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model T conversion help please

1686 Views 34 Replies 9 Participants Last post by  Duncan
I started with a 23 T where the engine needed rebuild. I was offered this 300 lb caterpillar forklift motor ,sweet spot 1800 rpm ,series wound motor that i have mounted in the car,direct drive no clutch engine plate is shown it came from a 15 000 caterpillar forklift machine. the T nets out at 1500lb with the ice components removed original speed 35 mph at 1500 rpm. the electrics should balance out to 1500 pounds aftermarket disc brakes stop like a normal car.
I have run the motor direct drive to the driveshaft at 750 rpm on a `12 volt battery . I am anticipating 48 volts to give me just over 35 mph of 50 Km/hr this is a much as I wish to go on 100 yr old wooden wheels.
the batteries are nominal 48 volt from a bmw 130i which at 3500 lbs gave a 200 mile range. there are 8 units 4 under the floor as shown and two under the front seat replacing the gas tank ,two under the back seat cushion.
I have watched the videos from benjamin nelson, scotty vw van and garcia vw van.
nelson and scotty are using lead acid batteries.
The motor i got from a forklift mechanic who now being self employed has no time. a second tech said the same thing and a third does not want the liability. i found an octogenarian who has built 4 electric vehicles SLA and does not want the unknown liability of working with Lithium . the new crop of enthusiasts want AC motors regen and computer algorithms.
I have a main contactor, throttle box. 48 volt 12 volt converter throttle pedal and hydraulic brake pedal mounted to the front floorboard.
i bought a forklift that has a suppex motor and controller that are not compatible with a series wound motor.
I am acutely aware of the need for compatible components.
what i need is for someone to tell me what model controller to buy as well the bits and pieces. what i don't want to do is acquire bits and pieces from various sources that are not compatible. the choices are dizzying. i can sorta figure it out but lack the assurance that my thinking is correct.
I am well aware of what i can fabricate but humble enough to admit my limitations.
I live in the niagara falls canada area. [email protected] 905 9888648




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The battery modules are 44.1V nominal. Might want to place the battery box in the engine compartment if there is room. Hanging down under the driveline could be a recipe for disaster even though the box looks to be of excellent quality. You need a 48V dc controller most any will work.Just make sure it is a DC series/PMDC motor controller. You would need a 12s BMS. Your voltage range 50.4V to 36V 4.2V- 3V. I would go 49.2V to 42V 4.1V to 3.5V. You probably don't need all 8 modules. The modelT is for shows/parades? How much range would you need?
later floyd
 

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Discussion Starter · #3 ·
The battery modules are 44.1V nominal. Might want to place the battery box in the engine compartment if there is room. Hanging down under the driveline could be a recipe for disaster even though the box looks to be of excellent quality. You need a 48V dc controller most any will work. Just make sure it is a DC series/PMDC motor controller. You would need a 12s BMS. Your voltage range 50.4V to 36V 4.2V- 3V. I would go 49.2V to 42V 4.1V to 3.5V. You probably don't need all 8 modules. The model T is for shows/parades? How much range would you need?
later floyd
this vehicle is to be my daily driver. I have a source for the controller , bus bar , do not need regen as the disc brakes work like a normal car better than the original T band transmission.
each battery module has a bms I need to climb the niagara escarpment which is 600 ft. therefore i want to go with the max battery capacity. range expected 300 km.
My previous experience is an 1891 morrison reconstruction which i started out as one motor to one wheel chain drive, too much torque and bent the axle. so i converted to a club car transaxle, first golf cart batteries then Li ion chevy volt 48 volt pack. the brakes are on the driveshaft dual chain drive. my optimum speed is 17 km and 90 km range where the club car controller cuts out at 44volts =[SLA] pre programmed ,which is above the discharge of the chevy volt base of 36 volts. range i cannot access. realistically i could probably climb the 600 ft escarpment but not have the braking power to descend safely .i really don't want to risk fate
so my experience is basically golf cart old 48 volt technology. victron monitoring and schauer charging.

my end goal is to build several vehicles either Tor A conversions as an alternative to the horse drawn carriages that my friends are being choked out of existence by animal activists. so this is not only my personal vehicle but a proof of concept for a specific tourist application that i want to have finished by may.
the daily drive as a tourist vehicle would be 50 km only. the bodies would be built by robert carriages of quebec once the frames have been safetied and certified. i am thinking 5 vehicles to make a viable business model. so there is much to be gleaned from low tech old technology. basically we are making a replica of the 1913 ford Edison electric model t your friend t om
 

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club car controller cuts out at 44volts
Most EV even DC series are programmable , a club car controller would be set up for LA so 11V a battery is right for a 4 s12Vpack. you can set the controller for lower voltage cut off with lithium (NMC) modules
so this is not only my personal vehicle but a proof of concept for a specific tourist application that i want to have finished by may.
Liability is a Big Issue once transporting tourists came into the picture.

the daily drive as a tourist vehicle would be 50 km only.
So a 100km range would work.
There are people who can figure out the kWh needed Surely less thana full i3 pack has. @ 3 miles/kWh that is 33kWh just a guess.
@50km/hr the amount of energy required is much less than @100km/hr.

later floyd
 

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You have no compression braking in an EV, so it's a soapbox derby car going down 600 feet - pretty much totally faded brakes and a safety hazard, if not death trap at the bottom with your escarp-go. Your use model requires regen, which also substantially reduces battery size.

All if your choices for your build are horrible. Carry on, eh.
 

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i bought a forklift that has a suppex motor and controller that are not compatible with a series wound motor.
How big is that motor I assume it is a Sepex motor and controller. The controller may have regen and if the motor is big enough That could take some of the load off the brakes. The two Sepex controllers I have both have regen.don't know if it would be enough. Sepex = Separately excited DC motor.
later floyd
 

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How big is that motor I assume it is a Sepex motor and controller. The controller may have regen and if the motor is big enough That could take some of the load off the brakes. The two Sepex controllers I have both have regen.don't know if it would be enough. Sepex = Separately excited DC motor.
That makes sense, except that the motor appears to have been confirmed to be series-wound:
... I was offered this 300 lb caterpillar forklift motor ,sweet spot 1800 rpm ,series wound motor...

I have run the motor direct drive to the driveshaft at 750 rpm on a `12 volt battery .
If it were SepEx, it wouldn't have worked with just a two-wire connection to whatever series motor controller was used, or direct to the battery.
 

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That makes sense, except that the motor appears to have been confirmed to be series-wound:
Reread what I wrote then reread what tom wrote in first post.
he didn't buy the motor in the modelT with a forklift. He bought a forklift with a sepex motor and controller. Apparently after the motor in the model T.
We are talking about two different motors. The one in the model T the series wound motor and the sepex motor in the forklift he bought.
Later floyd
 

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Discussion Starter · #9 ·
The series motor i got from a forklift tech who indicated he would help me through the entire project as he had previously done a ford ranger. NO time available so I am winging it alone. 4 battery modules are mounted under the floor i can add 2 or 4 as needed. The T had notoriously bad braking as it had only a band on the planetary transmission. front brakes were not installable as the front end is light and the centre of inertia moves forward in braking which unloads the rear wheels.
The after market rear disc brakes make it stop safely like a normal car when it had ICE. I am trying to keep weight towards the back.

sorry for the about sepex confusion. the person from whom I bought the forklift knew only that it was 48 volt. My ignorance i think it is a learning opportunity.It will become a future project.
I can use the main contactor for which i am trying to find out what size precharge resistor to use, ??,dcdc inverter ,horn, key switch,300 amp fuse.
tentatively I am planning to use an orion BMS2, Schauer charger, Victron monitor , Curtis controller 48 volt, bus bar, non mechanical FnR??.
essentially this is intended to replicate the very simple 1913 Edison Ford Electric T. Safely reach 35 mph and climb a very big hill.I tried to upload photos and will try again. thanks for the feedback tom
 

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How steep is the hill 600 foot climb in ___ miles/km? a lot depends on the grade
As remy has said you need something more than just your brakes on your car. Imagine you in your car at top of the hill descending and you start rolling downhill how would the brakes fare with a load of passengers?
From a limited search I found out that it can be complicated to implement resistor braking with a series wound motor.
Which is why I asked about the Sepex motor if large enough it could provide part of the braking with regen.
The precharge resistor value can be found in the Curtis motor controller manual. What I have seen listed is 270Ω for 48v controllers.
I would get a larger amp controller so you are not stressing the controller. 400A instead of 300A.
They also include a basic wiring diagram in the manual.
The Orion BMS2 warns against paralleling strings of cells you would have 8 strings of 12s.
Does Schauer offer a lithium compatible charger?
Many if not most programmable Curtis controllers have an electronic reverse.
Later floyd
 

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As remy has said you need something more than just your brakes on your car. Imagine you in your car at top of the hill descending and you start rolling downhill how would the brakes fare with a load of passengers?
He has aftermarket disc brakes.

If they're sufficient to stop a loaded modern vehicle at highway speeds, how are they insufficient for putzing around town, even if it goes downhill?

Non-issue to me. The brakes are probably 10x what's needed.

From a limited search I found out that it can be complicated to implement resistor braking with a series wound motor.
Forklifts generally use "plug" braking, which is putting the motor in reverse (while moving forward). Even my 1969 York forklift, with SCR & Capacitor speed control, has plug braking.

But again, it's a non-issue if he's installed disc brakes on the vehicle.

...

I'm not actually sure what the OP is asking us to give advice on. It seems he has 100% of what he needs to figure this out, and experience with it.

Are you planning on converting it to lithium? Did you want alternative motor sources since your forklift supplier is unavailable? I'm missing the big picture of your request here.
 

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how are they insufficient for putzing around town, even if it goes downhill
he doesn't plan to putz around town well maybe he does but he is planning on building 5 more for his friends who formerly drove horse carriages in a commercial setting (on the Niagara Escarpment) who have been slowly put out of business by animal right activists. And as such needs every potential liability covered. Two disc brakes may be enough I don't know.
Forklifts generally use "plug" braking, which is putting the motor in reverse (while moving forward). Even my 1969 York forklift, with SCR & Capacitor speed control, has plug braking.
Please forgive my limited understanding but I thought that was a last resort type of braking. at 35mph/50kmh that might destroy the controller then again don't really know
Are you planning on converting it to lithium?
The batteries are nominal 48 volt from a bmw 130i which at 3500 lbs gave a 200 mile range. there are 8 units 4 under the floor as shown and two under the front seat replacing the gas tank ,two under the back seat cushion.
Even included a pic of a BMW part no. A search on the BMW part no. showed that they were i3 12s probably the 111Ah modules
later floyd
 

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The Niagara Escarpment is a cliff. It's what Lake Erie falls off of (Niagara Falls).

I don't care if it has carbon fiber discs from a Lamborghini, brakes work by dissipating energy (potential and kinetic) as heat into a mass (the rotors) until the temperature rises to a point where there is no more heat sink to dump into (brake fade), and riding them down a cliff with ZERO compression brake is reckless by design and a massive liability problem, imo. The mere fact that this is now an awareness makes ignoring it likely negligent.

I believe the contraption being proposed, being a public conveyance, also has to be signed off by a PE. Good luck finding one that will sign off on no other form of braking down a 600 foot cliff other than riding the brakes.

And, yes, you can plug brake...down a hill, which means a LOT more/heavier battery, and even more potential energy to dissipate down the cliff AS HEAT.
 

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If he's doing what I saw in Niagara falls, it's a touristy thing up and down a inclined road in a horse drawn period buggy. So factory buggy has no regen and crappy brakes and only a couple horsepower. American side is flatter than the Canadian side overall imho.

When I was in London, saw an example of their 1900's electric carriage in some science museum which might be a better subject for copying

American side might need a DOT approval as a passenger transport vehicle that the horse carriages grandfather around.
No idea on the Canadian side.
 

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Discussion Starter · #16 ·
If he's doing what I saw in Niagara falls, it's a touristy thing up and down a inclined road in a horse drawn period buggy. So factory buggy has no regen and crappy brakes and only a couple horsepower. American side is flatter than the Canadian side overall imho.

When I was in London, saw an example of their 1900's electric carriage in some science museum which might be a better subject for copying

American side might need a DOT approval as a passenger transport vehicle that the horse carriages grandfather around.
No idea on the Canadian side.
The controllers Curtis currently makes Motor Controllers | Curtis Instruments . select series and 48V it will have a list of controllers.
Later floyd
yes thank you Floyd for your unflagging critique it is most welcome and why i joined this group.
i was first considering the curtis 1236e-5621 HPEVS has precharge resistor built in, with regen capability. the previous model claimed it had regen capability but the mosfets kept burning out.[personal communication from someone who had this happen many times.]
it is about $1100.00
on another note my background is building airplanes i have 6 planes in the hangar. have been a member of the Experimental Aircraft assn before internet came into existence. i was mentored and have mentored in return. that was the only way to learn. i knew from the network where to go to shop for what parts.
I joined this group because i have no electrical mentor. I welcome critical discussion because i don't know what i need to know.
I have consulted Orion who is helping with BMS
Schauer with charging,
I spoke with engineers from Siemens, Wilwood, thirdly an engineer who regularly drives his T down the escarpment, and a fellow T owner who has the Wilwood disc brakes on his T.
The engineer with a normal T uses his engine brake and transmission brake with out concern never a problem.
The fellow T owner with the Wilwood brakes takes a steeper hill and has many times used the disc brake alone without concern. He has complete faith in the system from personal experience.
The wilwood engineer tells me the system is designed to stop a 4500 lb vehicle at 60 mph in a panic stop I am 1500 lbs and doing 30 mph. he told me not to worry I am overbuilt .
The siemens automotive engineer explained there are two parts to this discussion. getting the wheels to stop turning on the car which the disc brakes will do without pause.
The weak link is the friction pad where the rubber meets the road. a 30 inch 3 inch high pressure tire has 3 1/2 inch foot print. this is 1/3 the surface of a modern tire. the disc brakes will lock up the rear wheels long before regen kicks in. The combination of regen and disc will stop sooner than the original transmission brake alone. In the end it depends upon friction co efficient. is the road wet or dry sand etc.
i still have to figure what to buy and where. Most grateful to the ongoing critique keep them coming. your friend tom
 

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The siemens automotive engineer explained there are two parts to this discussion. getting the wheels to stop turning on the car which the disc brakes will do without pause.
The weak link is the friction pad where the rubber meets the road. a 30 inch 3 inch high pressure tire has 3 1/2 inch foot print. this is 1/3 the surface of a modern tire. the disc brakes will lock up the rear wheels long before regen kicks in. The combination of regen and disc will stop sooner than the original transmission brake alone. In the end it depends upon friction co efficient. is the road wet or dry sand etc.
You seem to be doing your homework consulting the right people. Locking up brakes is not fun. Maybe go with (440/450-21’s) balloon tires available from 25 on the model T.( yes I had to look up the tire size). these would have a larger footprint and are low pressure tires. About the same over height of the 30" tires

Later floyd
 

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All of your pals are using compression braking. Nobody is throwing it in neutral and riding the brakes down a 600 foot hill. There's no question you can stop from 30 mph. The question is riding the brakes, as if in neutral, all the way down the escarpment and THEN being able to safely stop from 60mph (runaway condition).

Now you are talking about regen in your posting - not with a DC brushed forklift motor. You can plug brake, but that's a bigger battery being carried, which increases the plug braking need, which increases the battery size, which...

Then you have to get back up the hill. More battery needed...
 

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Lets have a quick look at this in terms of the energy that your brakes have to convert to heat and radiate away

600 ft - 200 meters x 10 x mass in Kg - 2,000 joules per kg
60 mph stop - 27 m/sec - 1/2 x 27 x 27 Joules per kg - 364 Joules per kg

In energy terms the 600 ft is about six times as much as the 60 mph stop

In terms of "power" the 60 mph emergency stop should take less than 3 seconds - the descent would take what 10 minutes?? - 600 seconds

So the "power needs" for the descent are about one seventh of the braking needs
for a 700 kg vehicle we are talking about 85 kW for the braking and 12 kW for the descent

85 kW is a very very low figure for power dissipation of any modern disc brake system
I would NOT expect a continual 85 kW to overheat a disc brake system

The standard for a modified vehicle here (NZ) is that it should be able to pull the vehicle up from 60 mph - SIX times in a row without fading
 
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