Just installed my 2nd user enginer 4 kwh kit.

Hi all,

This afternoon I have successfully installed my 2nd user enginer 4 kwh kit. Have tested it and it is all working ok. (phew)

In my brief time owning the prius (only had it for 4 weeks) the avergae mpg in my location which is very hilly (South Wales Valleys) was 44 mpg.

I just completed my first journey as a test run, and covered 8 miles. The average mpg at the end of the journey was 68 mpg.

To be honest I am quite pleased with that result, to increase my average mpg by 65% in our hilly terrain is very pleasing. I am looking forward to learning to use the kit as efficiently as possible over the coming months. (hopefully dont get any reliability issues)

Thanks to all who has helped with any informtion given.

Best regards, Anthony.

 

Hi all,

a small update. After using the system now for about a month, have done some manual balancing, as the balamcing funtion on the BMS 3.3 has been disabled.

Originally, i could get 2.8kwh into the pack, using an electricity monitor to monitor the amps, volts and kwh input.
I was finding cell 2 terminating the converter early, and cell 15 / 16 terminating the charge.
Bled of about 4ah out of cell 15 and 16 at the high end, and pumped in about 6ah into cell 2 at the low end.
The result is now the pack is taking about 3.5 kwh charge.

I am pleased with that, but i am sure i can squeeze alittle more out of it when i get alittle spare time to spend on it to manually balance alittle more accurately.

So far so good, i just hope it remains relatively reliable. I dont mind spending sone time to manually balance now and again, just hoping I dont get a failure.

Best regards, Anthony

 

I am still using the BMS v3.3 but only as a device to trip the converter and charger.

I also have cellogs 8s to monitor as a check that the bms is reporting the correct voltages from the packs.

As the unit was a 2nd user system, and i dont know the relative usage of the packs, then with the little amount of manual balancing i have done doesnt seem to drastic. Also at the moment its a bit of a hobby, not a distracting bind to me.
As we are on 240 volts here in the uk the pack is taking 5 amps current, 989 watts usage when charging. When the charger is tripped by the highest cell the resting cell voltage generally is about 3.4 volts. I am sure I can get that higher, but also i am wary of putting excess voltage into the cells, so i will probably let things as they are as far as high voltage goes.

Thanks for your input. Anthony.

 

Hi all,

Just a small update on the enginer performance.

With the climate getting warmer now in the uk my overall mpg is increasing.

When I first started using the prius with NO kit fitted, where i live i was averaging 46mpg.

As i was getting used to driving it, and having installed a ECT spoofer, and using the enginer kit went to 67mpg during the winter.

Then, after more learning of driving, got 76mpg.

Now that the climate is warmer, and driving more in ev mode and with driving more in regen position, am getting 94mpg . This has been done over my last 75 miles. I am very happy with that to be honest.

The batteries in the kit are pretty much still balanced, although i do manually adjust alittle every weekend just to tinker with it ( and an excuse to get out of the house for a while )

I have also got some cell loggers with relays to trip the charge earlier (before the 3.8v setting on the enginer BMS)

I have ordered a lovely little pcb board with 8 relays on and 8 inputs (the pcb has relays with flyback diode and resistors along with a darlington transistor for each input to trigger the relay) this will be used to monitor each cell, and control the high charge cut off. I shall take a pic of it when it arrives and has been fitted and tested.
I could have purchased a smaller pcb with only 2 relays on, that would have worked, but paid no extra for the 8 relay set up, if i ever did in the future reconfigure my batteries and go down the norms BMS2 route, then the 8 relay set up woild prove very usefull.

I shall update when i get the small pcb fitted and wrking (hopefully)

best regards, Anthony.

 

Update,

forgot to mention, the reason for the little pcb with the relays is to protect the cell logger open collector outputs. As i have found out to my cost, these are delicate little creatures and with the wrong relays or any back emf the cell logger alarm output dies.
So, by using a npn or darlingotn transistor (2 npn transistors inseries) this proetects the cell logger relay output. The pcb i have ordered ( and it was only £12) this has 8 individual inputs for 8 cell loggers if needed to each relay has its own transistors, fly back diodes and resistors all in circuit all ready to work, so if your like me with no experience in electronics, takes the calculations away from making the small circuit yourself.
In additoin, the relays on the pcb are rated 240v/10A or 28v/10a, so ideal for my set up.


If anyone wants any info on this relay pcb board, let me know.

Thanks, Anthony.

 

Hi Jim, thanks for the advice.

I only intend to use the relay board for the cell logger to switch the pcb relay 12v, then the switched output from the pcb relay will operate an additional 25A 240vAV relay to cut the charger. I already have that relay here.
The cell log will alarm, that will trigger the on board relay to output 12v, that output will trigger the 12v coil on the 25A charge relay, switching off the charger, thats how i am going to set p the system. I hope.

Thanks very much for the input.

Best regards, Anthony.

 

Hi again Jim,

it is my intention to install the charger cut off relay to the inlet side of the 240v in power cord.

I have a power meter in this line and when charging it is taking 5 amps at 900 watts of power, on our 240v AC supply.

Would you suggest then actually installing the charger hvc trip relay on the output side of the charger on the DC voltage line then? If yes, can you advice why this methid is better that isloating the AC input voltage. Srry to ask, new to me, not sure of the advantages of either install method.

Thanks Jim.

 

Hi John (sorry for the Jim bit)

I have electrical knowledge but not electronics, although i do intend to learn abit in the near future along with playing abit with arduino. In my days with sony making tv`s they tought me on plc programming for automation processes using Omron plc`s. i`m hoping arduino is easier, i can program ladder logic ok but havent tackled arduino yet, when i get some spare time i shall have a good read on how it works and how to write basic programs

I am a mech eng, used to work for Sony manufacturing in making large CRT tv`s.

I have got the HVC cut off relay housed in a plastic case in the corner of the load area (behind light cluster portion at floor level. This is alseady in circuit waiting for the relay pcb to arrive. The HVC relay has a mech on/off swtich on top and its set to on all the time at the moment awaiting the low voltage circuit to be completed.

I did consider cutting off after the charger, but didnt want to alter the wiring too much. On the 240v side, its only cutting into the power cord and directing the live and neutral through the relay. The earth is continuous around the relay.

I am considering some time in the future if the enginer kit fails and too expensive to repair, i would contemplate altering (or getting new) batteries into 48v banks to 240vdc lke other have dome and make a kit to run with BMS2. I have the skills and tools to do this, and with keeping the banks to 48v keeping it safer to work on (ie 5 banks of 48v batteries in series seperated with anderson plugs)

I would welcome any info on what kind of performace these systems give in relation to the enginer kits. If i can get over 90mpg with my enginer kit, what coiuld i expect out of a system using norms bms2 and a 240v pack.

Thanks again John.

 

Hi John, i had thought about this,

I have the HVC cutt off signal from the relay going througha push button switch and the HVC relay latched upon the pressing of the pushbutton to allow charging. Once the HVC trip signal is given, the relay latches out, and cannot start again until the high voltage alarm has receeded and the push button is once again pressed.
I intend to set the high voltage cut off at 3.5v initially, then check with the power meter device to see how many kwh has gone into the pack, and reduce the high cut off to 3.45v and again check the kwh into the pack, if the kwh is very small (maybe less than o.2kwh) then i shall probable leave it at 3.45, its a case of checking when i get it all working properly.

Thanks again John.

 

Ok, have finally got the system working where the cell logger high alarm cuts off the charger AC via a relay.

What i have got is a pcb with 8 12v 10A relays with protection for input devices like arduino outputs and open collector outputs, the protection is in the form of fly back diodes and a darlington trnasistor for each relay. You will see a pic of the pcb along with a schematic of one relay and the shematic for the cell log open collector.

The relay pcb only cost £12 delivered, i couldnt buy the parts for that never mind assemble and solder them into a breadboard. I bought the board with 8 relays on it, in case i mod my system in the future. Relay pcb`s were available from the supplier with 2, 4 or 8 relays fitted.

The cell log open collector output mus have a 10k resistor fitted inline from the output to the input of the pcb with a +12v supply. The diagram will show what I mean.

Additionally i have drawn a diagram of how i have wired up my system, may be of use to you.
It has worked now for 5 charges and works as it should.

I am really happy i have now got it working. Note, I have not connected up the black wire from the cell logger alarm port. The alarm port open collector opens internally to neutral to cell 1 -ve (so i have read). It works anyway.

Please feel free to comment, or if i can help in any way please ask.

Additionally, just got past the 100mpg mark, very pleased with that with an enginer kit. Averaged this for the last 140 odd miles. really loving the prius and am getting hooked on projects for it, wouldnt mind in the future upgrading and fitting a system like john`s with a duionomite.

Thanks, Anthony.

 

Hi 2007blueprius,

i was in the same position as you, then a 2nd user enginer kit came available, i weighed up options, and decided to buy the kit, as it was so cheap, couldnt buy the realforce batteries for the price i paid for the kit. Alwayas a chance when buying 2nd user that there may be issues with something but thats the risk of buying used.

Ok, my driving is only small local journeys, and the enginer kit is ok for this type of running, even in ev mode i can do most of the journey using very little or no gas. The enginer bms balancing function has been in the OFF position since new, which is recommended, so knowledge of manual balancing is required to get the best out of the pack.

The converter is the main restriction though only allowing in my case 12 amps output into the prius battery, but as my journeys are so short this is not too much of an issue for me personally.

Now that i have run this system for around 7 months, and really like the ev driving, and not putting much gas in the vehicle, I am considering another mod, where i may re-configure the batteries from 16 cells at 48v to 72 cells in series (have to buy another 4 cells as i have already got 4 spares) to make up 230vdc and use a plug in supply used controllers or buy norms bms2, this will take away the 14 amps max issue. Again this is done elatively cheaply, i can reconfigure the batteries myself for littl cost, just alot of time.

There is no BMS (battery managemtn system) then, but will control it with mre cell loggers with the relay board i alreadfy have maybe with another additional charger relay as a fail safe. I do though have to source a charger, as the 48v one i have will be of no use.

I can then try to sell the converter and charger to recover some of the costs outlayed modifying to the newer and hopefully better system.

I do not regret buying the enginer system, but it has taken quite some time in learning and balancing manually the cells, fortunately, time and patience i do have, and that isnt costing me anything (other than some frustration).

The way i looked at it, for the driving that i do, to try to get as much ev use as possible, this was the best way.

Car was £3200 (2004 gen2 prius with 62000 miles full service history one pevious owner, very good condition)
Enginer kit £1250
Cell loggers and relay board plus additoianl relay £50

so for £4500 I have nearly acheived my goal, (as much ev driving as possible with my driving journeys ) without a massive price tag, I was looking at a new EV like the mitsubishi imiev, or nissan leaf, they are dropping in value here, Leaf is £15000 with 5000 miles, the imiev sells for £10000, again 5000 miles, if i get a small windfall, i shall definately sell the prius with the kit and buy a full ev but that is when they either drop in value to around £6500, or i get a really good offer for my prius.

Hope this helps you in some way.

best regards, Anthony.

 

Well, as far as electricity goes, I have a 4kw solar array, so getting most of my ev driving for free for about 8 months of the year, after that got to buy it at 15p per khw. I,m not In this as a tree hugger or to be super environmentally friendly (I could lie to you but that's the truth), for me it's about the spiralling costs of motoring here in the uk, with petrol at £1.40 per litre or 9 odd dollars, it's getting so expensive it's a joke. This was the most cost effective way to get as much ev miles without spending a small fortune on a modern ev with lithium batteries.
The engineer kit will get you 80 mpg easily, and with driving like miss daisy close to 100, if your journeys are local.
The other methods, ie, norms bms2 and plug in supply do send fake state of charge commands to allow more ev miles and are not limited to 14 amps so are easier to live with ( I hope) as I will probably go this route myself shortly.
I am an mechanical engineer by trade and looked at this as a hobby and project to get me knowledge on the technology and learn how the batteries cycle, which has been good to learn.
I have enjoyednthenexperience and don't regret it at all. And of course saving money, in the last 13 weeks I have only used £34 of fuel. That is a massive saving for me.

LPG is also expensive here and a kit installed here is around £1500, there a very few lpgmfillingnstations and of course you still have to buy the LPG, whereas most of my electric I am generating myself, as a guide I have generated 240 kwh of electricity in the last 9 days, plenty enough to charge the prius multiple times per day.

Best regards with whichever route you choose.