it is out of audio topic but maybe some electrician expert can help me.
I live on Germany here we have 3 phase power star with center neutral to ground,each phase to neutral 230v and phase to phase 400v. max allowed current per phase 20A
unfortunately I have an electric car that can charge 7kw 230v 32A monophase no 3 phase
I could slavage 2 toroidal transformer 230v 230v 7kVA from solar inverter.
so I wired primaries in series connected to phase 1 and pase 2 they receive 400v, 200v each primary up to 20A
secondaries are in parallel they provide 200v up to 40A
electric car charges fine up to 24A but more than. that it stops because the voltage gore below 190v (sag from cables and toroids)
I am fine with that and at 24A all works fine.
To avoid the undervoltage cut off I added a third transformer at the secondaries of the 2 big toroids to increase the voltage from 200 to 220v
it is a 1KVA EI transformer 230v 24v 40A connected as autotransformer.
I get 220v the car charges up to 20A but if I increase the amps then the loading cable device (the one that tells to the car ar what amps it has to charge) makes a reset, screen goes dark and more strangely after a few seconds the 20A circuit braker at the primary (400v) side, trips. I reproduced this 3 times.
I suppose that maybe the loading cable device RCD senses a loss to ground, my EI transformer was lying on moist soil, I could understand a reset of three charging device
but why is the circuit brakes tripping?
hos is it possible that more than 20A are flowing for an instant? peak overcurrent?
I live on Germany here we have 3 phase power star with center neutral to ground,each phase to neutral 230v and phase to phase 400v. max allowed current per phase 20A
unfortunately I have an electric car that can charge 7kw 230v 32A monophase no 3 phase
I could slavage 2 toroidal transformer 230v 230v 7kVA from solar inverter.
so I wired primaries in series connected to phase 1 and pase 2 they receive 400v, 200v each primary up to 20A
secondaries are in parallel they provide 200v up to 40A
electric car charges fine up to 24A but more than. that it stops because the voltage gore below 190v (sag from cables and toroids)
I am fine with that and at 24A all works fine.
To avoid the undervoltage cut off I added a third transformer at the secondaries of the 2 big toroids to increase the voltage from 200 to 220v
it is a 1KVA EI transformer 230v 24v 40A connected as autotransformer.
I get 220v the car charges up to 20A but if I increase the amps then the loading cable device (the one that tells to the car ar what amps it has to charge) makes a reset, screen goes dark and more strangely after a few seconds the 20A circuit braker at the primary (400v) side, trips. I reproduced this 3 times.
I suppose that maybe the loading cable device RCD senses a loss to ground, my EI transformer was lying on moist soil, I could understand a reset of three charging device
but why is the circuit brakes tripping?
hos is it possible that more than 20A are flowing for an instant? peak overcurrent?
I would use a 3 phase 8 - 10kvA used transformer from a factory or look online for one.
415volts 3phase to 240volts single phase is your quest.
If you go between just two phases, there will be an imballance on the 3rd unused phase. That could cause the breaker to trip.
415volts 3phase to 240volts single phase is your quest.
If you go between just two phases, there will be an imballance on the 3rd unused phase. That could cause the breaker to trip.
3 phase to 1 phase is nearly impossible to obtain it requires a rare special transfo I forgot the mane.
yes a single 400v to 230v 10kva toroida ransformer would be ideal but expensive.
it isn't the inbalance that trips the breaker, it is a kind if current peak caused by the car with the added autotransformer
yes a single 400v to 230v 10kva toroida ransformer would be ideal but expensive.
it isn't the inbalance that trips the breaker, it is a kind if current peak caused by the car with the added autotransformer
Three phase => DC => single phase. However, don't you think it's better to use DC charging instead ?
Why 50kW ???
Your car takes 7 kW while charging and batteries take DC so all you need is a 7kW DC supply, proper voltage and current as needed by batteries.
Your car takes 7 kW while charging and batteries take DC so all you need is a 7kW DC supply, proper voltage and current as needed by batteries.
maybe the on board charger can take 300v DC at the input. it is an SMPS in any case AC is transformer in DC by a sort of rectifier, maybe mosfet controlled?
But I sont want to test feeding DC if it burns, a new one costs 7K
impossible to charge the batteries directly with a DC charger, the DC outlet on the car needs can bus communication so that the car BMS can pilot the charger
But I sont want to test feeding DC if it burns, a new one costs 7K
impossible to charge the batteries directly with a DC charger, the DC outlet on the car needs can bus communication so that the car BMS can pilot the charger
To my knowledge 3 phase to 1 phase conversion is not possible, only 3 to 2 phase (with the LeBlanc or Scott transformer). 2 phase has 90 deg phase shift and would not help.
Only option i see (without meddling with the charger) is to use a single phase 400V isolation transformer between 2 phases.
But better to get permission from your power supplier first, otherwise all betts are off (in case your house burns down, for whatever reason)..
Also, i find it strange that there would be 1 phase, unless this charger intended for the american market, where they have one phase center tapped
120-0-120V transformers giving 240V between L1 and L2.
Without circuit diagram to risky to do anything, try to get one.
Only option i see (without meddling with the charger) is to use a single phase 400V isolation transformer between 2 phases.
But better to get permission from your power supplier first, otherwise all betts are off (in case your house burns down, for whatever reason)..
Also, i find it strange that there would be 1 phase, unless this charger intended for the american market, where they have one phase center tapped
120-0-120V transformers giving 240V between L1 and L2.
Without circuit diagram to risky to do anything, try to get one.
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Tripping could be because it is actually 230V(or whatever) american style centertapped, and some parts are fed from L1 or L2 and N, the neutral midpoint.
Also, feeding 50Hz into something supposed to work at 60Hz could be a possible problem.
Also, feeding 50Hz into something supposed to work at 60Hz could be a possible problem.
I live in Germany and all gear and car are designed for 230V 50Hz
I already use for monthes (and it works) the 2 big toroidal transformers 1:1 with primaries wired in series fed between 2 phases at 400V max 20A
The secondaries give me 200V with the double of current (40A)
To go more than 24A at the secondary and to avoid the undervoltage protection of the car that trips at 190V (voltage sags to 185V under load), I need to rhise a bit the output of the transformers.
Therefore I added a third transformer wired as autotransformer to give 20V extra, that is when problems start
I will try to draw a schema to post
I already use for monthes (and it works) the 2 big toroidal transformers 1:1 with primaries wired in series fed between 2 phases at 400V max 20A
The secondaries give me 200V with the double of current (40A)
To go more than 24A at the secondary and to avoid the undervoltage protection of the car that trips at 190V (voltage sags to 185V under load), I need to rhise a bit the output of the transformers.
Therefore I added a third transformer wired as autotransformer to give 20V extra, that is when problems start
I will try to draw a schema to post
2 toriids 7kw each alone running fine
note on the screen of the charging cable 188v 18A
if I switch to 24A the voltage drops further and the car refusés to charge
note on the screen of the charging cable 188v 18A
if I switch to 24A the voltage drops further and the car refusés to charge
Have you checked your autotransformer connection actually boosts the voltage instead of dropping it? Are your cables at least 6 square mm?
The cable i can see look more like 16A to me, is it only for the primary of your autotransformer and the high current output is not shown on the picture?
The cable i can see look more like 16A to me, is it only for the primary of your autotransformer and the high current output is not shown on the picture?
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cable.coming out of the blue socket (cee 32A) is 3g6 itt is part of the white charging box I bought new and not modified
on the right bottom of the first picture there is a small fraction of a orange cable that brings the 2 phases 400v to the primaries. you can see also a light bulb used as an irush current limiter at start up
on the right bottom of the first picture there is a small fraction of a orange cable that brings the 2 phases 400v to the primaries. you can see also a light bulb used as an irush current limiter at start up
third transformer is a 24v 230v 1000va EI from an apc ups and yes the voltage was 210v with no load, 200v at 18A
at 24A it charged 5 seconds then the display get dark and 10 sec after the fuse at primary trips
at 24A it charged 5 seconds then the display get dark and 10 sec after the fuse at primary trips
transformer used for adding 20v extra. wired as autitransformer. it has a 230v and a 40v primary I used only the 230v and the thick 6mm2 secondary wires
I would ONLY use Factory (and State Electrical Safety board) approved charging setups, period.
No Ifs and Buts.
In fact I guess this very discussion is beyond what's allowed under Forum rules, sorry
EVs are very dangerous as-is, period, no need to add an extra layer of insecurity.
No Ifs and Buts.
In fact I guess this very discussion is beyond what's allowed under Forum rules, sorry
EVs are very dangerous as-is, period, no need to add an extra layer of insecurity.
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