Controlling other appliances via BMS / on a DALY BMS How does the D I/O input/output work

GuidoVL

New Member
Joined
Aug 26, 2021
Messages
2
Hi everyone,

I'm new on the forum, but as a visitor, I've already learned a lot here, for which many thanks!

But still having some minor problems, this is my question:

- on a DALY BMS How does the D I/O input/output work ? how can you configure it, has anyone done this already, information…​
- OR, Are there other BMS that are programmable depending on e.g. the SOC and able to control external appliances via ... relays … wifi or bluetooth switches…?​

More info. My installation concerns a motorhome with

- 4 solar panels (4 x 140W)​
- SCC: Epever XDS2 4210 (max 100V PV – 40A)​
- BMS: DALY smart 4s 100A/50A. (SOC now: +/- 10 – 95%)​
- 12V 200Ah LiFePo battery (4Pcsx3.2V Liitokala)​
- EPEVER® IP-PLUS series sine wave inverter 1500W​

As a whole, it must ensure that 230V is always available off grid, and the refrigerator (Dometic, absorption type, 200W) is working on the 230V inverter, preferably the entire (sunny) day… (and night … as much as possible.)

(refrigerator works fine on 230V, always. Can switch automatically to gas if 230V goes down. But for > 1.5 days on gas … it stops. Typical for absorption types!)

PROBLEMS.

1. Not always enough sunshine => drains the battery => refrigerator has to switch to gas e.g. when SOC = 30%. Typically at night.

2. This inverter can be programmed to disconnect at 11.3V, (from 10.6 … 11.3), but it is too late: the BMS has already intervened: cell protect at 2.8V, due to an imbalance (other cells 3,0V), the BMS disconnects earlier. Problem ... SCC! (lowering the low volt protect to 2,5V seems no good idea).

3. Actually I want to have a SOC of about 30% at which the inverter has to drop out (and the frige switches to gas).

Are there members out there with the same issue/problem ? And preferably solutions ?

Thanks for reading this far!
 

sokhapkin

New Member
Joined
Jan 1, 2021
Messages
7
I would like to know how the D I/O works too, but my suggestion will be to replace refrigerator with a compressor one.
 

GuidoVL

New Member
Joined
Aug 26, 2021
Messages
2
Actually it is a problem of controlling your energy flows: cutting off appliances that are not important enough to consume the latest energy in a battery. And the only device that knows the SOC is the BMS.
I can imagine that in home battery systems, this is even more important. but it is the same issue.
 
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