just bought a 1981 SANFU electric van

[hasp]

Hi everyone, i just aquired a Sanfu electric van from 1981.

I only found very limited Information about it online,
just this article on barnfinds:

https://barnfinds.com/exclusive-rare-1981-sanfu-electric/

it says something about 17 Batteries and only 24 cars made, in Taiwan,
and it seems to based on an early Subaru Sambar.

My car was bought by my cities technical university in 1981 and has done 800km since then.
it has all the documents, does drive with 6x12v lead batteries in it. mine doesnt seem to have the original battery tray in it,
it looks like someone has built a new one for more regular shaped lead acid batteries at some point, and i think it was last run with 8x12V.

What confuses me is that the motor says 90v on its plaque, but 17x (presumambly)6V batteries would be a 102v system.
i would like to build a LiFePo4 Batterypack for it but dont know about the Voltage, i dont wanna fry the motor controller, which seems to be working. (i just did a first testdrive today, using 6x 12V car starter batteries in variing stages of their service life,
and it only did walking speed. so i reckon the voltage is too low)

here are some pictures:

and a video:

[youtube]3DuvoMtT9UQ[/youtube]


So anyways, why this post?

I would really like to keep this funky piece of history alive and also bring it back on the road,
therefor i am looking for:

.) any Information regarding these Sanfu Vans, like operating Voltage for example.

.)Any tips for sourcing brake parts, steering parts, suspension parts for the subaru sambar third generation (1973–1982) van this is based on


thanks in advance,
greetings,
Alex

 

[amberwolf]

Couple of suggestions:

First, test the capacitors on the controller. Many electrolytic caps as old as those will be aren't capable of their original filtering, and may not do the job they need to do anymore, in which case the controller could fail from voltage spikes, noise, etc. If you have an oscilloscope you can check for this on the bus(es) the caps are filtering, and if there is no noise at various frequencies under even heavy loading, the caps are still doing their job.

You can also find the voltage rating on the caps while in there, which will help find a system limit (since it should be well below that rating).

Assuming it is a PWM motor controller, then if you can read the transistor (and diode, if any) numbers, we might be able to find specs for those, which will also narrow down the voltage limits.

Any other active electronics in there will also have voltage limits, so if it has a low voltage power supply to run PWM generator, etc, it may help figure out what to keep the system under.

The contoroller looks hand-built, so it might not be a commercially-available unit with specs (even if you could find them after this long).


(also, noting down all parts values and taking detailed photos of wiring/PCBs now while it is still working will help you repair it if it does ever fail).


For the motor voltage, it can generally take quite a lot more than it's rating--the two primary limits are the brushes will heat up more with higher voltage, wearing faster especially at higher loads, and the motor (assuming brushed) will have a speed limit at which point the commutator will come apart and fly off the armature. This is usually a lot higher speed than it would ever see in normal use, but since you don't know what speed the van was intended to go from the electric conversion (vs it's original ICE design speed), your safest check is to see what RPM the motor is rated for on it's nameplate, and then check that worst-case it won't exceed that in any of your use cases (adding a tachometer if necessary).

Note that if it is a series-wound brushed motor, don't try running it unloaded at anywhere near it's rated voltage, as it has no way to limit it's RPM and can easily spin fast enough to grenade the commutator. Series-wound motors can be tested unloaded only at much lower voltages, or very low throttle settings, because of this. When loaded by the drivetrain, even offground, it is generally safe enough, but if the motor is not connected to the drivetrain, be careful.

 

[PaPaSteve]

Typically a brushed motor can be slightly over volt-ed without much trouble.
Sometimes a fan for forced air cooling to the brushes is a good idea.
Looks like a fun project.

 

[hasp]

Couple of suggestions:

First, test the capacitors on the controller. Many electrolytic caps as old as those will be aren't capable of their original filtering, and may not do the job they need to do anymore, in which case the controller could fail from voltage spikes, noise, etc. If you have an oscilloscope you can check for this on the bus(es) the caps are filtering, and if there is no noise at various frequencies under even heavy loading, the caps are still doing their job.

You can also find the voltage rating on the caps while in there, which will help find a system limit (since it should be well below that rating).

Assuming it is a PWM motor controller, then if you can read the transistor (and diode, if any) numbers, we might be able to find specs for those, which will also narrow down the voltage limits.

Any other active electronics in there will also have voltage limits, so if it has a low voltage power supply to run PWM generator, etc, it may help figure out what to keep the system under.

The contoroller looks hand-built, so it might not be a commercially-available unit with specs (even if you could find them after this long).


(also, noting down all parts values and taking detailed photos of wiring/PCBs now while it is still working will help you repair it if it does ever fail).


For the motor voltage, it can generally take quite a lot more than it's rating--the two primary limits are the brushes will heat up more with higher voltage, wearing faster especially at higher loads, and the motor (assuming brushed) will have a speed limit at which point the commutator will come apart and fly off the armature. This is usually a lot higher speed than it would ever see in normal use, but since you don't know what speed the van was intended to go from the electric conversion (vs it's original ICE design speed), your safest check is to see what RPM the motor is rated for on it's nameplate, and then check that worst-case it won't exceed that in any of your use cases (adding a tachometer if necessary).

Note that if it is a series-wound brushed motor, don't try running it unloaded at anywhere near it's rated voltage, as it has no way to limit it's RPM and can easily spin fast enough to grenade the commutator. Series-wound motors can be tested unloaded only at much lower voltages, or very low throttle settings, because of this. When loaded by the drivetrain, even offground, it is generally safe enough, but if the motor is not connected to the drivetrain, be careful.

thank you for that elaborate answer! i do not fully understand (yet) all the tasks you are suggesting, but i will definitely do the capacitor testing bit with the help of a more knowledeable friend

Typically a brushed motor can be slightly over volt-ed without much trouble.
Sometimes a fan for forced air cooling to the brushes is a good idea.
Looks like a fun project.

actually the car has some forced air cooling for the brushes via fan from factory.

the barnfinds article mentions that the other car still has the original 17 batteries in it,
assuming those are 6 volts, that would amount to 102 volt.
that would make a 32s lifepo4 batterypack a near perfect fit.

the car does have an onboard charger which of course is going to have to go,
firstly because its for the original lead acid batteries and also because it has
110v input (presumably for the american market) and i live in 220-land.

but! should i get a 220 to 110 transformer and measure what voltage the original charger gives out to see wether my 102 volt system voltage suspicion (purely based on that barnfinds article) is correct?