openinverter forum

Yeah.. time for a new project

I found an abondened project for sale, it is a 2013 Estrima Biro 45/60 kmh city vehicle.
Story was that it got stranded in 2014 in Norway after just 450km from new with a broken controller by the first owner.

Bought buy someone in Norway with plans to restore it....
Controllers by the brand of 'Kolektor' from Hungaria got replaced by two SevCon Gen4 modules.
The 48V lead batteries got replaced by a BMW i3module... and then the project stopped for 4 years ...
Owner moved to Belgium, Biro came along and there it was again stuck for 5 years...

And now 9 years later it is in my workshop
Almost new, with just 450km and a lot of goodies te get it on the road again.

As the SevCons can ONLY be controlled by an IXXAT CAN adapter with the correct DVT software this was the first thing to get working.
The adapted wiring from the old Kolektor to the new SevCons was a mess, a blown fuse was found in the dashboard, which is in general not a good sign

Pics or it didn't happen...

That looks like the ultimate mobility unit for those that have difficulty getting around. Looking forward to seeing it's revival story

T1 Terry

T1Terry wrote: ↑Mon Sep 22, 2025 11:11 am That looks like the ultimate mobility unit for those that have difficulty getting around. Looking forward to seeing it's revival story
T1 Terry

My daughter thinks that I'm looking more and more like a retard with first driving in a Th!nk and now this....
Wait until I have tickled the SevCon's to go 80kmh...

The wiring to the SevCon under the seat was a little messy. The crimped pins inside the 35pin AMP connectors were not done properly with the special (and expensive) AMP crimping tool and causing unexpected behaviour.
So I took out all the wiring and rewired the minimal wires for diagnosing the SevCons with colored wiring and made new brackets for the SevCons instead of letting them bouncing around.

The Biro has two 'Proud-Eagle' PMAC wheel hub motors like the Vectrix VX2 and some Govecs scooters have, with UVW encoders.
The two SevCons operate in Master-Slave mode where the Master node1 is having the physical input/output connections and UVW and power cables to the left motor wheelmotor and the Slave Node2 has only the UVM and power cables the wheelmotor and is instructed by the Master over CANbus connection.

After connecting the IXXAT CAN interface and fiddling around with the provide DCF configuration files the units started talking to each other. Unfortunally the UVW encoder wires and motor power cables where connected wrong causing all sorts of errors. Time to take out the oscilloscope and re-align the UVW encoder wires with the M1,M2,M3 motor cables.
The three UVW encoder (only U and V are shown here as my scope only has 2 channels) wires follow each other in 120 degree pattern with a little overlap between each set of pulses. So it is pretty easy to figure out which wire has the U, V or W Hall sensor connected.
After connecting the U sensor and connecting two power cables to the scope and spinning the wheel by hand the accompanying M1 and M2 cable can be found and M3 is the one left over.

Here the U sensor is in sync with the according M1 motor cable.

Added the batteries today, 16 Leaf modules fit in nicely. Might consider seperating two modules for a seperate 14V system and keep 14 modules in series to reuse the oem charger at 58V

I converted a view biros here in Amsterdam using cheap Chinese fardriver 450 controllers.
I also use a cheap Chinese off grid inverter to charge 3 catl 180 amp 4s in series@ 43,2 volt.
With a 200 amp jk bms.
The inverter is able to charge ad 40kw (if your 230 is fused ad 20amp)It also gives you 230v ac and has a solar charger for just over 230 euros.
Controllers, and bms are all setup with a android phone. And including wiring done in just one day.
If you need the original controllers from biro i have 6 of them on the shelf.

Best regards Paul

Karstkok wrote: ↑Tue Sep 30, 2025 11:57 am I converted a view biros here in Amsterdam using cheap Chinese fardriver 450 controllers.

Interesting.
How do you drive the speedometer as this signal did come from the Kolektor originally ?

After a few test drives the Biro’s left wheel started to make a cracking sound from the outside. As I assumed it was the bearing I decided to take the wheelmotor apart as the bearing seemed to be replacable.
Luckily it was a generic part and easy to buy locally for €8,50 each, but better quality

Karstkok wrote: ↑Tue Sep 30, 2025 11:57 am I converted a view biros here in Amsterdam using cheap Chinese fardriver 450 controllers.
I also use a cheap Chinese off grid inverter to charge 3 catl 180 amp 4s in series@ 43,2 volt.
With a 200 amp jk bms.
The inverter is able to charge ad 40kw (if your 230 is fused ad 20amp)It also gives you 230v ac and has a solar charger for just over 230 euros.
Controllers, and bms are all setup with a android phone. And including wiring done in just one day.
If you need the original controllers from biro i have 6 of them on the shelf.

Best regards Paul

Goedeavond Paul, wat wil je voor een originele controller hebben?

I don't use the original speedometer. I have a fardriver display and a galaxy tab covers the original speedometer. As All elektronic Parts from bro are really expensive. I don't use them. I also use vw id3 modules.

prensel wrote: ↑Wed Oct 01, 2025 6:59 pm After a few test drives the Biro’s left wheel started to make a cracking sound from the outside. As I assumed it was the bearing I decided to take the wheelmotor apart as the bearing seemed to be replacable.

IMG_6506.jpeg

Luckily it was a generic part and easy to buy locally for €8,50 each, but better quality

IMG_6506.jpeg

prensel wrote: ↑Tue Sep 23, 2025 6:38 pm Added the batteries today, 16 Leaf modules fit in nicely. Might consider seperating two modules for a seperate 14V system and keep 14 modules in series to reuse the oem charger at 58V

IMG_6478.jpeg

What BMS are you going to use? I suggest a 200a JK BMS with 2 amp actief balance