Hi all

I tried to look in the docs and on the forum but no luck. When I'm running my kettle and there isn't a big supply of solar, I get a slowly blinking red light on my pylontech. Rough calc says it's about 59 Amps (2800/48) and watchpower confirms this. In the data sheet it says recommended discharge current is 37 Amps so I'm obviously over that but the max (excluding spike) is 74 Amps which I'm under in this scenario. So my question is does anyone else experience this and, is it anything to worry about? It's not like I run my kettle often and I understand that this will most likely cause a bigger dip in the batteries than drawing a lower current over a longer period.

 

What do the battery volts drop to?

As per the manual, the alarm will trigger if : 

Quote

a) Temperature: Above 50℃ or under -10℃, the battery could not work. Solution: to move battery to the normal operating temperature range between -10℃ and 50℃ 
 
b) Current: If current is greater than 100A, battery protection will turn on. Solution: Check whether current is too large or not, if it is, to change the settings on power supply side. 
 
c) High Voltage: If charging voltage above 54V, battery protection will turn on. Solution: Check whether voltage is too high or not, if it is, to change the settings on power supply side.  
 
d) Low Voltage: When the battery discharges to 44.5V or less, battery protection will turn on. Solution: Charge the battery for some time, the red light turn off  
 
Excluding the four points above, if the faulty is still cannot be located, turn off battery and repair.

 

That's what confuses me, everything was in acceptable range. And with d, it says battery protection will kick in which does not happen, the thing just merrily chugs on with the blinking red light.

Theo

I hate to say this then, but you may have a faulty battery. If I were you, I'd get it checked out by the supplier.

You may have a faulty cell which when put under load drops volts and triggers an alarm.

On 2020/01/30 at 6:33 AM, TBohnen said:

59 Amps (2800/48) and watchpower confirms this. In the data sheet it says recommended discharge current is 37 Amps so I'm obviously over that but the max (excluding spike) is 74 Amps which I'm under in this scenario

It can't handle 74A for a long time, it can handle 100A for maybe a second according to the manual. Running it for a minute on 74A will probably give you a lot of problems.  From looking at Inverter and Battery recommendations, they normally double up the Pylons to avoid situations like this. Victron recommends a minimum amount of batteries to avoid situations like this:

I would think you need to get another battery..

 

+1 that you need another Pylontech to run in parallel. A US2000 instead of a US3000 may suffice as it would supply steady state current of 25 A. 

That 25A plus your existing 37A = 62A

A cheaper alternative is look for a new kettle with a lower power element 😀

I have the above config as suggested by GreenMan and it works great! I pull a max of 62A (if i put the geyser element on) but usually nothing more than 50A. This is on a 48-50V system

 

Also, I recently bought a Russell Hobbs "Eco Friendly" Kettle. It's either 2200W or 2400W so not sure how true the naming is but it pulls about 48A at 50V. It's only slightly slower than the 3000W kettle though.

 

Running everything off-grid at night so no sun or eskom

Awesome, thanks everyone. You've confirmed my suspicions. That table is very handle @PaBz0r, thanks! I'll get a stove top kettle for now and then just save up for more batteries. So it seems that anything above the recommended 37 amps current is going to go red and is not good.

I'll also just make sure that we don't pull anything strong at night when there isn't any solar, it seems fine (light doesn't go red) when there is enough power coming in. I don't know the internals of the pylontech / axperts + bms well enough but I'm hoping that if the green light stays on we're all good.