ran out of juice at this point.  Now need to connect both fuses to the positive bus bar, and the upper inverter to the switch.  But I only have enough cable to wire one fuse.  I'll have to measure/order more tomorrow.  I WILL have one inverter up and running by this weekend.  Hurricane season is three weeks away.

Update 5/13/12:  I had enough 4/0 cable left to wire one inverter.  A cable was cut to length, connectors added, and attached to the upper fuse block.  I also need to order some 1" diameter black and red heat shrink tubing.

I verified the switch going to the inverter was off, then attached the power cable to the positive bus bar with 1/4" stainless hardware.

I haven't installed cable clamps yet, this was more about making it functional tonight.

The master power switch to the inverter was turned on, then the remote power switch was pressed.  Green light, and the inverter comes to life!

A 1500 Watt heat gun was connected to the inverter.

The heat gun was powered up for several minutes, giving the inverter a good workout.

The display is hard to read in this picture, but it says 1.56 (KW).

Even with the Iota 75A charger trying to keep up with the load created by the heat gun, the LinkPRO shows an additional 78.3A is being taken from the battery bank.

Update 5/14/12:  Worked all day, came home and cut/edged/trimmed the lawn, then got a little time on finishing the panel.  I started by cutting a 2" hole in the top of the cabinet and up through the drywall of the attic.  I had previously drilled a pilot hole, and verified the location in the attic.

To secure the conduit in place, I used hot glue.  It'll stay in place unless I ever decide to remove it.  It's only 40W, but I used the inverter anyway.

Before putting the conduit in place, I pulled as much insulation from the hole as possible.  My goal is to fish wire UP into the attic, then use a Greenlee Fishstik to grab it and pull it to a taller part of the attic.  By doing this, I don't have to crawl to the skinny part of the attic.  Uh, no, I didn't take a shower after cutting grass, and starting this one.  Saved that for later.

I cut each piece of 1 1/2" (Inside Diameter) about 8" long on a bench top bandsaw.

Knowing that there isn't much attic space directly above this, the conduit only goes into the attic about an inch.  A layer of hot glue was put everywhere I could reach.

Doesn't take long to setup.  Does a good job of holding the pipe in place.

With the cabinet door shut, this is all that can be seen for now.  Eventually, a piece of trim will go around the top of the cabinet, hiding the conduit pipes.


Update 5/15/12:  Got some lawn work done after work today, had dinner, then decided to try pulling a cable with the Greenlee Fishstik, rather than climbing across the rafters and insulation.  I took a 10 gauge wire, doubled over the end, wrapped it with electrical tape to create a loop, and shoved it up through the conduit into the attic.  I couldn't see it from above.  Still buried in the insulation, note the pink wad on the end of the stick.  The hook in the Fishstik found the cable, and yanked it over to me.

Happiness is not having itchy skin from exposure to insulation.

The cabinet end of the cable.  It will be clamped, labeled and terminated.

Next, more conduit will be installed between the top of the cabinet, and the attic.  One will hold wires from the solar panels, another the wiring for DC loads, the final one will hold all the AC wiring.  
  Keep checking back, updates should be every day or two for a while.

More photos to follow soon.

Please keep in mind nothing I'm doing here is very complicated.  I'm showing more detail that many would care about, but some might find it useful.  Most of my progress is made after work, spending maybe 1/2 hour to an hour at a time.  Usually in the evening, after dinner, and some lawn work or house chores.  Good way to wind down.




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Last updated 5/15/12    All rights reserved.