During the conversion of the EVBIMMER I came across another BMW 3 Series for sale. As I compared the original car to this new one I found it difficult to remain motivated as the new car just seemed to fit the “vision” that I had in my mind of what my first EV needed to look like.
Because of this More …
Another one?
November 4th, 2008 Filed under: EVBIMMER by adminControl Boards
November 4th, 2008 Filed under: EVBIMMER by adminThere came a time during my conversion that I had to decide how to make my conrol board. After much debate I decided to go with what was cheap and available, wood. The controller that I chose is cooled via the fins on top so I had no need for a metal plate, this made the decision to use wood that much easier.
When laying out your board try to keep the high voltage system separate from the 12V system for safety. Also, please, use wire ties on anything possible. I cringe when I see a conversion with a tangles mess of wires going from component to component. This is not only a safety hazard but it does nothing to help the image of the EV movement.
I have attached a picture of my control board for reference.
EV Heat and Defrost
November 4th, 2008 Filed under: EVBIMMER by adminAlmost all people who convert a car to electricity will at some point wonder what options they have when it comes to providing heat for themselves and their passengers. This is not always a matter of comfort. Often it comes down to safety because moisture that is trapped inside of a vehicle at night condenses on the windows and causes them to fog up.
Most will agree that their are three options.
- An electric heater element that replaces the stock heater coil in the dash
- An electric fluid heater that circulates warm/hot water through the original heater coil.
- A heavy coat and magical “Anti-Fog”
In this post I plan to document my heater installation. For my vehicle I chose to go with option #2, a fluid heater. I chose a commercially available heater made by Zero Start. The engine block heaters can be purchased from many sources such as J.C Whitney but I purchased mine on Ebay. Because of this I received an earlier model of the engine block heater in the 1500watt version.
This version has plenty of room inside the cover to add an additional thermostats that one may require. Out of the box it includes on 120deg Celsius thermostat to provide over temp protection. I plan to rewire this to control the 12V relay that in turn controls the relay controlling pack voltage to power the heating element.
For the high voltage relay I will be using a relay SSR 24-220V DC, 40A. This relay can be sources via Ebay as well but often ships directly from Asia. I was able to find a distributor in the US and ordered directly from them for around $18 shipped.
I currently have this heater installed in my car and am able to get 100 degree heat from my dash vents while only pulling 14amps from my pack. I will post detailed pictures as well as a wiring diagram soon.
Ben
Clutch or No Clutch, THAT is the question!
November 4th, 2008 Filed under: EVBIMMER by adminEarly on in the planning of my EV project I had to answer this question for myself. The simple fact is that the decision can be made based on your personal preference. Why? Well I’ll try to explain it by comparing the two.
Clutchless:
The clutch disk, flywheel, clutch slave and even the clutch pedal are removed. The act of shifting is performed by lifting you foot off of the accelerator and moving the gear selector lever to neutral. Then slowly move the gear lever towards the next gear. As the next gear is approached a device called a “synchro” begins spinning up the gear to match the speed of the input shaft on the transmission. When the speed is matched the lever will seem to “fall” into gear.
To me this does two things. It removes some of the rotational mass, the flywheel, increasing slightly the efficiency of the motor. Second it forces you to change your driving habits by slowing down the act of shifting. This, in my opinion, increases the range of your vehicle.
Clutch(ed):
A conversion that retains the clutch has a degree of additional complexity. This is due to the fact that the clutch disk, flywheel and clutch slave cylinder are retained. Why? The main reason is that the adapter plate and coupler system must be designed in a way as to allow for the required clearances to house all of these additional parts. In contract to the clutchless system the car will still shift in the same manner as before.
“WAIT!” you say? “That should be better right? I’ll be able to drive the car just as before when it had an I.C.E.”
My Conclusion:
On the surface this assumption holds true, very true. In fact it is true, but, I wanted to have all of the help I could get in maintaining my original design goals. With a clutch it seams that you will shift just like before, slowly releasing the clutch, wasting precious energy. Also, shifting up through the gears you will more than likely try to accelerate faster. With a clutchless system you are forced to slow down and change the way that you drive.
This is my opinion and my comparison of the two systems. I share this in the hopes of helping others make the decision when the time comes.
EVICC….. Huh?
October 28th, 2008 Filed under: EVBIMMER by adminOne of the vendors that I used was EV-Supply in Seattle Wa. Carlo was very helpful and I would recommend him to anyone in that area needing a conversion. One of the special parts that Carlo sells is the EVICC. So what is an EVICC?
Well, it’s basically a small, mechanical, computer to control your EV’s high voltage system. It takes all kinds of inputs and uses them as safety interlocks to enable or disable the connection between your battery pack and controller.
With the EVICC the main contactor on my system cannot close or will open when:
- My fuel door is open
- I am in an accident and the inertia switch is activated
- I push an emergency STOP button in the passenger compartment
- My motor has a high rev condition (FUTURE)
When I turn the ignition switch to the first position my negative contactor is closed by the EVICC. The system is not armed until I rotate the switch as if I were going to actuate the starter in an I.C.E car. At that point the EVICC latches the positive contactor and the system/car is live.
Here is a picture of the initial connections to the EVICC.
You can find more information by visiting EV-Supply or downloading the EVICC manual HERE.
Battery Boxes
October 27th, 2008 Filed under: EVBIMMER by adminBattery boxes were constructed using 1 1/4″ X 1/8″ steel angle iron. Many people have suggested using 3/16″ but I found this to be difficult to work with and added unnecessary weight. Each of my batteries weigh 80lbs with a total pack weight of 960lbs. Haveing the weight distributed as near to original is very importand to maintain braking bias so I placed batteries in the front pack with the other six in the rear.
In order to retain as much trunk space as possible the spare tire well was removed and replaced with a sunken batter tray frame. This frame was then lined with a plastic material called “CoroPlast”. This material is resistant to dirt, oil as well as battery acid. The sides of this box were then sealed to this trunk floor for a water tight seal. A cover will be made to contain the Hydrogen produced during charging.
As can be seen in the last image two conduits were ran from the front of the car to the rear to connect the two packs together forming on 144V pack. The material used was a plastic, 1 1/4″ tube, called InnerDuct. This duct is often used to run fiber optic cableing inside of buildings and it very durable. It was fastened to the bottom of the vehicle with plastic hangers using self tapping screws.
Motor Installation
October 27th, 2008 Filed under: EVBIMMER by adminA motor mounting “ring” was made using 1/4″ steel strip stock by rolling it into a circle with a 9.125″ radius. Mounting ears were included to facilitate the addition of mounting arms. This can be seen in the images below:
Batteries!
October 27th, 2008 Filed under: EVBIMMER by adminI researched batteries for some time and honestly they were probably the most difficult decision to make. Mainly because there are so many to choose from. Obviously most of us would choose to use a Lithium Ion technology battery if we could because of their advantages but right now they are really our of the price range of most people budgets.
Because of this my decision would be limited LA or Lead Acid. Lead acid batteries are the oldest of the battery technologies. Because of this they are the cheapest. The down side is that they are justplain HEAVY!
The batteries that I decided to use are the Trojan T-1275. These LA’s are 12V, Deep Cycle with a 5hr amp rating of 120amps per the manufacturer. These batteries are primarily used as traction/propulsion batteries for golf carts and other NEV’s. More information can be found on the manufacturers site:
http://www.trojanbattery.com/Products/T-127512V.aspx
When my batteries arrived from the distributor, Battery Specialists Inc, I began by comparing the delivered voltages. To my delight each battery was within 1/100th of a volt from each other.
I then topped each battery up to ensure a complete charge. The batteries would have to wait a few weeks befor they could be put into use in the EVBIMMER.
Assembly Begins
October 27th, 2008 Filed under: EVBIMMER by adminSeveral of my major parts arrived and I began assembly. The adapter plaste and coupler were ordered from Electric Vehicles America. When ordering you must provide three critical measurements:
- The distance from the face of the transmission to the tip of the input shaft
- The distance from the face of the transmission to the beginning of the splines
- The distance from the face of the transmission to the end of the splines.
Using the measurements an adapting coupling will be designed and they will include instructions for removing your pilot bearing (if required). After collecting these measurements you will send them, along with your transmission clutch disk, to the EVA machinist. In a few weeks you will receive your adapter kit.
Once you have trimmed and cut your adapter plate and mounted it and the coupler to the motor it will resemble the images below.
Component Selection
October 27th, 2008 Filed under: EVBIMMER by adminAfter lots of research I decided on the following components:
DRIVE COMPONENTS
1 FB1-4001A Advanced DC Motor
1 PB-6 Curtis Potbox
2 Albright Contactors SW-200
1 Logisystems 144AFX 120V-144V 750Amp
1 Adapter Plate with Spacers (1)
1 Motor Coupling (aluminum)
1 Motor Mount (10” Pipe Clamp)
BATTERY SYSTEM
1 QuickCharge 144V Select A Charger 10A/110VAC
1 DC-DC Converter 45a IOTA DLS
24 Battery Terminal Protective Covers (R&B)
38 2/0 lugs - Magna lug (32 straight + 6 90 degree)
1 Relay Interlock EVVIC
50 ft 2/0 Cable - 25 ft Black, 25 ft Red,
INSTRUMENTATION
1 PakTrakr 6batt + 6batt remote
SAFETY
1 Littelfuse L25S-400
1 Littelfuse holder
1 KLK fuse & holder - 20 amps
1 Pair Anderson connectors SBX-350
1 Fuseholder (4) - Control Board
1 First Inertia Switch - Auto Shutoff (12V Sys)
BRAKES
1 Vacuum Pump (12V) & Switch
POWER STEERING
1 Toyota MR2 Electric PS Pump (Used)
BATTERIES
12 Trojan T-1275
I purchased these parts through several different vendors to get the best prices. By doing this I saved around $600 off of “kit” prices.