Recent Posts

1

Midnite DIY Series / Re: MN3548DIY battery current

« Last post by ewilhelm on January 19, 2022, 09:00:08 PM »

And, here's more, hopefully helpful:

Output source: UTI, Charge source: OSO
PV current 12.2 on MidNite, 8.8 on ammeter
Battery current 12 on MidNite, 9.4 on ammeter (different battery without a display on its BMS, so no third data point)

Output source: UTI, Charge source: SNU
PV same as above (consistent, sunny day)
Battery current 25 (hitting the combined max charge current) on MidNite, 22.2 on ammeter

Seems like the "lost" current is related to the PV as current from the Mains through the inverter didn't change the offset between the MidNite's current and the ammeter's current.

2

Midnite DIY Series / Re: MN3548DIY battery current

« Last post by boB on January 19, 2022, 08:07:08 PM »

The negative battery and negative PV are only connected to the inverter/charger's terminal blocks. I have not connected them to each other.

OK, great !   Just thought I would check.

We are talking to SRNE to get this corrected.   Maybe it is just a software update or an adjustment  ?

boB

3

Midnite DIY Series / Re: MN3548DIY battery current

« Last post by ewilhelm on January 19, 2022, 04:52:31 PM »

The negative battery and negative PV are only connected to the inverter/charger's terminal blocks. I have not connected them to each other.

4

Midnite DIY Series / Re: Heart broken

« Last post by boB on January 19, 2022, 02:18:47 PM »

Midnite,

I am interested in the 24V DIY but would like a higher PV voltage threshold. are there any plans to upgrade this or should I wait on the split phase variant to have a higher PV input voltage. Although I really need it now and not a year from now. 

Guessing here, Dan...

For the DIY series, unless SRNE themselves make a smaller All In One (AIO) hybrid inverter/charger, that may well not happen ?

They will change some things for us but that is something that they would most likely need to change for their whole product line.

5

Midnite DIY Series / Re: MN3548DIY battery current

« Last post by boB on January 19, 2022, 02:14:37 PM »

I thought of an idea for this wrong current reporting for both PV and battery current.   Maybe....

For the situations where the currents are measuring wrong, are you sharing a common negative wire for battery AND PV ?

If the inverter/charger measures current on the negative legs only, then it may be necessary to run separate PV and battery negative wires to the DIY3548DIY.

Does the documentation say anything about this ?

boB

6

Midnite DIY Series / Optimal charge settings for LiFePO4

« Last post by ewilhelm on January 19, 2022, 09:53:40 AM »

What charge settings are optimal for my setup?

I have a 48V 100AH LiFePower4 Battery by EG4 and a JK48V100 100 AH LiFePO4 Jakiper Battery that I plan to run with 2 kW of solar and a MidNite Solar MN3548DIY Inverter/Charger. The Jakiper arrived first and has been operating for a week (replacing flooded lead acids that ran fine for months), and I plan to add the LiFePower4 in parallel shortly.

I read the following thread about float charge for LiFePO4:
https://diysolarforum.com/threads/float-lifepo4-or-not.27417/
and am asking a similar question to ensure I understand/see if I've missed anything.

The LiFePower4's spec sheet reports:
CHARGING VOLTAGE REC. 58 V
REC. BULK VOLTAGE 57 V
REC. FLOAT VOLTAGE 56.5 V
REC. ABSORB VOLTAGE 56.5 V

The Jakiper manual states:
Recommend Charge Voltage: 58.4 V

I've set the inverter/charger to:
Battery Type: L16
Battery Absorption charge voltage: 58.4 V
Battery Absorption charge time: 120 minutes
Battery float charge voltage: 56.4 V

The system runs my fridges and freezers in solar-only charging and inverter priority (failing to the mains if the battery level drop too far). Since there is a constant load on the battery, perhaps I'm going OCD and the float voltage and differences between the batteries' recommended charge voltages doesn't really matter? What would you set the charge voltage to?

Thanks,

Eric

7

Midnite DIY Series / Re: MN3548DIY battery current

« Last post by ewilhelm on January 19, 2022, 12:17:49 AM »

I typically run my system on "only solar charging" and "inverter priority mode". Today I switched it to "hybrid charging" and "mains priority mode" to fully charge a new battery. I noticed the MN3548DIY showed 20 A of battery input current, which was confirmed by the BMS and my ammeter.

Perhaps the incorrect battery current and PV current are related and only happens in "only solar charging"?

Thanks for your help.

8

Midnite DIY Series / Re: Heart broken

« Last post by dapdan on January 18, 2022, 11:27:40 AM »

Midnite,

I am interested in the 24V DIY but would like a higher PV voltage threshold. are there any plans to upgrade this or should I wait on the split phase variant to have a higher PV input voltage. Although I really need it now and not a year from now. 

9

Midnite DIY Series / Re: MN3548DIY battery current

« Last post by Wizbandit on January 18, 2022, 11:21:19 AM »

I have a 3548 and 5048 here I will test.  One thing I know from the past experiences with Charge Controllers, our Classic for sure,  is the noise on the PV wires will mess with the Hall Sensor used in DC Clamp meters and the reading will not be correct.  I will setup a shunt & Wbjr and run the DIY Inverters through it and see what readings I get...

I have contacted the SRNE Engineers to see if we can calibrate the voltage and current readings.

10

Raspberry PI / Re: Using IOTstack, Telegraph, Graphana and MQTT Classic data

« Last post by Graham on January 17, 2022, 09:01:06 AM »

I am using Grafana 8.3.0
I use whatever docker version IOTStack installs . IOTStack makes it easy to automatically  install all the needed programs like Portainer, Influxdb, Telegraph, Mosquitto, etc.
...

You can use IOTStack to generate a docker-compose.yml file to start with, then edit the file to suite your needs.
Once you have the docker-compose.yml setup the way you want it, you can use the docker commands to create and start the containers
you can also setup bash aliases https://sensorsiot.github.io/IOTstack/Docker-commands/.

If you want to pull a specific version of an image, you can specify any version that is defined in dockerHub https://hub.docker.com/r/grafana/grafana/tags?page=1&ordering=last_updated

  grafana:
    container_name: grafana
    image: grafana/grafana:7.4.3
...


note: if you run the IOTStack/build stack after you edit your docker-compose.yml file it will overwrite your edits...

Graham.