What plug

[geekygrilli]

Hi

Quick question...

What plug do people generally use for charging? Do you use a normal 3 pin 13A plug?

I have some round 16A plugs and sockets (industrial ones) I was gonna use a male one fixed behind the fuel filler flap, then make up an extension lead with a female 16A socket on one end and a male 13A 3 pin on the other.

Does that make sense?

I would wire in 16A sockets in my house and work, but what if i need to charge whilst out and about?

What do teh NCP car parks in London have available?

So many questions!!!!

[electricvehicles]

Sounds good to me

[EVguru]

It's good form to use the 16A IEC309 since it's rated for outdoor use, you can always carry an adaptor to the domestic 13A.

As an aside, a very neat charger interlock (stops you driving off whilst plugged in) was used on the Skoda Elmo. A NO relay contact is wired in series with the igntion switch feed to the main contactors. The relay coil is wired from the ignition feed to the earth pin of a socket mounted where the charge cable is stored. In order to energise the relay, you have to plug the loose end of the cable into the socket (the charger should be earthed to the vehicle frame).

[geekygrilli]

Now that sounds like a good idea - or I could have a switch on the fuel filler flap - no ignition at all if the flap is open, which may be easier for me.

Also, the way I have it wired I will have the batteries connected to the controller still whilst i charge, obviously with te controller 'switched off' is that OK?
I presume it is, because it doesn't say it isn't OK anywhere in the manual. Its and Electrofit Zapi H2600.

[aminorjourney]

You know, the CityStromer that Dennis at Reap Systems has also has this interlock.

I use a 16 A connector along with arctic grade cabling. I would recommend the 16A plug as it's waterproof. Then if you want you can make up a very short adapter plug going from 13A plug to a 16A socket. So far I've never had any problems with charging using this combination. Obviously make sure you use the 16A "Blue" connector - one rated for 240 VAC. There are also yellow plugs which are 16A but only 110 Volts, so double-check the rating before you buy.

Nikki.

[EVguru]

As far as I'm concerned, no it's not OK, or at least not ideal.

In an ideal situation you have a contactor on the negative side of the controller that comes on with the ignition. You have relay on the positive side that connects the controller to the battery via the precharge resistor (this protects both the filter capacitors and the contactor from the very high inrush current) that also comes on with the ignition (some people built a latching circuit that requires using the start position on the ignition key). On the Grizzly controller in my Scirocco and the Alltrax on my bike the controller then turns on the positive side contactor once the precharge is finished. In the absence of an automatic control you can do it manually (put a voltage gauge accross the controller and close the final contactor when it stops rising), or build your own circuit (intelligent or 'dead reconing', i.e. just a time delay).

Just adding in the negative contactor means the controller is not powered from the battery whilst on charge, but you can have a leakage path between the battery pack and the vehicle frame via the motor (carbon build up). This means you can't charge from an earth leakage protected outlet (and you should really).

[EVguru]

All the IEC 309 connectors are rated to about 900 Vac, but there is a convention as to what voltage they are used on.

Purple; low voltage (usually 24V)
Grey; low voltage
Green; low voltage

Yellow; 110V

Blue; 240V

Red; 415V

They 'key' is in different positions so you can't mix the colours.

I prefer to use yellow arctic flex rather than blue (which would meet the convention) because it shows up better when you've got it drapes accross paths etc.

[geekygrilli]

OK, I'll put a contactor on the -ve side of the 96v, switched by the ignition and running off the auxiliary 12v battery.

I've got a load of 48v contactors, off the forklifts round the corner, but s'pose I'm gonna have to get a 96v one now.

Eh, confused myself, does the rating of a contactor mean the voltage to switch, or the voltage it 'contacts'?

With regards to plugs and sockets, i have loads of the red 415v ones. Will I get in trouble with anyone for using these? They are all in perfect order, and seems a waste not to use them.
Also red is a sportier colour - so it will make my car go faster, obviously

[geekygrilli]

Ah - i spoke to Albright this morning, and now understand what the voltage means - its the excitation voltage for the contactor.

I have ordered one which is excited by 12v (continuous), and will be triggered with the ignition key. This will switch teh negative 96v to teh controller.

So now with the ignition off, the is no power to the controller and the batteries can be charged.

Pushed my total cost over £2000 now

[EVguru]

If you're using Albright SW200s then the voltage written on the contactor is indeed the nominal coil voltage.

There are three coil ratings available, though Allbright don't seem to make the information readily available.

1. Continuously operation.

2. Prolonged operation.

3. Intermittent operation.

The difference is the strength of the return spring (and therefore resistance to welding shut).

The intermittant is rated for 15 minutes and the prolonged for 1 hour.

Since you almost never drive an EV for over an hour, you can easily go for the prolonged version.

I'd always go for the intermittant version and use a coil economiser. You need much more current to get a contactor to pull in, than you need to hold it there. There are few ways to build coil economisers. One very simple type uses a resistor in series with the coil to limit the current (drop the voltage) and a capacitor in parallel with the resistor that hits the coil with full current whilst the cap charges. Another way of doing it is to use a contactor with a microswitch. In this case you wire the NC contacts accross the series resistor. The best coil economisers are a PWM drive for the contactor coil.

There is a second voltage rating for the contactors, based on their ability to extinguish an arc. The Allbrights are rated 48v, or 90v with magnetic blow-outs (They used to be rated at 120v, but they changed their test equipment).