Vectrix fuse and motor controller bolt sizes
I'm collecting bits for my vectrix lithium conversion and I'm looking for some specific detailed info.
While I'm in there, I'd like to fit a 200A fuse. will this one fit?
http://www.evworks.com.au/index.php?product=FUS-FWH-200B
Also need to buy crimp lugs to connect the battery cable to the controller. What thread size are the controller terminals?
Cheers
Are you going with more voltage too? Or are you going with 125 volt nominal? On my new project I have a place for two each GOULD Shawmut Amp-trap Cat. No. A70P 150 Type 4 fuses one on Negative of pack and one on center of pack. I calculated power and wanted to limit power to 15,000 Watts So 150 Amp fuse would blow at 18,750 Watt, What is nice it is a DC rated fuse. It is the safest fuse I can find. How heavy is your projected Lithium pack? Highest terminal voltage on controller? New charger? VX-1 charger is constant 11 Amp charger timed for 3 hours max by CPU then 3 amp equalization charge. LiFePO4 emulates Pb-acid and NiMH is like Ni-Cads and NiFe cells, all take constant current charging. That is why I ask about 200 Amp fuse.
I just removed the bolts from controller and going to Hardware store to find out. Are you talking of dual ended bolts to hold controller? One is coarse thread and one is finer. I just looked and there is a stop thread. Both sides are metric.
Rusty
I'm collecting bits for my vectrix lithium conversion and I'm looking for some specific detailed info.
While I'm in there, I'd like to fit a 200A fuse. will this one fit?
http://www.evworks.com.au/index.php?product=FUS-FWH-200B
Also need to buy crimp lugs to connect the battery cable to the controller. What thread size are the controller terminals?
Cheers
that one won't fit.
i recommend bypassing the fuse inside the controller (the battery can be wired directly to the output of the fuse as I have done on mine) and placing the fuse somewhere reasonably accessable.
tbh, i have been running without a fuse for a while now, but i don't recommend running without a fuse entirely.
Matt
rusty, i'll be using 42 sky energy 40 ah cells and a simple per cell BMS from EVworks. http://www.evworks.com.au/index.php?category=6
I'll be using the factory charger and using the BMS to cut the mains supply if it detects a cell over voltage. I might use an external, low current charger like "universal freddy" to top up the cells and balance them
normal max voltage will be 153V (bms shunting voltage 3.65V x 42). I think this would be a comfortable voltage for the stock charger.
normal minimum voltage will be 108V limited by the stock controller
Normal voltage under load will be about 3V x 42 126V
Maximum voltage triggering a BMS fault condition would be 4.1V x 42 172V (I don't know what the Vectrix would think about that...)
minimum voltage triggering a BMS fault condition would be 2.5V x 42 105V (I plan on using the BMS to trip the stock battery warning light in this condition... not sure how yet)
out of balance conditions would cause faults between those max and min
The bike will be running stock control so peak power will be stock
I have read that the 125A factory fuse is under rated and that the factory retro fitted 200A ones when the originals blew. I am just wanting to remove the stock fuse while I have the bike apart
cheers
Jason
Wow
Do you have plans for "failure" if something does go awry? I hope it works but deciding on what can go wrong is hard to figure out. Lithium cells are capable of four point something and can go as low as 2.5 or three point something? A large swing . Maybe it be best to go up 20% on fuse first from 125 stock Amp to 150 first? Since going too low on Lithium is bad so have CPU on VX-1 kick out on low voltage on scooter and charge up to 150 max of the bike? Just a thought. Do you know what the input MAX on controller is? I don't want to blow up 2007 VX-1 but don't mind trying to blow my rear wheel motor on my NEW wrecked VX-1 on an old controller actually a VFD really. I read Mik's articles on VisforVoltage and VX-1 motor can develop 20,000 watts peak so that is a lot of Amperes. I sure admire all the work every one on this site does and all the failures and dealing with learning curves. I have a spare charger but NO spare controllers so I don't know working voltage on caps and IGBTs or MOSFETs or what ever does the controlling. I would hazard to guess 200 WVDC is on controller since bike is capable of Regen. The only thing I hate is over voltage circuits using a crowbar circuit. It blows fuses and your Bussman fuse and my Gould fuse is one expensive puppy. What is reason for higher voltage? It will give faster acceleration and yes you will need a bigger fuse for it may just need more current.
Rusty
"What is reason for higher voltage? "
not really phased about the slightly higher voltage. the controller is current limiting, and I don't ride full throttle everywhere.
Plus, hibba has already run this configuration :)
I don't expect to see pack voltages above 153 or below 108V. People have seen 152 on stock packs, with the stock systems.
I've selected 42 lifepo4 cells because the combined ideal charge voltage almost perfectly matches the vectrix charger output voltage and the minimum discharge voltage almost perfectly matches the stock controllers cut out voltage. This makes the BMS cutoffs emergency limits only and I don't expect to see it fire under normal circumstances.
"What is reason for higher voltage? "
not really phased about the slightly higher voltage. the controller is current limiting, and I don't ride full throttle everywhere.
Plus, hibba has already run this configuration :)
I don't expect to see pack voltages above 153 or below 108V. People have seen 152 on stock packs, with the stock systems.
I've selected 42 lifepo4 cells because the combined ideal charge voltage almost perfectly matches the vectrix charger output voltage and the minimum discharge voltage almost perfectly matches the stock controllers cut out voltage. This makes the BMS cutoffs emergency limits only and I don't expect to see it fire under normal circumstances.
you make it sound so easy.
Mate, I sound confident, but I'm actually crapping my self..
The biggest battery I've played with before is a 1100mAh 10 cell nicd pack for my electric plane and that was 10 years ago
Wish me luck
I'll blog the whole catastrophe at visforvoltage for your edification and amusement :)
Sounds "Right" placing fuses in the middle of the pack.In the USA there is Underwriters Laboratory (U.L.) and for forklifts battery pack they call placing fuses on each pack and I did that on my truck too. I used 5 packs of Delphi eight volters making 144 volt pack and every group of batteries went into a Bussman ANN 500 fuse. When the fuses popped I went to Gould Semiconductor fuses of 600 Amps. It is a better fuse for DC circuits. BTW, I only popped two fuses with a 1200 amp controller of the ANN-500 type. So I am not a Pb foot. Not even on my 2007 VX-1. I made a ground fault meter for my truck based upon a Wheatstone bridge circuit and being that there is or "was" a set of 102 cells. It can be center tapped for my old circuit. So maybe a balanced bridge circuit might be nice for you to "Smoke test your new setup"? Call me or email me for more information on that invention if you like. I used it at first to see if any batteries were going south and some did till I got a balanced pack.
Rusty
Lithium cells are capable of four point something and can go as low as 2.5 or three point something? A large swing . Maybe it be best to go up 20% on fuse first from 125 stock Amp to 150 first? Since going too low on Lithium is bad so have CPU on VX-1 kick out on low voltage on scooter and charge up to 150 max of the bike? Just a thought. Do you know what the input MAX on controller is?
i don't know what the input max on the controller is, however, if you are using the stock charger to charge with, then it will always be below the controllers max voltage.
lithium cells only get to as high a voltage as you charge them to.
in practice, a LiFePO4 cell is fully charged once you get it above 3.4v (and current falls to 0.05C).
the controller has a low voltage limit of 108v, or for 44 cells = 2.46v average.
in practice the BMS can sound a buzzer when a cell goes below 2.5v.
just back off the accelerator to keep the buzzer off.
if we could reprogram the controller, you could use the good/bad signal from the cell modules as a feedback loop in place of pack level low voltage limit.
the controller has an input current limit of 275A.
the controllers IGBT's are 600v devices (not sure what the caps are - they will be the limiting factor)
there is no crowbar circuit in the vectrix.
the fuse sizing has more to do with the I^2T rating of the wiring. Thats what it is there to protect, nothing more.
If ever your fuse blows, either it was undersized for the job, or your controller is long dead (in this case long means a second or two ago).
the higher voltage does two things:
increases the speed at which max power point occurs (at present 108v = ~70kmh)
increases the power of max power point, if the controller is operating in battery current limit)
Matt
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i don't know what the input max on the controller is, however, if you are using the stock charger to charge with, then it will always be below the controllers max voltage.
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Matt
Don't forget there were several reports of Vectrix chargers NOT terminating charging as required. That could potentially cause some nasty fireworks!
I do not know if it is any worse with your prospective Li cells than with the stock NiMH cell, but at least the stock cells have a pressure valve to prevent explosions.
that's where the EVworks BMS comes in.
The if a cell top control module detects a cell over 4.1V, it will break the trigger circuit for the master control unit. This trips a 240V contactor that I will route the power for the charger through.
Worst case, if every cell hits 4.1V at the same time the pack would be at 172.2. I don't know if that is going to be a problem for the Vectrix systems.
The Lithium cells also have pressure relief valves
If you go with 42 cells, you are going to use Lithium charger? I thinks antiscab mentioned something about stock charger not getting up to enough voltage? They are two different technologies. One is constant current terminating voltage and the LiFePO4 is usually three stage constant voltage and current preset and going to a third step. With help of management system.
Unusual arrangement, 42 cells, so what charging technique are you go to use?
And another thing. How is scooter computer going to measure miles remaining? And "Charge time"? Maybe any other parameters?
Rusty
I plan on using the stock charger like hibba has already done.
The stock instruments communicate with it so it is easier to leave it all the same.
It just means I'll actually achieve estimated range :)
I might use a small auxiliary charger weekly to ensure the pack is balanced
What will happen if / when the stock BMS decides to do an EQ charge with the Lithium pack you plan to install?
I imagine that it would fill the pack until the evworks bms detected a cell at 4.1V and turned off the power. I wonder if the charger would balk at excessive voltage or low current first?
I don't have an EQ program on my bike. I don't intend to either, unless the supplied current can be dropped to 600mA.
I imagine that it would fill the pack until the evworks bms detected a cell at 4.1V and turned off the power. I wonder if the charger would balk at excessive voltage or low current first?
I don't have an EQ program on my bike. I don't intend to either, unless the supplied current can be dropped to 600mA.
I think 1.5A is the lowest that the stock charger can provide, but I might be wrong.
I've read that elsewhere too mik
But I'm sure Ive seen 10km/h in either the Tr or EC stages of charge.
I want 600mA because that is the shunt capacity of the EVworks control modules. Using that would add another layer of protection from over charging the cells
VX-1 charger is constant 11 Amp charger timed for 3 hours max by CPU then 3 amp equalization charge.
Rusty
Nope, the VX-1 charger is a constant power charger for bulk charging. 1500w. so at a pack voltage of 120, the charger delivers 12.5A and modulates down as the voltage rises to 10A at 150V. I don't think there is a ceiling on the charge voltage. The Bulk charging isn't terminated by a timer. The charger feeds in the same number of Ah consumed during running, plus some amount to compensate for self discharge to a maximum of 33Ah (including the EC phase, I think)
Matt, what a good idea :)
I like how the factory pack splits in to 3 low voltage parts tool free. I think this is a nice safety feature and I'd like to replicate this in my lithium cell set up. A tool free fuse holder in the middle of the battery pack would split it in half at least.
Any reasons why this isn't a good idea?