kernowsvenski
Well-Known Member
This is all looking very professional. Good work.
Once I had fitted the drive shafts I moved to complete the rear battery box.
Got the high-voltage safety disconnect installed as well.
I missing some photos from the battery box put together but will surely update them once I extract them from my endless pool of photos!
Got the high-voltage safety disconnect installed as well.
I missing some photos from the battery box put together but will surely update them once I extract them from my endless pool of photos!
Attachments
At the same time, I completed the high-voltage contactor box
Installed that as well into the trunk space mount I had built earlier
Currently working to wire up the charger and the rest of high-voltage.
I got time till the end of August to complete this build, so I will be pushing it along rather quickly, if I don't I may have to wait until next year same time due to work commitments.
Installed that as well into the trunk space mount I had built earlier
Currently working to wire up the charger and the rest of high-voltage.
I got time till the end of August to complete this build, so I will be pushing it along rather quickly, if I don't I may have to wait until next year same time due to work commitments.
Alibro
Well-Known Member
Great to see more progress here, all looking good. 
Two things about those contactors.
1. They draw a lot of current therefore tend to overheat, can you build a circuit to reduce the current after they have closed? A simple capacitor and resistor will work but I think some of the guys in OI have been working on a proper circuit to control contactors.
2. They fuse together for fun if you get the precharge timing wrong. Don't ask how I know.
However it is easy to miss if it happens so be careful to monitor them and ensure they always open.
Will you have DC fast charging?
Two things about those contactors.
1. They draw a lot of current therefore tend to overheat, can you build a circuit to reduce the current after they have closed? A simple capacitor and resistor will work but I think some of the guys in OI have been working on a proper circuit to control contactors.
2. They fuse together for fun if you get the precharge timing wrong. Don't ask how I know.
However it is easy to miss if it happens so be careful to monitor them and ensure they always open.
Will you have DC fast charging?
Alibro
Well-Known Member
LOL, I've fried more than one but the most recent left me stranded at the side of the road. It was just a silly mistake on my part but these things happen.@Alibro Funny thing is I think I read through your thread where you fried your Precharge resistors
Not fun times I figured
Alibro
Well-Known Member
This is the thread about Contactor economisers
For my build I bought contactors from China with economisers built in but if you want to use yours it is better to have a way to reduce the current.
For my build I bought contactors from China with economisers built in but if you want to use yours it is better to have a way to reduce the current.
Alibro
Well-Known Member
I think they use full voltage to energise the contactors and ensure they close correctly then reduce the voltage to prevent them overheating. You can buy contactors that have economisers attached to the side of them and will do this for you.
A year or two ago I measured the current drawn by the contactors I had to see what they would draw and it was around 700 to 800mA at 14V so around 11W or 12W which is enough to make them warm or even hot and may reduce their working life.
You would need to try yours to see what they draw.
I believe a lot of folk don't bother and just drive them directly but this is not how it should be done.
Alibro
Well-Known Member
7kW would be nice, I'm using the Outlander OBC (on board charger) which is only 3kW.
Alibro
Well-Known Member
You can buy them but they are expensive so it would be cheaper to buy a contactor with the economiser built in.
Some guys use a resistor and capacitor in parallel then connected in series with the contactor.
When you apply 12V (or really 14.4V) the capacitor behaves as a short circuit across the resistor allowing the full voltage across the contactor. When the capacitor charges it goes open circuit so the resistor now reduces the voltage across the contactor.
I don't know the values they use but it shouldn't be hard to work out.
