Strange charging behaviour

Could be a dodgy connection between charger and battery.

IIRC, the voltage displayed is reported from the MC, but the voltage used to determine charge current is measured internally by the charger.

other possibilities is dodgy line voltage (though that would be more likely to cause the charger to report a fault and shut down).

has it happened before/since?

Matt

As this has only happened the one time at a shared charging point I would suspect it is a voltage fluctuation being the culprit. Maybe one or both of the Think City's had a problem causing this to happen? To be on the safe side I suggest disconnecting the charging cable and finding another place to recharge.

I havnt seen that behavior before but it does look like a supply issue .has it done it at any other supply points.

Looks like a supply voltage fluctuation. The charger will go into a lower power mode when the line voltage drops, otherwise it would try to draw too much current to maintain 1500W out.

Does it happen every time? Does it happen wherever you are plugged-in?

Looks like a supply voltage fluctuation. The charger will go into a lower power mode when the line voltage drops, otherwise it would try to draw too much current to maintain 1500W out.

Must have been quite some drop, because they are on 220V AC in Spain (or similar).

But possible due to the other EV's sucking amps at the same time.

It illustrates how charging could become much more problematic in the future when there are more EV's.

For example, airconditioners now must have a device to prevent them from turning on straight away after a power outage. I think there is a random device in there to spread the sudden high demand over a little while. If the airconditioners (or charging EV's !) all turn back on at the same time, the grid voltage goes to it's knees straight away!

If the airconditioners (or charging EV's !) all turn back on at the same time, the grid voltage goes to it's knees straight away!

grid voltage only falls if your local transformer is heading into saturation.

if the grid as a while is overloaded, grid frequency falls, but not necessarily voltage (the transformers kick up a tap to maintain voltage output0).

most power supplies with PF correction (like the vectrix charger and any "inverter" aircon) shuts down when grid frequency drops below some value (usually 48.5Hz).

frustratingly, this is also true for grid-tie inverters (oh look the grids overloaded, lets shutdown all the solar systems.....).

anyway, back on topic.

another effect of a non-PF corrected charger is "clipping" of the voltage waveform.
so instead of a perfect sine wave, the top is actually flat.
this is due to the majority of the current drawn when the voltage curve is at its highest.

on a non-PF charger, the result of the clipped waveform is reduced voltage on the intermediate DC bus (just after the rectifier).

I would not normally expect this to affect a PFC charger, as there is a boost converter on the input.
however, you don't know for certain how they react until you test it (I haven't really tested out my Vectrix charger yet).

Matt

If the airconditioners (or charging EV's !) all turn back on at the same time, the grid voltage goes to it's knees straight away!

grid voltage only falls if your local transformer is heading into saturation.

if the grid as a while is overloaded, grid frequency falls, but not necessarily voltage (the transformers kick up a tap to maintain voltage output0).

most power supplies with PF correction (like the vectrix charger and any "inverter" aircon) shuts down when grid frequency drops below some value (usually 48.5Hz).

frustratingly, this is also true for grid-tie inverters (oh look the grids overloaded, lets shutdown all the solar systems.....).

anyway, back on topic.

another effect of a non-PF corrected charger is "clipping" of the voltage waveform.
so instead of a perfect sine wave, the top is actually flat.
this is due to the majority of the current drawn when the voltage curve is at its highest.

on a non-PF charger, the result of the clipped waveform is reduced voltage on the intermediate DC bus (just after the rectifier).

I would not normally expect this to affect a PFC charger, as there is a boost converter on the input.
however, you don't know for certain how they react until you test it (I haven't really tested out my Vectrix charger yet).

Matt

Thank you for these detailed explanations, and please excuse my ignorance!

I should not write such things as if I knew what I was talking about....

I should have said: When all air-conditioners and EV's turn back on at the same time, they cause some kind of problem for the grid power supply which can make it hard or impossible to re-start the power supply. (That might be incorrect, too!)

Howdy,
I've had a strange charging pattern lately
I usually charge everyday with a 1hr delay at about 131V charging starts at around 8pm and at 9am the next morning it's still going?at what should be the end of charge, "CO 153" is posted when the dash is on, the charger goes into 5min charging patterns as such:
the dash turn on ( cycling of needle)
the current ramps up to max current then immediately to zero (there might still be some current, but I haven't check on the diagnostic
and the timer counts down from 5 minutes but the fans keep running...
Voltage is around 144-145V temp anywhewre between 19-28°C (depending on the days)
after 5 minutes the dash and fans turn off
5 min goes by with everything off then the whole deal starts again
I usually interrupt this in the morning when I leave for work, but on the weekend if I leave it plugged-in it will go on all day

I've done my regular 2-consecutive deep discharges recently (charger reset) but it hasn't changed anything....
I though it might a problem with the fans (only one seemed to run at times) but both seem to work now and temp hasn't reached critical levels...

Anyone had similar behavior?
Cheers, Marsu

This exact same thing happened to me recently. I was shocked when 24 hours after I plugged it in to charge it was still charging when I went to hop on the bike. It hasn't happened since but it was definitely strange. The battery temp got up to 36 C so I rode it on my regular commute then parked it for two days. The temp was back to 23 degrees so I charged it and it completed like it normally does. The problem I am having now is the end charging voltage is sometimes less that 140V. The lowest end voltage was 137V but recently it was back to 142. I'm nervous about doing any deep charges in case there is some imbalance in the pack but I think I need to do a couple in a row to reset the charger/battery charge.

Any suggestions?

Thanks,
Adam

I think what happens is that the Vectrix charger draws more and more current in an attempt to keep the charging power constant. This then causes a drop in the supply voltage, until the charger reduces the current draw. (It's probably a lot more complicated than that....but what ever the exact explanation will be, I think it is due to the chargers nasty behaviour of just asking for more more more current at a time when the supply source cannot provide enough!)

This is what it looks like with a generator that cannot keep up with the Vectrix demand: