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

[Federico993]

Thanks for the answer, the fact is that I am not so familiar with relays and opto couplers darlinghton relays.

You mean, it would be better to send a stop charge signal to the Alternator Regulator (Ignition) using a Opto Coupler relay since BMS can do this checking each cell of the House bank, instead of checking the SOC of the BMV?

I mean, the BMS could decide to open the charge bus though the SOC isn't 100%, due to a faulty cell.

What would be the threshold of the Opto Coupler for the Alternator Regulator?

For example, you stop charging the House Bank with the Cristec and the Alternators at 80% of SOC, leaving the Solar power feeding the House bank to the 100%.
But in my case scenario I'll charge the House bank entirely with the Alternator, the external Regulator will put the Alternator in Floating mode it self and will stop feeding the House bank after the set time.
-> So, the threshold for the Alternator Regulator in my system should be upper the Bulk voltage, but under the UVP Relay (Charge Bus) threshold.

This way the Threshold of the Opto Coupler can't be the same as the Multiplus one.

I am a little bit confused today

[Federico993]

Ok, I can use the Inverter (Multiplus/Quattro) threshold (3,65V) on the BMS to send a stop charge signal to the Alternator Regulator.
It means that the Bulk voltage of the regulator needs to be set at 14-14,2V MAX.
If cells are balanced, 14,2V means 3,55V on each cell. It is the max voltage expected to see during the Alternator charging, but if the cells somehow reach the 3,65V, the BMS will send the stop charging signal to a relay that will turn the Alternator Regulator to Off (Ignition).
This will happen a little bit earlier than the LVP occurs (3,75V).

I am aware that these thresholds are really near among them, so I think it would be better to use 3,50V (14,0V) or 3,52V (14,1V) for the Bulk Voltage of the Alternator Regulator.
The minimum voltage for the Cells Balancing would be set at 3,42V according to the settings who CNB is using.

This way the Alternator would charge with a Bulk Voltage of 14,0V-14,1V and the Inverter/Charger (Multiplus/Quattro) would have a maximum Bulk Voltage of 3,65V, then it would switch to Float Voltage.

CNB, do you think it would work without issues? I mean mostly for Cells balancing.

What kind of relay would be better to use to disconnect the ignition wire of the Alternator Regulator? Bi-Stable, Solid state FET?

[s/v Jedi]

Originally Posted by Federico993

Ok, I can use the Inverter (Multiplus/Quattro) threshold (3,65V) on the BMS to send a stop charge signal to the Alternator Regulator.
It means that the Bulk voltage of the regulator needs to be set at 14-14,2V MAX.
If cells are balanced, 14,2V means 3,55V on each cell. It is the max voltage expected to see during the Alternator charging, but if the cells somehow reach the 3,65V, the BMS will send the stop charging signal to a relay that will turn the Alternator Regulator to Off (Ignition).
This will happen a little bit earlier than the LVP occurs (3,75V).

I am aware that these thresholds are really near among them, so I think it would be better to use 3,50V (14,0V) or 3,52V (14,1V) for the Bulk Voltage of the Alternator Regulator.
The minimum voltage for the Cells Balancing would be set at 3,42V according to the settings who CNB is using.

This way the Alternator would charge with a Bulk Voltage of 14,0V-14,1V and the Inverter/Charger (Multiplus/Quattro) would have a maximum Bulk Voltage of 3,65V, then it would switch to Float Voltage.

CNB, do you think it would work without issues? I mean mostly for Cells balancing.

What kind of relay would be better to use to disconnect the ignition wire of the Alternator Regulator? Bi-Stable, Solid state FET?

I think that setting the alternator at 14.2 or even 14.0 leads to overcharge during extended use of the engine. I don’t think using the BMS to shutdown the alternator is the right way either because that is meant to be a last resort protection mechanism. CNB using the relay in his battery monitor to set a SOC at which to stop charging is much more suitable

[Federico993]

Originally Posted by s/v Jedi

I think that setting the alternator at 14.2 or even 14.0 leads to overcharge during extended use of the engine. I don’t think using the BMS to shutdown the alternator is the right way either because that is meant to be a last resort protection mechanism. CNB using the relay in his battery monitor to set a SOC at which to stop charging is much more suitable

The Bulk voltage of the Alternator would be 13,9-14,0V, then it would switch to Absorption Voltage which has a lower voltage and after this, the regulator would switch to a Float Voltage which needs to be under 13,6V. Float voltage will be 13,5V.
The Opto Coupler relay on the REC BMS will turn the Alternator regulator Off only if the BMS reads >3,6-3,65V on a single cell to prevent an Overcharge attempt.
This is just the first level of protection from Charging sources. If the overcharge process continues, the OVP relay (set to 3,75V) will disconnect the Charge Bus-bar, opening the circuit.

From MarineHowTo:

WARNING LEVELS:

HVC = High Voltage Warning or Cut: This warns of or stops an HVE or High Voltage Event.

HVC is a cutoff threshold for charge sources to prevent overcharging the cells. Depending upon the BMS this can either be done at pack level or cell level. Some do this at a warning level voltage before the **** hits the fan. Generally speaking if this is a warning level event they are often pack level voltages. Remember this is a WARNING LEVEL in either audible/visual alarm or an actual cutoff of charge sources only. A well designed BMS systems for LFP cells will usually cut the charge sources at 14.2V – 14.4V depending upon brand, model etc. Some are even custom programmable.. With an HVC set to warning level the HVC occurs before a main contactor (a big high current relay) for bank protection opens. It is important to properly wire the relays for such items as an alternator as you never want to open the alternator B+/output when it is supplying a load. The proper method for breaking HVC of an alternator is to cut the power to the voltage regulator. HVC should always be monitoring CELL LEVEL VOLTAGE, and not pack level voltage, thus it can break off charging if any cell should drift out of balance and protect it from over charging.

@CNB: How do you switch the Solar Inverter off in an Overcharging situation?

[CatNewBee]

Wow, many long posts to swallow.

Let me first sort some terms out.

An Alternator is a one stage W-charger, it does not follow IUoU charging procedures. It simply pushes power (current * voltage) to the loads connected, it has an internal resistance (caused by the wire size and length) and is regulated by a separate field coil. It is an AC generator, the frequency is the frequency of the rpm, it is usually a 3-phase AC output. To use this in DC circuits there are Shottky diodes with low resistance and losses in a bridge circuit to rectify the output. The internal regulator operates on both temperature (overheat protection) and Voltage. If the Voltage exceeds 14.2V, the current to the field is reduced and the power /voltage drops. That's all, no fancy Bulk, Absorption, Float thing. If there is very little load, like some light bulbs, the alternator regulator lowers the field current until the output current drops and the voltage does no longer exceed steady 14.2V. Since it regulates the primary field (magnetic force), it regulates only the power output by the current, the Voltage results as P/I and is indirectly regulated. If there is no load (I=0), the voltage can become infinite or better undefined. That is the risk of frying the rectifyer diodes when running on no loads. A battery is always a steady load and prevents a run off, because it consumes immediately the voltage spike after turning off a heavy load, as a short charge current impulse.

Next thing Optocouplers. This are not relays. This are semiconductors, consisting of a LED on the input side and a Phototransistor Emitter and Collector pins on the output side, the Base is not wired, because the transistor reacts on the light of the LED. To increase the switching current, modern optocouplers have darlington transistors inside, means the phototransistor output is amplified by another transistor on the chip. Use case is galvanic isolation of circuits, so the two devices do not have any electrical connection to each other in common. There are no relay contacts.

You can directly switch a small relay with a optocoupler, but for larger relays you better use a transistor or FET as amplifier to increase the switching current. See in my circuit or in the REC manual how it can be done.

[CatNewBee]

Next topic, 14.2V and charging. in balanced LFP 14.2V are in theory 3.55V cell voltage, cells are assumed full at 3.65V, so staying infinite at 14.2V (like float) would keep the cells at 3.55V without any charging current, they will never be pushed to 3.65V and won't get fully charged. There is no danger anyway, even if you stay there for hours, because at some point you will use energy for something and the voltage will drop then causing some cycling.

If you want to prevent this, you can switch off charging. Using the BMS stop charge is a bad idea so, it reacts on cell voltage and switches when the first cell hits the value. It should be set to 3.65V - the correct setting for a full cell. Your alternator will never see this signal when running alone, because it is unable to push the battery high enough to fire up stop charge (14.2V only, it would need 14.6V) nor will your solar controller or your Quattro get this when properly configured (Absorption on 14.4...14.5V). But it will fire if the cells are out of ballance and stop charging before the BMS TAKES THE BIG HAMMER and disconnects the charge bus based on High Voltage setting (should be set to 3.75V).

You can set the stop charge signal lower, but then charging will stop erratically at various SOC, outside of the shouldes the cell voltage is almost constant, it varies a little depending on the load or charge current. Assuming all charge sources kick in, you have 300A, the cell voltage may go to 3.5V even at 50% SOC and you would stop charrging. This is not what you want.

If you really want to stop charging at a defined desired SOC, you can only do this by a programmable battery monitor, like a BMV.

[CatNewBee]

Originally Posted by Federico993

The Bulk voltage of the Alternator would be 13,9-14,0V, then it would switch to Absorption Voltage which has a lower voltage and after this, the regulator would switch to a Float Voltage which needs to be under 13,6V. Float voltage will be 13,5V.
The Opto Coupler relay on the REC BMS will turn the Alternator regulator Off only if the BMS reads >3,6-3,65V on a single cell to prevent an Overcharge attempt.
This is just the first level of protection from Charging sources. If the overcharge process continues, the OVP relay (set to 3,75V) will disconnect the Charge Bus-bar, opening the circuit.

From MarineHowTo:


@CNB: How do you switch the Solar Inverter off in an Overcharging situation?

Solar controller switches off according his own settings for Absorption and Float, if one cell goes beyond 3.750V, the charge bus would disconnect all sources. There is no Solar Inverter in my circuit, I don't use grid tied solar controllers.

Alternators dont have stages.

REC ABMS has 2 relays and 2 Optocoupler outputs, no optocoupler relays, there is no such thing.

When you run on engines you rarerly will see 14V, your fridges consume energy, your electronics, autopilot too. There is very little probability you stay extended times at such voltages and they do not harm your LFP. But if you want to stop charging and disconnect the alternator, you can do so by using your battery monitor based on SOC.

[Federico993]

Originally Posted by CatNewBee

Wow, many long posts to swallow.

Let me first sort some terms out.

Wow, thanks for all the messages and the explanations!

I was talking about Bulk, Absorption and Float on the Alternator charging since these stages are well distinct on the Balmar MC614H external regulator.
Everything can be set on it, and you can feed the battery with the voltage you have choose for each step of the charging process.
It's not like with an internal regulator.

Originally Posted by CatNewBee

Next topic, 14.2V and charging. in balanced LFP 14.2V are in theory 3.55V cell voltage, cells are assumed full at 3.65V, so staying infinite at 14.2V (like float) would keep the cells at 3.55V without any charging current, they will never be pushed to 3.65V and won't get fully charged. There is no danger anyway, even if you stay there for hours, because at some point you will use energy for something and the voltage will drop then causing some cycling.

If you want to prevent this, you can switch off charging. Using the BMS stop charge is a bad idea so, it reacts on cell voltage and switches when the first cell hits the value. It should be set to 3.65V - the correct setting for a full cell. Your alternator will never see this signal when running alone, because it is unable to push the battery high enough to fire up stop charge (14.2V only, it would need 14.6V) nor will your solar controller or your Quattro get this when properly configured (Absorption on 14.4...14.5V). But it will fire if the cells are out of ballance and stop charging before the BMS TAKES THE BIG HAMMER and disconnects the charge bus based on High Voltage setting (should be set to 3.75V).

You can set the stop charge signal lower, but then charging will stop erratically at various SOC, outside of the shouldes the cell voltage is almost constant, it varies a little depending on the load or charge current. Assuming all charge sources kick in, you have 300A, the cell voltage may go to 3.5V even at 50% SOC and you would stop charrging. This is not what you want.

If you really want to stop charging at a defined desired SOC, you can only do this by a programmable battery monitor, like a BMV.
Today 21:09

I think I don't need to push the cells at 3,65V with the Alternator. That's why I'll set the Alternator regulator to 14,0V for the Balmar Bulk stage (cells at 3,5V if balanced) and I will never need to switch the regulator off since it will switch to the Balmar Float stage (a safe 13,5V as the last stage of the charging process).
The BMS will switch the Alternator regulator off only if one cell reaches 3,65V.
Doesn't matter if the Alternator will never reach this voltage, because it could occur due to a cell imbalance and the regulator will be switched to off.

- I won't set the BMS stop charging signal under 3,65V.

- Maybe I explained myself badly, but I won't switch the Alternator regulator to OFF using the BMS to prevent the issue of the prolonged "Float" voltage of the Alternator while engine is running for a long time!

I could set the BMV relay at Switching off the Alternator regulator based on SOC as well, in addition to the BMS stop charging signal which will be only for the cells safety! (first layer of protection)

For example I can Switch off the Alternator Regulator after some time (minutes, hours) that the LFP battery has reached a precise SOC and this way allowing to cycling the LFP battery bank and switching it ON after reached a lower SOC. Great in a long time engine running.

- The OVP relay will be set to 3,75V. (second layer of protection, big Hammer)

If you really want to stop charging at a defined desired SOC, you can only do this by a programmable battery monitor, like a BMV.

It wasn't my purpose, but I agree with it.

Originally Posted by CatNewBee

Solar controller switches off according his own settings for Absorption and Float, if one cell goes beyond 3.750V, the charge bus would disconnect all sources. There is no Solar Inverter in my circuit, I don't use grid tied solar controllers.

Alternators dont have stages.

REC ABMS has 2 relays and 2 Optocoupler outputs, no optocoupler relays, there is no such thing.

When you run on engines you rarerly will see 14V, your fridges consume energy, your electronics, autopilot too. There is very little probability you stay extended times at such voltages and they do not harm your LFP. But if you want to stop charging and disconnect the alternator, you can do so by using your battery monitor based on SOC.

Sorry, my fault. I meant the MPPT controller, not an inverter

I was asking this because I was wondering if a Stop charging signal needed to be sent to it too.
I know that in your system it is controlled by the charging bus set to 3,75V cell.
So I don't need any stop charging signal to send to it.

If I add a relay on the BMV to disconnect the Alternator what would be the minimun SOC that turns it ON again in a system that is actually feeded only by the alternator when you aren't connected at the grid?

I know you set it among 50% to 80% of the SOC.

Thanks again for the messages!

[CatNewBee]

Originally Posted by Federico993

Wow, thanks for all the messages and the explanations!

I was talking about Bulk, Absorption and Float on the Alternator charging since these stages are well distinct on the Balmar MC614H external regulator.
Everything can be set on it, and you can feed the battery with the voltage you have choose for each step of the charging process.
It's not like with an internal regulator.



I think I don't need to push the cells at 3,65V with the Alternator. That's why I'll set the Alternator regulator to 14,0V for the Balmar Bulk stage (cells at 3,5V if balanced) and I will never need to switch the regulator off since it will switch to the Balmar Float stage (a safe 13,5V as the last stage of the charging process).
The BMS will switch the Alternator regulator off only if one cell reaches 3,65V.
Doesn't matter if the Alternator will never reach this voltage, because it could occur due to a cell imbalance and the regulator will be switched to off.

- I won't set the BMS stop charging signal under 3,65V.

- Maybe I explained myself badly, but I won't switch the Alternator regulator to OFF using the BMS to prevent the issue of the prolonged "Float" voltage of the Alternator while engine is running for a long time!

I could set the BMV relay at Switching off the Alternator regulator based on SOC as well, in addition to the BMS stop charging signal which will be only for the cells safety! (first layer of protection)

For example I can Switch off the Alternator Regulator after some time (minutes, hours) that the LFP battery has reached a precise SOC and this way allowing to cycling the LFP battery bank and switching it ON after reached a lower SOC. Great in a long time engine running. [emoji2]

- The OVP relay will be set to 3,75V. (second layer of protection, big Hammer)



It wasn't my purpose, but I agree with it.




Sorry, my fault. I meant the MPPT controller, not an inverter [emoji3]

I was asking this because I was wondering if a Stop charging signal needed to be sent to it too.
I know that in your system it is controlled by the charging bus set to 3,75V cell.
So I don't need any stop charging signal to send to it.

If I add a relay on the BMV to disconnect the Alternator what would be the minimun SOC that turns it ON again in a system that is actually feeded only by the alternator when you aren't connected at the grid?

I know you set it among 50% to 80% of the SOC. [emoji2]

Thanks again for the messages!

If you use an alt with a programmable external regulator, you can set it up like any other charge source, no need for different settings.

Regarding solar controllers, you can control them in different ways. It is up to you what way you chose.

1st and obvious by settings for Absorption Voltage, temp compensation and float Voltage.

2nd by data integration and remote commands (CAN, VEDirect)

3rd by using remote switch contacts on the controller and a relay.

4th by using a relay, that disconnects the solar panels

5th by disconnecting the charge bus to battery. not all may survive this, so be careful.

[CatNewBee]

http://nauticmag.com/2020/12/07/elec...jimmy-cornell/

good read for some e-propulsion proponents, when reality hits dreams.

[CaptainRivet]

Why is not every centimeter of Cornell Outremer covered in solar panels? This plus regeneration should actually cover most of there power needs...on davits 4 panels LG neon bifacial are already 2000W, I am sure you could add another 3kw of solar making it 5kw.
In this case a emergency genset would only be really needed occasionally.

[newhaul]

Originally Posted by CaptainRivet

Why is not every centimeter of Cornell Outremer covered in solar panels? This plus regeneration should actually cover most of there power needs...on davits 4 panels LG neon bifacial are already 2000W, I am sure you could add another 3kw of solar making it 5kw.
In this case a emergency genset would only be really needed occasionally.

Because its all about the regeneration system . Basically a billboard advertisement for them .

Solar or wind gen has nothing to do with it.

[aybabtme]

I'm a big fan of electric propulsion but I would never assume that regen alone would suffice to maintain a house bank while also filling up the propulsion bank, marketing claims or not. The math just doesn't add up. Having to cover the boat with solar is just the first thing I'd do,

/armchair critic

[CaptainRivet]

Well thats stupid... Every owner of a hydrogen like watt&sea could tell them that its not enough just the regeneration... It would be a perpedium mobile. Installing a genset instead multiple soalr panels on a zero emission boat/cat is mission failed...

[newhaul]

Originally Posted by aybabtme

I'm a big fan of electric propulsion but I would never assume that regen alone would suffice to maintain a house bank while also filling up the propulsion bank, marketing claims or not. The math just doesn't add up. Having to cover the boat with solar is just the first thing I'd do,

/armchair critic

For that i would go hydro before adding more solar.
https://www.wattandsea.com/en/produc...ydrogenerators
The new pod600 looks promising for cats