Disclaimer!! I have never claimed to be an expert so this is not a how-to but rather a how-I-did-it.
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| Looking down into the electrical compartment under the gaucho. The cushion and house batteries have been removed for now. |
OK, so yeah, this is probably not the kind of
re-power all you gear-heads were thinking about, but The Van, and I, feel a lot
better now that I’ve pulled the $650 Tripp-Lite Inverter/Charger, that silver
ribbed box in the lower left, with its 2000 Watts of inverter power and 50 amps
of charge current
and replaced it with this $150, 15
amp IOTA Converter with IQ4 charge
controller.
Some of y'all are going to shake your heads and wonder just what this fool is thinking, going backwards like that! And that's understandable.
But think of it in terms of a
couple owning a 5-bedroom/5 ½ bath house that they only use a fraction of; oh,
and by the way, the furnace needs replacing. Now think of them selling that house and
replacing it with a 1 bedroom/1 bath + den bungalow that they use every room
of. Setting aside all that ‘Great American
Dream’ crap that Madison Avenue has indoctrinated us with since birth, is that really
going backwards, or is it intelligent asset and resource management??
OK, regardless of what you think about
that scenario, before I get to the nuts and bolts of actually making the equipment
switch let me run down my reasoning here. It might not change your opinion of how many marbles my jar still holds, but then again, who knows. . .
True, by giving up the Tripp-Lite
inverter I no longer have access to 120V power when not hooked up to
shore-power; but then again I hardly ever used the inverter anyway. In fact the
inverter had far more time on it from the 15 minute monthly test/exercise it
got than it ever had for real. Oh, and by the way, (See how I cleverly repeated
that phrase from a couple paragra - - Oh never mind. . .) during one of those
monthly tests I discovered that the inverter had failed. (Which is exactly why
I’m a stickler about regular tests of things not often used. Find out before
you need it!) This failure was disappointing given how few hours the inverter
had been run in its 4 years of active life (Yep, a year out of warranty!) but
since I didn’t use it anyway, no big deal; except that I began to suspect that
the dead inverter was bleeding off a few of my incoming shore-power volts. (I won’t
get into the guts of how inverters like this work other than to point out that
shore-power has to be processed by the inverter before it’s passed on to the
rest of the electrical system and I’m not sure all of it was being passed on.)
True, by replacing a 50 amp charger
(The charger portion of the Tripp-Lite continued to work after the inverter
failed.) with a puny 15 amp charger it’s going to take a bit longer to recover
from a deep, or even moderate, discharge state; but, with 180 watts of solar on
the roof and modest usage I don’t get into a deep-discharge situation very
often, and even so, whenever I plug into shore-power it’s going to be at least
12 hours before I unplug again, so what’s the rush? In fact, fast charges put
more wear and tear on batteries than modest charges, yet even with the
Tripp-Lite set to low-charge-current mode in an attempt to mitigate this
fast-charge stress, it still output nearly 30 amps.
True, even throttled back to low-charge mode the
Tripp-Lite could easily support almost 30 amps of prolonged 12V load; but my
peak 12V load is more like 10 amps, and then only when I’m trying to get it up
there by running the fridge, the fantastic vent fan on high, the overhead
recessed lights (So bright I call them landing lights) charging up my laptop
and plugging in the 100W inverter to charge some dead double-A’s, all at the
same time. The 15 amp IOTA can handle the 10 amp load just fine.
As you can see in the photo above,
which I didn’t think to take until after I ripped the face off the Tripp-Lite,
and I’ll get to why in a moment, there is a big size difference between the
Tripp-Lite and the comparatively puny IOTA. Since, for obvious reasons, I will
not be using the recovered space there in what amounts to an electrical
compartment for extra storage, the size difference is not a big gain for me, but
the Tripp-Lite has one big-ass transformer and equally big bits and pieces
which makes it tip the scales at over 40 pounds. The IOTA doesn’t quite get the
needle up to 5 pound mark, saving me 35 pounds! Since, collectively,
the cabinet doors weigh in at a hair over 35 pounds it’s like I’m carrying them around for
free now! (And I get one heck of a lot more use out of the cabinet doors than I did the Tripp-Lite.)
The IOTA is actually a converter,
designed to take 120V AC power and deliver 12V DC power, with this model up to 15
amps of it. Hand in hand with the IOTA is the IQ4 Smart Charging module.
Without this module the IOTA outputs a steady 13.6 volts which is great for a
converter but sucks as a battery charger. With the IQ4 module added the IOTA is
turned into a proper 3 stage battery charger (The 4th stage of IQ4
is sort of a mini-equalize which pulses on for a short period after a prolonged
float mode.)
I nearly screwed up when ordering my
IOTA. I knew I wanted the IQ4 module but without paying enough attention to the
details when I was surf-shopping for the best combination of price and shipping
costs of the moment, I actually had an IOTA without IQ4 in my cart at one
point. . . Not a fatal mistake since IOTA offers an external IQ4 module to
upgrade your unit, but still. . .
Now on to the actual
demolition/installation.
The first step, in order to prevent
any electrical accidents detrimental to my health, was to disconnect
shore-power, the solar panel, (
This explains why that is so easy to do on The Van) and the batteries. In this case, since I will be replacing the
batteries anyway I just went ahead and removed them altogether. (No need to
worry about dropping a tool across the terminals when there’s no terminals
there to drop a tool across!)
The IOTA is pretty dang simple.
Connect positive and negative wires out to the batteries, ground the IOTA box
to The Van’s chassis, and plug the thing in. Done.
Ripping the Tripp-Lite out – well,
that complicated things a little.
If I just disconnect the wires, in
itself not terribly easy when it means horsing a 40 pound chunk of steel around
in a tight space to get at the various connections, then I’ll never get
shore-power into The Van’s distribution center because I have one wire coming
from the shore-power plug, the upper Black/White/Green set, and a separate wire
that goes on to the distribution panel, the lower Green/Black/White set.
Without the Tripp-Lite in between I
need to splice those two sets of wires together because the alternative is getting
at the backside of the shore-power connection itself to re-do the wiring and
eliminate that first wire altogether, but that means pulling out a wall, which
means pulling out the gaucho and fridge cabinet, which means pulling the
overhead cabinet too. Yeah, not going to happen!
The simplest way to make the splice would
be to install an electrical junction box with proper cable clamps attached, all necessary
to satisfy code requirements, (And you do not want to screw around with
electrical stuff and cheat on code because it will either burn your place down
or kill you; sometimes both!) then splice the wires together inside the
enclosure with red wire-nuts.
But these wires are stranded. Solid
wire is what you usually find inside the walls of homes and it goes under outlet screws and into wire-nuts very well, but stranded wire
bends much easier around tight curves which is a decided advantage when running wire in a small,
tight space like The Van.
Technically I can use the wire-nuts to join stranded wire, but in my experience I
not only need expensive nuts, (Not all wire-nuts are made equal so beware!) but
I also have to make the join perfectly, and even then, even with the nuts taped
over and back onto the wire itself in a clockwise direction (When looking down
at the narrow end of the nut.) with slightly stretched electrical tape to
reduce the chance of vibration and/or the natural heating-cooling cycle from
loosening the nut, I’ve still come back later and found stranded wire-nut joins
loose enough that I could pull one of the wires right out of the splice by hand.
So I’m standing there wondering what
to do next when my eye falls on the splice-block there in the Tripp-Lite, that
white, vaguely ladder-looking thing and I think ‘perfect’, This type of
splice-block will grip stranded wire without loosening up over time and has
plenty of contact area to pass 30 amps
of power without heating up. (Heat represents lost voltage.)
Only thing is, I find out I have to
get to the back side of the Tripp-Lite front panel to remove the bolts holding
the splice-block in place. That took a while but I was not going to be deterred by a big chunk of inoperative metal!
By the time I finally had the block in
hand the Tripp-Lite was a little worse for wear. . .
It took a lot less time to grab an
electrical enclosure and a couple cable-clamps from my junk box, cut
the splice-block down to the three positions I need, mount it inside the box and
splice the two cables together.
As per electrical code, this splice
is not only protected inside a securely mounted enclosure, but there is access
to the enclosure for future inspection/service of the splice. (I have a
reminder in The Van’s log-book to check the splice after a couple hundred miles
of driving just to make sure.) By the way, though it’s commonly done, hiding
wire junctions like this behind drywall, siding, or anything else that impedes access to it is a BIG no-no and if
you ever catch your electrician/contractor/builder doing that: 1) wonder what
else he/she has cheated and skimped on:
2) fire him/her on the spot and find someone else that will do the job
right.
Although code requires it anyway,
because this junction box is electrically isolated, sitting there on the wood
floor like that with no other electrical path to ground, it’s especially
important to make sure that short little ground jumper is in place. That
ensures that if the incoming black wire, the hot wire, does ever get loose and
touch the box itself the 30 amp breaker will trip before I can reach down there
and grab a live box!! Likewise, the presence of this little jumper means if the
white wire, the neutral, gets loose it will trip the GFCI.
At this point I closed up the
enclosure, plugged back into shore-power and verified that all my 120V stuff
was working.
The next challenge in installing the
IOTA is, once again, the fault of the Tripp-Lite.
Because the Tripp-Lite can
output 50 amps of 12V the leads connecting it to the batteries are hefty to say
the least! Even if I cut the crimped-on eyelets off these cables there is still
far too much wire to fit into the terminals on the IOTA.
My solution, which I didn’t think to
photograph until after the fact, was to crimp some large eyelets onto lengths
of appropriately colored #10 wire and bolt the eyelets together, red to red and
black to black, creating short pigtails that then fit into the IOTA’s
terminals.
I wrapped the exposed eyelet – bolt combination
with two layers of 600 volt electrician’s tape and one layer of black
duct-tape. First a layer of electrical tape to insulate the area, then a layer
of duct-tape to provide mechanical protection (Duct-tape stands up to abrasion and
blows (From dropped tools, etc.) better than electrical tape.) then a final
layer of electrical tape to add even more insulation but more importantly to
catch and contain any loose edges and streamline the joint so nothing snags on
it.
It looks really strange to have a
small wire like that going into such a fat wire, but electrically it works. The
IOTA will output 15 amps max yet the 4 inches of #10 wire, the small stuff,
will safely carry up to three times that for a prolonged period. (The longer
the length the less current a given wire size can carry, conversely, the
shorter it is the more current it can safely handle.) The 36 inch long fat
wires were sized properly for the Tripp-Lite which means they are much bigger
than needed for the 15 amps from the IOTA, but electrical current only cares
about too little wire, never too much, so they will do the job just fine and this
way I didn’t have to tear into mostly hidden wiring harnesses to replace them.
There are two other things of note
in the photo above.
One is the white chassis ground wire
that is run back and connected directly to the metal of The Van itself. Again
if anything ever goes wrong this wire provides a clear and concise path to
ground which will trip any protective breakers or blow any fuses before I can
kill myself by grabbing something live.
The second thing is that both the black
and red feeds have been secured in place with cable-clamps, most easily seen on
the red wire as a black band at the left edge of the photo. This keeps them from moving and chaffing while
The Van is moving and chaffing. It also means that if I inadvertently snag one
of these wires while messing around inside the compartment, the clamp will help
prevent me jerking anything out of its terminal, and since that red wire is connected
directly to the hot side of 200 amp-hours of battery, if it got loose that
could be a problem! Those cable-clamps are a few pennies each and take about 5
seconds to install so there’s no excuse!
The final step in installing the
IOTA is to plug it in.
Once plugged in it’s on and the only
way to turn it off is to unplug it. Since I only have shore-power available for significantly less than 50% of the time I’m camping, and I actually use the charger even less
than that, leaving it turned off most of the time and relying on the solar system to keep things topped up, I wanted an easy way to
start and stop the IOTA and I wanted to do that without cutting the power cord
since that voids the warranty.
I could have added a switched outlet
facing the inside of the compartment and left the IOTA plugged into it, turning
it on and off with the switch, but it just seemed simpler to utilize the outlet
already mounted right there and simply plug the IOTA in when I want it running and
unplug it when I don’t.
So I drilled a hole through the face of the
gaucho sized to be a friction fit for the back-side of the IOTA’s plug, then cut a slot into that hole from the nearby vent opening (This vents
the electrical compartment and based on previous experience I went with an oversize vent for the area when building The Van.)
Now all I had to do was use the slot
to slip the IOTA’s power cord into the hole then mount the vent cover to trap
it there, and cover up the unsightly slot.
Now when I want the IOTA running all
I have to do is pull the cord out a little and plug it in, then reverse the
procedure to turn it back off. All without having to raise the heavy gaucho cushion
with one hand while fishing around inside a dark compartment filled with electrical stuff with the other like I had to do
to turn the Tripp-Lite on and off.
It might look like this is all
sticking out too far and likely to get snagged when I’m moving around in The
Van, but what you don’t see here is the gaucho cushion, which I removed to
make access to the electrical compartment easier. When reinstalled it will
extend over the face of the gaucho by a good 4 inches and the outlet and power
cord will be tucked neatly underneath it.
The moment of truth was to plug the
IOTA in and close the 12V disconnect switch, that black rectangularish thing
under the outlet. All my 12 volt stuff came back to life and the voltage was a
steady 13.6 volts since the IOTA was operating in converter mode because there
were no house batteries installed at the moment.
More about the battery issue later
but for now it’s time to put the tools away and clean up the mess.
