Modifications and Panel Completion

Chilly weather this past weekend made good project weather.  I had two primary projects that I have been looking forward to completing, the dash panel and modifications to the 48 volt charging system.

Charging Modifications

When I first installed the 48 volt charging system, I made use of a 12vDC -120vAC inverter that I have had on a shelf in my shop.  This inverter served us very well for years, installed on our boat but in the WattCycle I was getting poor results.  I would find that the 48 volt charging system would only trickle charge the batteries when plugged into the inverter but operated fine when plugged into utility power.  The reason, the sine wave output that was produced by the inverter.

Inverters - Modified Sine Wave or Pure Sine Wave
An electrical sine wave is the repetitive oscillation of voltage from negative to positive and from positive to negative.  This sine wave or oscillation makes our common AC electrical work.  An inverter can either make a pure or modified sine wave depending on the technology incorporated.

Modified sine wave
The output of a modified sine wave inverter is similar to a square wave output except that the output goes to zero volts for a time before switching positive or negative. It is simple, low cost and is compatible with most electronic devices, except for sensitive or specialized equipment.  Most AC motors will run off this power source albeit at a reduction in efficiency of approximately 20%.

Pure sine wave
A pure sine wave inverter produces a nearly perfect sine wave output (less than 3% total harmonic distortion) that is essentially the same as utility-supplied grid power. Thus it is compatible with all AC electronic devices. Its design is more complex, and costs more per unit of power.

The inverter I first installed was a modified sine wave inverter that powered up a coffee maker, charged cell phones and even operated a microwave but it was clueless when it comes to a 48 volt smart charger.  I upgraded to a pure sine wave inverter and now my 48 volt battery pack gets full power whenever I need it. 

Dash Completion

Cutting, drilling, fairing and sanding followed by priming, sanding and painting.  The dash needed completion to finish off my project and also protect everything that I have assembled.  Now that all the dash parts are put into place and the finish is applied, the project is taking on a completed look.  I wired the last switching circuit for the next project, lighting.  I now realize that I forgot one valuable option...cup holders!

Dashboard

Watts Up had another very successful, emissions free, electric day.  I had the chance to ride farther and harder than I have done in the past, pushing the batteries and charging system to the limit.  Trips to marinas, vendors and even a trip to the bank and grocery store before my day was done still left me with enough power to get back home.  Never was I without power even when I put another 60 lbs of groceries in the cargo box.  After leaving the grocery store, I had to motor into a 15 mph wind with additional weight of goods.  I noted that my power consumption was 20 - 25 amps while loaded down and heading into a stiff wind.

While waiting for a left turn signal at an intersection, a trucker asked me "You got a motor in that thing?".   When I replied yes, his response was, "Thought so, you was going too damn fast!".

The New Dash
My mission tonight, once my day was done, was to make a dashboard for all the metering devices and power switches that the cargo bike needed.  The project started as just a prototype but turned into the actual dash once I saw how easily it was coming together.  With some scrap 1/2" birch plywood that I had in the shop, I was able to come up with a basic dash that would accept all the gauges and switches that I had anticipated.  The dash would be installed just forward of the handlebars and just behind the solar panel located on the cargo lid.

I have installed a main power switch on the far left, the Ganz solar charge controls, power meter and a light switch on the far right.

Watt's Up Meter
I was needing to monitor voltage and amperage consumption on the 48 volt propulsion system, something that would act as a fuel gauge and tachometer that you would find on a typical automobile.  I was searching online for digital or analog gauges when I stumbled across the Watt's Up Meter.

OK, what are the chances that Watts Up Marine would find a voltage/amperage meter that is called the Watt's Up Meter?  How could I say no to such a purchase?  It turned out to be a very successful find. 

This device was designed for radio controlled electric cars, planes and boats but has some very high voltage and amperage spec's.  I was nervous at first, worrying about the amperage demand that I needed to run the power hub.  The Watt's Up Meter is rated for up to 60 volts and can handle up to 100 amps of current draw.  The WattCycle is rated for a maximum of  30 amps at 48 volts, the new meter should be more than I need.  The display reads amperage draw, battery voltage, amp hours consumed,  peak amps, watts and watt hours.

The only complaints that I have with the Watt's Up Meter is the size of wire and length of wire that they supply.  I have wired the WattCycle with 10 AWG wire to handle the 30-40 peak amps that the hub will be drawing, however the Watt's Up Meter comes standard with 14 AWG.  To me this looks like a weak link in my chain.  The length of the standard source/load wires are only about 6" long, you do not get many chances to make waterproof connections without running out of wire leads.

I now have the beginnings of a dash panel.  I intend to complete the box, fiberglass it and give it a complete coat of Awlgrip just like the cargo lid that it will attach to.  I would like to have a completely sealed unit by the end of the week.  It is all coming together.

Full Day at Work

Today was Watts Up Marines first full day of using the WattCycle as our primary service vehicle, it was flawless.  I am proud to say, not an ounce of fossil fuel was consumed to get me from my home, shop, vendors and clients.  I could have put the bike into operation last week however mother nature did not give much of a weather window, it rained heavy or was threatening many of the days.

Kemah, TX

Kemah is a great city to live in, it is a small coastal community with great eats, entertainment and convenient shopping.  As a sailor, it gives me the ability to live within a couple miles of my boat, minutes from great sailing and access to the Gulf of Mexico.  One shortcoming however, is that they do not offer a friendly environment for bicycle traffic. 

There are no bike paths down the major thoroughfares, the roads were built without bike lanes and many of the streets are narrow.  If a sidewalk does exist, it is about two feet wide, weaves under overgrown vegetation and likely comes to an abrupt end in a block or two.

While out riding the cargo bike, I often encounter some rather aggressive motorists that have love affairs with their horns.   On one particular four lane road, they could easily move over to the left lane to go around a bicycle however they find that their horn is somehow a much more satisfying solution to their frustrations. 

...All smiles

What really amazed me today, was my ability to travel down heavy traffic streets and maintain enough speed so I did not annoy most of the gas guzzlers.  I even had the power and speed to dart across busy intersections that normally I would have had to wait for the most opportune moment. 

Today did not offer perfect conditions for a solar charging system, it was an overcast day with small bursts of hazy sunshine. I am happy to say that even with the minimal direct sunlight, the solar panel was filling my charging batteries with enough power to keep my 48 volt propulsion system charged all day. The sunny summer months here in Southern Texas should give me everything that I was hoping for in a zero-emissions vehicle. 

My typical day consists of several short trips to marinas, pick up supplies, meet with customers and runs to the shop, broken up by longer durations camped out, in a sunny marina, working on a yacht.  For the most part, this would be great solar charging conditions. 

As time allows, the next projects are building a dashboard for gauges, meters and a key switch, adding lighting and getting the company graphics applied to the box.  The company logo might have to be first on the priorities, maybe then it will put an end to the request for hot dogs, Popsicles and cerveza...no, I doubt it.

Today was a great start!  It proved that I can operate my business without the need of fossil fuels for transportation.  There will come days that will require me to pull out the gas burner but this is one step closer to freedom!

Speed Test

Today I had the chance to take the WattCycle out on the road and see what she would do.  I had to make a quick run down to the local Radio Shack to pick up the needed parts to repair the inoperative 110v inverter, just the excuse needed to take it for a quick spin.  For my first test, I loaded most of my important tools and test equipment, these add about 200 lbs to the cargo box.  I have found that the bike feels more stable with the added weight.

While out on the road, I was hoping to get a good video, monitor amperage draw and compare it to speed.  I was unable to get any useful video and monitoring amperage was impossible, I needed both hands on the handlebars, brakes and throttle.  Future additions to the bike will be voltage and amperage monitoring, lighting and a keyed power switch.

I did get a good feel for the speed that can be produced.  When on a straight path, the bike easily accelerated, even with the weight that I had loaded in the cargo box.  Zero to twenty was a breeze and accomplished in a matter of a few seconds, however once the bike got over 15 mph or so it would feel a bit squirrelly.  My top speed according to the GPS was 21.9 mph, a speed I would not be comfortable maintaining unless I installed a larger steering stabilizer under the cargo box.  I was comfortable keeping 12-18 mph and think that most of the time that should be enough speed for my taste.

Inverter Repair and Install

When I returned to the shop, I was able to repair the inverter that did not work for me yesterday.  I was lucky to find a bad resistor and fuse on the internal circuit card, both easily replaced with a soldering iron and some patience.  This repair made my day, I had no desire to purchase another inverter for this project.

Once installed, the inverter now supplies 1000 watts of  power to my 48v charging system from the dual AGM batteries.  I will also use this power, to run power tools in case I am located in a remote location.


A battery selector switch allows me to shut down 12 volt power, isolate one AGM battery or combine both for more amp hours.  The solar panel on the cargo lid keeps the AGM batteries charged, hoping that I can store enough energy during the day, to either charge at the job sites or at night in the shop.  This should keep the WattCycle completely off the grid if my plan works.

One slight hiccup today was the flat front tire that greeted me after the initial ride.  It seems that I must have hit something sharp, puncturing a wonderful little hole in the tube.  It was a great opportunity to learn how easy it is to change the tube in the front tires.  Due to the design of the BoxCycle, the front rims are not enclosed by a fork assembly, changing a tire has never been easier.

Now that the tire is changed and electrical system fully functional, it is time to put it to work. 

The Hub is here!

2000 watt rear hub

Today was a monumental day at Watts Up!  It has been a few weeks since we ordered the motor and controller, the anticipation was that of a child waiting to open a beautifully wrapped birthday gift.  The parts were sitting at the doorstep when I returned from work, it took me just a few minutes to rip open the boxes and make my way to the shop to begin the install. 

The new hub and controller are able to function with voltages from 36 to 72 volts DC.  I will be using 48 volts for this upgrade however if I chose, I have the ability to step up to 72 volts to increase power and reduce amperage.  The change to 72v will require two additional lithium batteries, a different charger and reprogramming the motor controller but it will make this bike a freak on wheels.  The hub was designed to deliver 40 mph at 72 volts!  After initial test rides, I can tell that the current configuration will offer more speed than I will comfortably want.

Seven speed freewheel

The stock hub had an internal seven speed shifter and one 19 tooth sprocket, however I had the new power hub shipped with a seven speed freewheel.  I currently intend to find a good sprocket combination and use it as a single speed drive.   When installed, I put the chain on the 3rd sprocket (15 tooth sprocket) just to see how this works, I may move it down to the next smaller size to increase speed while pedaling.  Lucky for me, there are not many hills to climb between my shop and client vessels, one speed should work just fine.  A derailleur system can also be added if I feel the need.

Solar charger, two AGM batteries, 4 lithium batteries,
AGM selector switch 48 v charger and the motor controller

The majority of the electrical had been installed previously, the solar panel, charge controller and the primary/secondary battery banks.  I had one glitch with my initial plan, the 1000 watt inverter that I have had in my shop failed to work when I installed it.  I will have to locate a new one before my "off grid" charging system will work as designed.

The install of the controller (Black box located at the far upper right of the photo) was fairly simple, add power from the batteries, install the throttle control (not shown) on the handle bars and install the power wires to the rear hub.  I used #10 gauge wire to insure that it could handle the amperage needed from the controller to the hub.

Tomorrow I will be doing some speed trials and endurance testing to see how she stacks up.  Stay tuned for data, more photos and some videos of the ride.  Wheee dogggie!

Solar Panel Install

In the past couple days I have received the Sunwize 65 watt solar panel, Ganz solar charger, Ganz remote display panel and the Soneil 48 volt DC charger.  The only items that are left outstanding are the 12 volt AGM batteries, the power hub and the motor controller which shipped today.

Mother nature gave us the gift of large quantities of rain today, making it a great day to work in the shop, installing and testing the new solar system.




Solar Panel Mount

Mounting post located at bottom corner of solar module

My first task was to install the solar panel on the top of the cargo lid.  I used some 1 1/2" #12 machine screws and a nut to create a secure mounting stud and then pushed some rubber pads on to the stud that created an excellent mounting surface.  It is my understanding that heat can limit the solar panels ability to produce power, my intentions were to allow air flow under the panel to let out heat and moisture.  Some 3M 4000 sealant was used on each mounting pad before the final mount was made.

Before permanently mounting the solar panel, I had to make preparations for electrical connections to my solar charge controller.  My expected current from the solar panel is under 4.5 amps however to insure that I had no voltage loss, I used some #10 tinned, marine grade wire to connect between the solar module and the solar charger. 

A water tight seal was needed on the top of the cargo lid so that the electronics and my work gear stays dry.  I used a marine clam connection for the wire penetrations and mounted it deep under the solar panel. 

Solar panel standing upright before install

Electrical seal on cargo lid

Ganz remote charging display

Charge Controller
 After all of my electrical connections were complete, the testing went very well.  The Ganz charger display panel measured the voltage from both battery banks and also the voltage off the solar panel.  Even with the current conditions, cloudy and rain, the solar panel was able to provide 18.7 volts to the charge controller and charge the batteries.

I am very impressed with the Ganz system, it is able to automatically charge two banks of batteries and select the bank that needs it the most.  It will show amp hour charge, amp hour draw and ambient temperature.  The green light at the top of the panel indicates charging condition and an error light is located to the right.  Installation was a breeze and I could use and understand the display panel without the need for instructions. 


Next I will make a dash panel that will contain the solar display, power switch, speedometer, etc.  The rear power hub should have shipped by now and will make an update once I get it installed.  Until then, lets change the world one mind at a time.

Charging System

Now I can get into the charging system, which for me is the fun stuff.  It has always excited me to deal with capturing energy from nature.  Solar power and wind power generation is like magic, the stuff amazes me!  Even though the expense up front is hefty, it always feels good to operate electrical devices without plugging into the grid.

What I am attempting is to be able to charge our propulsion batteries without having to plug into a common 120v plug, I would like to maintain the system completely off the grid.  My system will have the ability to plug into a common outlet should I have the need, but I am hoping that will not be the case.

Our charging system is a little more complicated than just a solar panel, solar charge controller and batteries, we have to somehow charge a 48 volt system from a 12 volt solar panel.  We are space handicapped and cannot put 2 - 4 solar panels on the cargo lid of the WattCycle.  We only have room for one 65 watt panel, and putting up a canopy of two or four solar modules above my head just seems ludicrous outside a carnival parade. 

How then do we plan to charge our system?  I will be using two small 12v AGM batteries with a higher amp hour rating than our propulsion batteries.  The AGM batteries, or charging batteries will receive the solar charge anytime I am riding or parked in the sunlight.  The solar panel will keep the charging batteries at full charge during the day and act as a buffer for power.  By using this AGM batteries and an inverter, I will then be able to create a useful 120 AC volts any time I like.  I just happen to have a 1000 watt inverter in the shop that can easily run the 48 volt charging system that I will use to maintain my lithium propulsion batteries.  Now, I am sure that there might be an engineer out there that is shaking his/her head, knowing that there was a better way to build this mouse trap, but I have not cultivated that brain cell yet.

Sunwize 65 Solar Panel

• The glass surface is impact resistant and allows maximum light transmission
• Polycrystalline solar cells are encapsulated and bonded to the glass in multiple layers of ethylene vinyl acetate (EVA) and laminated with a white Tedlar™ backing insuring long life in severe environmental conditions
• A weather resistant junction box accommodates all wiring methods including moisturetight strain relief connectors and electrical conduit
• Bypass diodes insure reliable operation
• Anodized aluminum tubular frames add strength and durability
• Rated Power: 65 Watts
• Rated Voltage: 17.4 Volts
• Rated Current: 3.7 Amps

Ganz 10 Amp Solar Charge Controller

The charge controller will process the 17.4 volts from the solar panel and automatically charge my secondary batteries as needed.  It will work with lead acid, AGM or Gel batteries.  I will be charging an AGM for this project.  This charger is capable of charging two battery banks should I need and it will auto switch between the banks as needed.  It also has protection for overcharging, reverse polarity and short circuit.

 

Ganz Remote Charge Meter

Monitors both solar voltage & battery voltage, charging current & load current
Displays Amp-Hour, watt-hour charge accumulation and percent of batteries charged
 






48 Volt Charger - Maintains the primary batteries

Searching online for a charging system was like looking for a ripe melon, if you know what you are looking for, you can always shuffle through the mess and find what you need.  In our case, I knew we needed a smart charger that can handle a 48 volt system.  When I say "Smart Charger", I am talking about a charging system that will sense the needs of the battery and  vary both the voltage and the amperage to keep the battery in the best state.  Overcharging and undercharging are both catistrophic to a battery system.  We happened to find a Soneil charging system that met our needs for the right price.


So, to sum up the charging system;

1. The solar panel charges the secondary battery system using a charge controller
2. The secondary battery powers a 120 volt AC inverter
3. The inverter powers a 48 volt DC charger and charges the primary lithium batteries

The inverter will also keep all of my cordless power tool batteries charged should I need.  Just an added bonus.