Tiger 1057

Thank you for that. I will take a look at it because strangely I was having difficulty finding a larger ah dc-dc charger

I wonder if someone could asses my thought process as I’m not the most knowledgeable. My Mastervolt Alpha Pro currently controls my alternator which charges my starter battery and house batteries AGM which are all 24v. The alpha pro is set to the AGM battery profile. If I were to install lifepo4 as the house battery this obviously has a diffent profile from the AGM. If I was to put a suitable 24 DC-DC B2B charger[s] set to a lithium profile between my starter AGM and Lithium house battery then all batteries are catered for with their different requirements. That’s still expensive but probably half the cost of the Zeus though it is less ah charging the Lithium. Have I got this right or am I talking cobblers. IF I replaced the Mastervolt Alpha Pro with the Zeus has does it manage the AGM profile starter and the Lithium house?

Guilty as charged. Apologies for the sloppy wording

Thank you for the info

Apologies as this is probably a silly question but what are you referring to as 'lifepo mode' as this is possibly the route I may take. Alternatively I am off to the States shortly and may purchase a Zeus out there and bring it back despite all the downsides of doing so:)

The way I read it going down the Hybrid route is a no no if the alternator has an external regulator. I've also read a lot of posts where people have gone down the Hybrid route and not needed to use the long wire method as everything worked as it should.

I agree but that sounds very trial and error plus as you previously mentioned it's not really an optimal solution. I suppose I'm just a wuss who's looking at all the downsides and not wanting to chance it. If it can go wrong I assure you it will go wrong for me

After reading all the replies and informative replies I'm now considering just getting a cheaper LifePo4 and managing the alternator via a temperature sensor to the controller. At least I'm protecting the alternator.

I hope it's not the case but that sounds like a recipe for disaster.

Thank you. I hadn't looked at Mastervolt batteries as I thought they were expensive but as you mentioned them I had a quick look. OMG! They are eye watering expensive. You make some really interesting points so it looks like I'm going to re-evaluate my lithium upgrade.

Thank you I will look into the 3. I’m grateful

I totally agree with regards the Alpha Pro it was just that roamer haven't tested it. My understanding was that the alternator would be protected by the ATC wire shutting the alternator down if it was getting in difficulty. Unfortunately I'm fully aware of my limited knowledge and that saying about that being a dangerous thing. This is the information that piqued my interest and led me to contact Roamer. I lifted the info from the FB 12 volt boating group. A recent update for Roamer SMART5 batteries means we now support direct alternator charging (via a regulator) AND Hybrid installs on our drop in batteries. Anyone who has looked into direct alternator charging will know that an unexpected BMS shutdown while charging can cause a voltage spike which has the potential to damage the alternator. Hybrid solves this by using a lead acid battery as a load dump that absorbs this spike - this solution is well documented on the group. If you’re using a regulator instead of hybrid however (eg Wakespeed WS500, Arco Zeus or Mastervolt AlphaPro), then up until now, you’ve been forced to buy very expensive batteries with NMEA2000 comms and an ATC signal. A regulator requires at least 2 seconds advance warning of an impending BMS shutdown via CANbus/NMEA2000 or by using a keep alive (ATC) signal wire that cuts off before BMS shuts down. This tells the regulator to reduce field to 0% and back off the charging, thereby protecting the alternator. Previously, the only batteries with ATC and/or NMEA2000 BMS warnings were super premium options such as Victron, MG Energy and Mastervolt but we’ve now got this working with Roamer drop in SMART5 batteries. The solution requires a Victron Cerbo GX and an ATC signal wire to the regulator. It works on both SMART4 and SMART5 batteries. We’ve been testing and refining this over the last 12 months using Arco Zeus regulators but it also works for Wakespeed WS500 or any other Victron integrated regulator. Roamer’s Dynamic Charge Control works by setting requested charge current to 0 and reduce the requested charge voltage BEFORE the BMS cuts off. We also use one of the Cerbo relays to provide an ATC signal that will trip if one cell is about to hit the high voltage limit. If it ever trips, this can be reset on the Cerbo screen. We’ve also got a new temperature controlled charge protocol that reduces requested charge current according to temperature and battery capacity. It’s a myth that it suddenly becomes a problem at 0 degrees, the truth is that charge current should be scaled back as temps drop. We created this so that high power alternators can safely charge our batteries - the Arco 48V alternators can chuck out up to 9000W which is potentially dangerous at low temps, even with a large battery bank. It also works for all other charge methods however as long as they’re linked to a Victron Cerbo.

That's very informative. Thank you. He may be using a 'hybrid' system and possibly using a long wire system to control the alternator heating if necessary Thank you. My whole system is mastervolt including charger,, inverter and generator. I may well go back to roamer to discuss my Alpha Pro. I realise it's an ancient unit but it would be nice if I could safely use that rather than spend £900 on something that has all the bells and whistles but which I don't fully understand.

Thanks very much for the explanation and information as it's very helpful. Thank you. Fortunately I moved to Android from Apple six months ago so that wouldn't be an issue thankfully

Thank you. Very interesting and from what you say I would have thought that Arco would have been on top of that with a solution.