just wondering how the powersense would work when you are running a hot water diverter in place, eg Paladin, would think some how you need to make one a priority
Hi Tim.
Priority is effectively managed by configuring the level of export that needs to be detected before starting to charge. We typically recommend that charging only begins once 1500W is being exported, because the slowest possible charge rate of a car is about 1400W.
A hot water diverter would usually activate when there is only a small amount of export, so you wonât see that 1500W level until after the cylinder is fully heated and diversion has stopped. Thus your car will be charged only after your hot water has reached whatever the cutoff temperature is.
Tom
Hi Tom,
We watched the behaviour of our system following the addition of 4kW of PV (now 9kW total) and an Evnex E2. We have a Paladin diverter as part of our installation.
Yesterdayâs behaviour appeared as follows; The Paladin sensed the HWC being below the 40C safety threshold following my morning shower and initiated a 3kW feed into the HWC to address this. I then turned the HWC off to prevent this until our solar was generating >3kW. The low HWC temperature was the result of the Paladin and solar being off line for the 2 days that our upgrade work took, and is the first time in the last 18 months since the Paladin was installed that our HWC has drawn any power from the grid.
On turning the HWC back on the Paladin drew 3kW (from our PV), with the E2 connected to our Polestar2 after midday when the HWC demand dropped once 40C was attained, initially displaying a âWaiting for more Sunâ message. Once our solar generation increased enough to provide 1.4kW âsurplusâ the E2 started charging the car but what happened next was interesting as the E2 seemed to then prioritise itself over the Paladin while there was 1.4kW or more generation occurring with any residual current being mopped up by the Paladin. From what I saw in real time the Paladinâs reaction to its monitoring resulted in mostly less than 100W of export/import occurring whereas the E2 didnât seem to react as quickly as generation fluctuated with a âlumpierâ export/import trail of >2300W.
I guess the E2 âpulling rankâ over the Paladin is to the good as it results in continuity of EV charging which is better for the EVâs battery.
The Screenshot covers yesterdayâs activity. The period of 4kW consumption after 1400hrs is when we discontinued the E2 charge in favour of charging our Leaf via our JuicePoint charger (which we retained for its type 1 socket) and cloud cover dropped generation unfortunately. The consumption peaks before 8:00am was oven use with the one after 8:00am being the brief HWC issue.
Hi there.
I suspect this behaviour is to do with how quickly both of these âtail-endâ loads react to the existence of excess load. The E2 waits for 60s of export at the required level before diverting, so perhaps the paladin waits for longer than 60s?
In terms of lumpiness, I would imagine that this is down to the speed at which the car reacts to a change in offered power. Different vehicles respond at different rates (and I would imagine loads of other factors too like how warm the battery already is, or how full it is). The E2 measures the export at I think 10Hz (certainly sub-second) so is very responsive in what it offers the car, but we have seen vehicles take over 5s to respond, which under patchy clouds is not ideal. It makes me wonder how it works with regenerative braking which surely must fluctuate faster than that!
Regards,
Tom
Hi Tom
Have a paladin and they react almost instantly. From memory talking with the devolper its like a 50th of a second so it scavenges right down to each package of power been used so the power meter records bugger all coming into the house. Watching it when the elemnet capacity is greater than solar input its constantly adjusting to stop any been exported or imported
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Hi Tom,
Thanks for your response. From your comments Iâm more inclined to think that the Paladin âcapturesâ export almost instantaneously as the minimal âspillageâ would seem to indicate whereas the E2 / EV connection is coping with switching lags from both devices compounded by communication delays from both also. I suspect that once the E2 is drawing current continuously the Paladin is being denied the opportunity to join the party once EV/E2 connection is established.
The EV that the E2 is charging is a Polestar2 SRSM which initiates charging within 20-30 seconds from the âhard feedâ from our Juicepoint charger but can take a minute or two when the E2 is connected with surplus solar feed available.
Irrespective of the responsiveness weâre seeing the performance of our PV upgrade has impressed us with the ability of the Paladin, E2 and some manual inputs allowing us to optimise self consumption characteristics extremely well with 90%+ seen on some days.
So far as regenerative braking is concerned this is occurring within the EV by driving the motor and generating electricity back into the battery so independent of the âplug inâ charging system. It seems that the only restriction for this generated electricity is in the case of the battery being at or near 100%SOC, which is a very rare occurrence as charging protocol is to avoid charging fully due to the potential harm this can cause to a NMC battery.
Cheers,
Tony