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Hi from South Yorkshire

Good Morning all

We are a security company based in Doncaster but also have a office in Tetbury in Gloucestershire. We have recently acquired a Twizzy for are response team for use in the Doncaster area as an alternative to our normal response vehicles.

We are finding it a fun experience and hopefully our Twizy will have its wrap placed on and looking the part!

We are currently looking into fitting some LED days lights/response flashing lights, Bluetooth phone system and automatic locking doors!

Hope to speak more soon!


Prosec Uk Team

Just remember - every voltage consuming toy you install will ultimately affect your range - in that I’m also including the lights and wipers!

This isn’t true. Lights and wipers run off of the 12v battery so don’t affect range at all.

Which is topped up from…?

The traction battery! (Until the next mains recharge). Or are you suggesting the EU would allow the lights to dim as your minuscule vehicle battery powering your iPhone, Parrot & Speakers and lights/Wipers?


I may be wrong but I was led to believe that the headlights and wipers do not affect range. I’m aware the 12v is topped up by the traction battery in rare cases, but from what I’d read from the clever folk on here this shouldn’t really affect range as your 12v battery should be getting a full recharge every time you charge the Twizy. Enough so that you can run the lights and wipers without having to worry about the 12v getting low.

As I said I may be wrong, could anyone with a bit more electrical knowledge shed some light on this please? There are plenty of people on here who have modified their Twizys and use sound systems etc.

The 12V battery cannot supply enough power for the lights if on all the time when running between charges. The 12V battery has a rather small capacity that is simply used to keep the electronics running between charges and a buffer.

I cannot remember the exact capacity but the 12V is only about 35amp hrs. Which is a daft measure as it is based on a 20hr rate! Anyway the lights and brake lights will be drawing 12+amps. Which will flatten the battery in less than 20mins. However this is a small amount of power compared to the traction battery and so although it will affect the range it is a very small amount. Or to fudge it - it will take over 40 hrs to flatten the traction battery with the lights, however you recharge every hour and a bit of driving.

None of the figures are correct but approximations to give you an idea.

If like the F1-Twizy you switch to LED bulbs then the 12V battery should supply all your Lighting needs between recharges. So why aren’t they standard?
The the LED lights should last as long as the car and as some of the bulbs are hard to get to they should have been fitted as standard.

One of the reasons I’ll be upgrading to SMD bulbs at he earliest opportunity. I’m also adding a tally light that monitors the aux battery (only). It is simply a tri-coloured LED that goes green/amber/red as the battery is depleted. There’s three wires - 2 direct to the aux battery itself (+/- ve) with the third to a switched +ve on the ignition circuit. This cuts consumption when you are not actvely using Twizy.

My only issue is where to locate it - it’s a half-inch clear dome but I’m looking for somewhere unobtrusive to locate it where it can be seen but not not look ugly!

Just so some folk don’t get lost.
LED = Light Emitting Diodes and are those domed little glass beads.
SMD - Surface Mounting Diodes and are those little yellow squares.

They are basically the same thing except the SMD version last longer in the the vibrations of a car. They are the new version of LED.

The Renault F1-Twizy has SMD Headlight bulbs. However I’m not sure if they are legal in the UK. Happry for all the other bulbs to be LED. Perhaps someone can tell us. Also where to get them from. SMD bulbs are still quite expensive, but compared to the time it take to take the car to the dealers or change the bulb yourself they do work out better value.

A Warning:- On one of the european forums this time last year it was muted that LED bulbs did not work in the rear lighting cluster due the the way the electronics check the circuits. However that may depend only on the type of bulb being used. Last thing we want to do is have to stick extra resistors in line to up the load just to make the LED/SMD bulbs work.:rolleyes:

Okay from some one who should know more. Instructions in the OVMS manual fro the Twizy:-

The OVMS module currently draws about 2.7 Ah per day from the 12V battery,
which unfortunately has only 12-14 Ah capacity on the Twizy. If you do not charge
or drive for more than 3 days, you must charge the Twizy or unplug the OVMS to
avoid deep discharge of the 12V battery! Failure to do this can result in
unrecoverable failure of the 12V battery. If the car does not power up, that can be
due to low voltage on the 12V battery: try charging! The OVMS will send an alert if
it detects the voltage dropping below 11.5V reminding you to charge in time.

So the Twizy battery is a lot smaller then I guessed. The lights will always run/draw power off the Traction battery.

A 1 watt 12v solar panel will sort that. I’d guess a couple of the cheep plug in the charger panels would cope if it’s in the direct sun all day and you don’t live in Scotland like Andy from Twizy Windows. ;o)

Those Accessory batteries look mysteriously like everyone else’s 12v 12ah batteries…

You’d need to wire them direct to your battery with a 2amp inline fuse at the battery end btw, you don’t want to risk a car fire because on of those little bell wires chafes through… a bit of insulation tape on the length of the wires as a bundle wouldn’t go a miss either.

2 of those £7.50 cheep solar panel things producing under 1 watt, you don’t really need a charge controller it’s not enough to cook one of those batteries long term. :slight_smile:

Prosec, I have experience in doing this with Small EV’s, I was doing the very same thing with our EV scooter product 3 years ago. I developed a separate loom for the hands free blue tooth response lights and accessories. I have some great experience of what you want to do. The key is to make it more reliable than the vehicle itself.

If you want to give me a call on 0771 008 6339 I could even put a Twizy bespoke kit together for you and do some costings if you tell me what you want. I can do the development on my own car ready to install on your cars.

I’ve been learning quite a lot about the Twizy and it’s little quirks and ways. The Accessory battery is really only there to run the systems / lighting ect till the DC - DC controller kicks in, that’s 25amps max, the power for accessories has to be weighed against what the systems use and their typical run times. I can work all that out for you and make sure it’s not going to over discharge or leave someone stranded.

Mark :slight_smile: