Merged LiFeYPO4 1000Ah Winston prismatic cells and all electric galley...

[CatNewBee]

Originally Posted by Federico993

Thanks again for the answer! [emoji2]

I am now looking for a raspberryPi 4 model B 4Gb, but I don't know what is the best 7" screen to use. What resolution are you actually using? And what screen do you advice to buy? Is your screen an IPS?
I can't find many hardware thread, mostly coding threads.
Have you plugged a 4G modem to the Raspberry?

No 4G modem plugged is, as you see on the pictures, but a 4G pocket MiFi router for the onboard network. 1024x600 obviously, native resolution. Cannot judge if is is the best, have not tried all the others... [emoji1787]

[Federico993]

Thank you for the tip!

What kind of RS485 to USB cable are you using?
Is it this: https://www.victronenergy.it/accesso...terface#manual?

And do you have a double SD card reader?

[CatNewBee]

For Victron the MK2 Victron VIBus to USB, for the REC, the programming cable they supply.
I have a small USB adapter for SD cards, see picture above - it turns them to an USB stick.
You can use an USB stick instead. I just recycled an old sd card as buffer memory if wlan is down for some reason. .

[BetterDays 2020]

Hello CatNewBee,

My eight Winston 700ah cells are on order with Julia at Sky Power. I have a question with regards to the terminals. I know on the 1000ah cells there are three positive and three negative terminals and on the 700ah cells there are two positive and two negative terminals. Did you connect each of these terminals together at each cell or only once at one of the outside cells where you connect to the load and charging system? I have not been able to locate any documentation on linking the cells together. I’m going to run my system in a 12V 2P4S configuration.

Thanks again,

[CatNewBee]

Originally Posted by BetterDays 2020

Hello CatNewBee,

My eight Winston 700ah cells are on order with Julia at Sky Power. I have a question with regards to the terminals. I know on the 1000ah cells there are three positive and three negative terminals and on the 700ah cells there are two positive and two negative terminals. Did you connect each of these terminals together at each cell or only once at one of the outside cells where you connect to the load and charging system? I have not been able to locate any documentation on linking the cells together. I’m going to run my system in a 12V 2P4S configuration.

Thanks again,

Only bridges to the next cell between the cells, the bus bars bridge the connectors on the edge to get a better contact / biger contact surface (negative to the shunt, positive to the fuses distribution bar). I use only 2 of the 3 poles with cell bridges and the 3rd only for the BMS sense wires for the cell voltages.

Inside the cells the poles are bridged with internal bus bars, no need to bridge them again on the other side.

[s/v Jedi]

Originally Posted by BetterDays 2020

Hello CatNewBee,

My eight Winston 700ah cells are on order with Julia at Sky Power. I have a question with regards to the terminals. I know on the 1000ah cells there are three positive and three negative terminals and on the 700ah cells there are two positive and two negative terminals. Did you connect each of these terminals together at each cell or only once at one of the outside cells where you connect to the load and charging system? I have not been able to locate any documentation on linking the cells together. I’m going to run my system in a 12V 2P4S configuration.

Thanks again,

You need to wire every terminal to meet cell specifications. So for the 700Ah cell you get 2 negative and two positive busbars. I’m getting the 400Ah cells from Julia.

[fxykty]

Originally Posted by BetterDays 2020

Hello CatNewBee,

My eight Winston 700ah cells are on order with Julia at Sky Power. I have a question with regards to the terminals. I know on the 1000ah cells there are three positive and three negative terminals and on the 700ah cells there are two positive and two negative terminals. Did you connect each of these terminals together at each cell or only once at one of the outside cells where you connect to the load and charging system? I have not been able to locate any documentation on linking the cells together. I’m going to run my system in a 12V 2P4S configuration.

Thanks again,

Interesting, I guess you are getting 8x 350Ah cells?

I have just ordered 4x 700Ah cells from Julia, preferring to have a 4S configuration and to use a single BMS (https://www.taoperf.com/main-menu/tao-bms/overview/). With 2P4S won’t you need two BMS?

[Federico993]

CNB, where have you bought your Winston cells?
What regulators are you using on the alternators?

[CatNewBee]

Originally Posted by Federico993

CNB, where have you bought your Winston cells?[emoji2]
What regulators are you using on the alternators?

GWL.eu
https://shop.gwl.eu/Winston-40Ah-200Ah/
Stock alternators with internal regulators.

[Federico993]

CNB, are you using the "venus-image-raspberrypi4-20200517094427-v2.60_22.rootfs.wic" image?
I have installed it on my rpi 4, but the screen doesn't show anything (it remains white).
The rpi 4 is working and it was configured through the LAN.
Superuser is enabled and I was following the procedure for rooting it.

The screen is connected with the HDMI cable, is your screen connected with the HDMI too?

[Federico993]

Ok, I have fixed it. Two strings were missing on the Config.txt file. Now it works like a charm

Anyway what is the real resolution that you are using on your rpi 4 CCGX?
My screen is 1024x600 resolution, but it is diplaying the CCGX software at 848x480 resolution.

[fxykty]

Originally Posted by Federico993

Ok, I have fixed it. Two strings were missing on the Config.txt file. Now it works like a charm

Anyway what is the real resolution that you are using on your rpi 4 CCGX?
My screen is 1024x600 resolution, but it is diplaying the CCGX software at 848x480 resolution.

Can you tell us the two strings?

[Federico993]

Originally Posted by fxykty

Can you tell us the two strings?

Yes, of course:

hdmi_group=2
hdmi_mode=14

[Federico993]

CNB, I am wondering if the Multiplus/Quattro Aux can be handled using only one Opto Coupler relay of the REC BMS.
Following the Victron manuals, I can see that you can choose how to set the Inverter based on the BMS that you are using.



Double contacts for High and Low cells conditions would be better (as in your scheme), but I am trying to find a way to control the Alternator regolator which should be handled by the BMS.

Feeding the Lithium Bank with the Alternator directly means that the BMS should turn the regulator off a little bit earlier than the BMS open the Charge Bus to avoid any spike.

REC BMS can do this with a custom firmware.
For example: the output relay 3 can disconnect the Alternator Regulator 4 seconds before that the BMS opens the Charge Bus via relay output 1.

But how to do this if I am already using the two Octo Coupler relays for the Inverter?

Any idea?

[CatNewBee]

Originally Posted by Federico993

CNB, I am wondering if the Multiplus/Quattro Aux can be handled using only one Opto Coupler relay of the REC BMS.
Following the Victron manuals, I can see that you can choose how to set the Inverter based on the BMS that you are using.



Double contacts for High and Low cells conditions would be better (as in your scheme), but I am trying to find a way to control the Alternator regolator which should be handled by the BMS.

Feeding the Lithium Bank with the Alternator directly means that the BMS should turn the regulator off a little bit earlier than the BMS open the Charge Bus to avoid any spike.

REC BMS can do this with a custom firmware.
For example: the output relay 3 can disconnect the Alternator Regulator 4 seconds before that the BMS opens the Charge Bus via relay output 1.

But how to do this if I am already using the two Octo Coupler relays for the Inverter?

Any idea?[emoji2]

I use the BMV charge relay. Based on SOC, better configurable.

But I don't get your point, use a Relay interface for the opto output (see my diagram) with more contacts, you can then use one to stop charge for the Quattro and another contact to stop charge from the alternator. Optocouplesr can be set to different voltages than the relay outputs, so no battery disconnect of the charge bus, just stop charge signals. You can generate as many independent galvanically isolated stop charge signals you need, there are 12V opto coupler input operated relay boards on Amazon, you can parallel as many channels you need.