BMS choices -- contactor based

[sailingharry]

I'm trying to settle on a BMS. My power needs are fairly high, potentially over 300A both charge and discharge. Also, since it is going on a boat, I have to be aware of ABYC (building code for boats) requirements. Also, since it's on a boat, I have space and power constraints. So, that said, I need:
* Contactor based (I'm going to use a single contactor)
* Multiple I/O ports -- one to open main contactor, one to set a HV alarm, one to turn off charging sources, one to turn off discharging sources and alarm, one to open main contactor. Depending on configuration, this can be done with 4 ports.
* Balancing. I'm looking at 600-900Ah, can this be done with passive? I don't know how much balancing is actually done on an active battery, or does it tend to stay close.
* Display. I have and will keep an old LINK 2000 battery monitor, which will show me SOC, pack volts, and amps. This may be all I need on a daily basis, in which case a phone-based solution for details is fine. Some BMS use a web browser to get to the controls, which seems very complex for quick checks.

Assessing the market is not easy! But I've found
* 123Smart, Chargery, and JK don't seem to have more controls than one or two main contactors. No alarms, no charge/discharge controls. So all fail.
* Nuvation at $764 is nice, but way higher cost than anyone else. Also, no display at all.
* Orion 2JR at $670 is also likely to meet the requirements, but has no display and no wifi ($$ option).
* Batrium at $596 is a very strong contender. I can't really work out all the details on making it work, but it looks like it has everything. It can't use my existing shunt, which is unfortunate. It has no display at all, but has a wifi connection for using a phone browser.
* REC ABMS at $572 (with optional wifi module) is a very strong contender as well. I've worked through most of the details and I think it can do it all. I think it is the only Active ballancer, at 2A. I'm very confused at the two firmware options -- CAN and non-CAN. Even though there are 4 ports, I don't think they can be configured to meet my plan. But I think it is "close enough." There is no display. Cell control is through phone browser. The physical device is very robust.
* Electrodacus at $162 (am I reading that right?!!) It has the same control limitations as the REC (ie, I can't get a HV alarm), but still "close enough." Passive balancing (is that enough?) It actually has a display. It requires a high side shunt, so I'll end up with 2 shunts on the system (my LINK on the low side).

So, questions:
* The bang-for-buck for Electrodacus seems hard to resist.
* The lack of display for everyone else is a problem. Especially since there are no "apps." The Victron App, for instance, is "open and read data." These all seem to be "connect to wifi, open browser, navigate to URL, read data."
* Am I correct that my LINK giving me SOC, volts, and amps gives me 99% of all I need on a daily basis, and I don't actually need to look at the BMS controls?
* Is the Electrodacus passive balancing enough?
* Did I miss a worthy contender in my list?
* Am I being foolishly attracted to the low price of the Electrodacus, and the extra $400 for a REc or Batriumis money well spent?

Thanks for input!

 

[OliveJuice]

Following

 

[grizzzman]

I'm trying to settle on a BMS. My power needs are fairly high, potentially over 300A both charge and discharge. Also, since it is going on a boat, I have to be aware of ABYC (building code for boats) requirements. Also, since it's on a boat, I have space and power constraints. So, that said, I need:
* Contactor based (I'm going to use a single contactor)
* Multiple I/O ports -- one to open main contactor, one to set a HV alarm, one to turn off charging sources, one to turn off discharging sources and alarm, one to open main contactor. Depending on configuration, this can be done with 4 ports.
* Balancing. I'm looking at 600-900Ah, can this be done with passive? I don't know how much balancing is actually done on an active battery, or does it tend to stay close.
* Display. I have and will keep an old LINK 2000 battery monitor, which will show me SOC, pack volts, and amps. This may be all I need on a daily basis, in which case a phone-based solution for details is fine. Some BMS use a web browser to get to the controls, which seems very complex for quick checks.

Assessing the market is not easy! But I've found
* 123Smart, Chargery, and JK don't seem to have more controls than one or two main contactors. No alarms, no charge/discharge controls. So all fail.
* Nuvation at $764 is nice, but way higher cost than anyone else. Also, no display at all.
* Orion 2JR at $670 is also likely to meet the requirements, but has no display and no wifi ($$ option).
* Batrium at $596 is a very strong contender. I can't really work out all the details on making it work, but it looks like it has everything. It can't use my existing shunt, which is unfortunate. It has no display at all, but has a wifi connection for using a phone browser.
* REC ABMS at $572 (with optional wifi module) is a very strong contender as well. I've worked through most of the details and I think it can do it all. I think it is the only Active ballancer, at 2A. I'm very confused at the two firmware options -- CAN and non-CAN. Even though there are 4 ports, I don't think they can be configured to meet my plan. But I think it is "close enough." There is no display. Cell control is through phone browser. The physical device is very robust.
* Electrodacus at $162 (am I reading that right?!!) It has the same control limitations as the REC (ie, I can't get a HV alarm), but still "close enough." Passive balancing (is that enough?) It actually has a display. It requires a high side shunt, so I'll end up with 2 shunts on the system (my LINK on the low side).

So, questions:
* The bang-for-buck for Electrodacus seems hard to resist.
* The lack of display for everyone else is a problem. Especially since there are no "apps." The Victron App, for instance, is "open and read data." These all seem to be "connect to wifi, open browser, navigate to URL, read data."
* Am I correct that my LINK giving me SOC, volts, and amps gives me 99% of all I need on a daily basis, and I don't actually need to look at the BMS controls?
* Is the Electrodacus passive balancing enough?
* Did I miss a worthy contender in my list?
* Am I being foolishly attracted to the low price of the Electrodacus, and the extra $400 for a REc or Batriumis money well spent?

Thanks for input!

The ElectroDacus was my 3rd BMS ( Chargery was number 2 and I would not recommend ) It has been going for years now. As for balancing it depends on how matched your cells are. The display is handy for set up and troubleshooting but I agree the link 2000 would be fine for day to day info plus if you opt the wifi module you can see basic info that way..

 

[toms]

Look at the TAO BMS. Made specifically for marine applications. Only potential downside is it’s a small operation so less chance of long term support.

REC can trigger a HV alarm as this can be in conjunction with the cell / pack HVD.

 

[Ampster]

Orion 2JR at $670 is also likely to meet the requirements, but has no display and no wifi ($$ option

I use an Orion Jr BMS on my 42kWh pack. The balancing current is not enough for my Grade B EVE LF 280 cells so I turned off the balancing and installed a 2 Amp active balancer.
Wifi is available with a separate device sold by Orion and it has nice graphs.

 

[gdjenkins]

I use an Orion Jr BMS on my 42kWh pack. The balancing current is not enough for my Grade B EVE LF 280 cells so I turned off the balancing and installed a 2 Amp active balancer.
Wifi is available with a separate device sold by Orion and it has nice graphs.

what contactor do you use? im considering purchasing same orion bms but have 0 knowledge about it and i thought you is only for 16cells? are you just monitoring groups then? many thanks in advance
gerard

 

[Ampster]

what contactor do you use? im considering purchasing same orion bms but have 0 knowledge about it and i thought you is only for 16cells?

I used a Kilovac contactor. The Orion JR is 16 cells or less, but Orion makes BMSs for many more than 26 cells in series since their heritage is EVs which often ha higher voltage packs.what is your application that you would be going higher voltage than nominally 48 volts? My pack was 48 cells but 3P16S so each of the three parallel groups were monitored as one cell. Otherwise if you did 16S3P you would need three BMSs and have essentially three 48 volt packs.

 

[BentleyJ]

You want a contactor that has low standby current, called "Economizer" coils. However, that is still a 24/7 parasitic load. I solved the problem with a magnetic latching contactor but that required a custom PCB that will generate the necessary current pulse to open the contactor when the BMS relay opens.

 

[Ampster]

You want a contactor that has low standby current, called "Economizer" coils. ....

Yes, there are models of the Kilovac and others with "Economizer coils".

 

[OffGridInTheCity]

In my setup, the BMS (Batrium) triggers the coil of an external shunt-trip because.... the 300a+ level is beyond anything you'll find integrated into a standard BMS like Daly. Mine is a ABB SACE S3 400a w/24v coil. This allows you to choose a cheaper BMS as long as it has external relay capability.

I went with a used ABB SACE from ebay. Here's an example - https://www.ebay.com/itm/285531798960 ABB SACE is a top level product for the 300a+ level - e.g. they are big and heavy because 300a-400a DC arcing is a 'big deal' for a reliable shunt-trip. They seem to be prevalent on ebay and the listings change month to month, so patience can often find you the right amps, coil and for better than $300 in the example above.

I also have a Gigivac relay I use with a Chargery BMS. Gigivac makes a wide range of relays (as apposed to shunt-trip) in the 300a+ range with a range of coil voltages and optimization for low power to maintain closed relay state. Here's just one quick example of $130 500a - https://www.ebay.com/itm/156158597140 Gigavac has good documentation to show the model numbers for a complete range of options to find something specific for you're BMS/situation - https://www.tti.com/content/dam/tti...-open-contactors-datasheet-specifications.pdf And they seem to be pretty easily available to order.

 

[hwy17]

There is also the choice with an Orion about whether to run it off 48v pack power, or another power source. In DIY solar, most people run it on pack power, in DIY EV, most people use a 12v auxiliary battery. I use a 12v aux for my DIY solar build.

This is relevant when choosing the contactor, because the contactors come in different coil voltages.