Hi guys and girls wanted to know what the maximum Discharge for a 10kVA Multiplus 2 with 4 Pylontech US 5000 so 400Ah, it seems to overload L1 if at 7000 which seems low to me i can charge at 8000. Spec says 8000 but im not getting near it for discharge. Anything i haven’t accounted for? System is an ESS with Solar everything connected critical load side of the multiplus 2 and with no grid meter
Temperature can have an effect through derating of your multi and/or batteries.
I’m not sure about your model but I have read elsewhere that polys generally have poor discharge rates.
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cheers but internally when im not sending to the grid they can deliver a without overload, the multi is 48/10000, but the fact its saying L1 overload im thinking its the other side of the multiplus ie grid part of the coil can’t do anymore?
Yip, temperature is one. And what are the loads?
Is the DCL for the Pylon bank 400A or is it lower?
This seems to be at any temp but the test will be in the winter when the multi won’t be hot the max the exhaust temp went to was 42C temp sensor at Multi exhaust, yes the bank is saying on the GX its 400Ah
Sorry to be pedantic. Ah is capacity, DCL is A.
My one bank of pylons is 300Ah but they only give me 148A DCL under parameters.
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You are correct Nick DCL 320A and CCL 320A
Ok but still sufficient for the loads, so thats not it.
Are they overload warnings or alarms?
…and are they transient, if so, how frequent?
So this is purely an export issue? Exporting is less efficient than supplying loads on AC OUT.
@WhiteCitySolar @nickdb no not frequent but every time the waring happens i die a little lol 276
VE.Bus System [276]
Overload L1: Warning 2024-08-30 20:14:06 21s
You soon build up a tolerance.
This can be grid related. I see occasional spurious alarms on mine, have forever, but I know it is grid related, especially under load.
Blasting power into the grid can have a similar result.
If it is just an alarm and transient I wouldn’t worry. I disabled that notification in the end as it ceased being helpful.
You know a real overload has happened when the lights go out… 
lol don’t want to get to lights out lol but the multi 48/5000 could discharge to 4500 without warnings so thought it would get nearer to the 8000 for discharge but load side seen as everything is on the output if a device is turned on will it not get some on the 8000 automagically and the multiplus just derate the grid to the appropriate figure without overload? The problem with me im seeing the notification as a bad thing and it freaks me out seeing it as i frantically battle to change the grid set point but all the alarms have lasted 20 odd seconds im not sure if that’s because im so fast adjusting it or its sorted itself out as it ramps up?
With ramp times, there will always be a bit of a speed wobble while it adjusts to a change in the load dynamics. Running near the limits just amplifies that, before you throw custom control loops into the mix.
These are tough systems, I would not let an alarm concern you, it will just do your head in.
The alternative is to reduce what you are asking it to do, and see if that helps.
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Yeah ill try -6750 and get near to the 7000 as i can but i know 6800 is a no no tried that already
Right so i done a test with my battery maintenance node and set it to -8000 absolutely no warnings but max with losses and house load look like -7400 so ive set that as my max for saver sessions and changed my maintenance to -1000 between 2000 and 2300 as i just want to work them to keep them warm during the winter and maintain the battery SOH just hope my HA automation for the heater and the fans work on the battery temp like i hope it should as that should save me some valuable Wh thought the day
@Daza
This is how long it takes for the system to clear what might only be a mS long load spike. And such spikes rarely, if ever, get picked up on the graphs, even with per-second monitoring. Might help you feel better…
I get them too sometimes - a water pump starting, hey…
Yeah I see similar overload warnings on a 15kVa Quattro (off grid) when a 7kW shower is turned on. They clear themselves so I just disabled the warning alerts, left alarms enabled.
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