I’ve just upgraded my Victron Gels to NG 200 24V batteries. My engine has an 80-amp 24V alternator which I had been running through a Sterling Power charger, which conditions the incoming current and does 2-stage charging.
The Sterling has a LiFePO4 setting, which has a slightly different charging profile from the Victron recommendation: Victron Absorption is 28.4v, the Sterling outputs 29.2; float is 27V vs 28.4v. The Sterling can’t controlled by a BMS, so is there a danger of overheating/overcharging the batteries?
I could replace the Sterling with a Victron Orion-TR DC-DC charger, but it doesn’t look like they make one that handles 80 amps - the biggest Orion-TR charger is rated 400w, which translates to about 16a at 24v. (Not sure whether the rating is for input our output current - anyone know??)
Also, I would need to connect the TR-Smart to my BMS ‘Charge Disconnect’ port, so that the BMS can shut down the charging when needed - but I also need to use the ‘Charge Disconnect’ port for my solar controller (see related post). Since the port is NH (normally high), I can’t connect both devices to it, which I could if it were normally low. Any ideas??
As @drs68 states, the new Orion XS will do 50A at 24V and importantly for you, it is fully VE Direct compatible so connected to a GX device, the BMS will manage the Orion XS charging via DVCC.
I have NG batteries and they charge rapidly at the set absorption voltage which for the NG batteries is 28.0V and float at 27.0V. I recommend that you remove the Sterling, the 29.2V is well above what is required and the lack of BMS control is a red flag should there be cell overvoltage or high or low temperature.
Thanks; does the Orion XS 50a rating apply to the input or output capacity? My alternator’s max output is 80a, though that’s prob. at higher engine revs that I would ever use…
It is 50A input and 50A output. The lower voltage side will limit the power so the other side will have lower amps at higher voltage.
50A is the highest I would like to run an 80A alternator charging lithium batteries. I run my 175A alternator at 100A in summer weather, it is OK at 120A in cooler times of the year.
Update on this: after perusing the Orion-XS manual I see that it requires connecting the house and engine battery neg. circuits, and it doesn’t provide a separate charging circuit and profile for the two batteries - which the Sterling does. Plus the 24v version of the Orion XS is 400.00.
I think I can use one of the non-LioN Sterling charging profiles below to charge the NGs while cruising, but would appreciate a reality check:
Charger type Absorb. Float
Victron NG Specs 28.4 27
Sterling LioN 29.2 28.8
Sterling AGM1 28.2 26.8
Sterling Sealed LA 28.8 27.2
Would this be a good route to go, and if so, should I very slightly undercharge for safety’s sake (AGM1) or very slightly overcharge to ensure a full charge (Sealed LA)?
Yes, I know that buying the Orion XS is still cheaper than buying new batteries - or a new boat, but if I can make the Sterling work then I’d rather go ahead and use it, at least for the short term. (I’m heading off from Amsterdam to France this morning and don’t have the time to acquire and wire in an Orion right now…)
As a reference my 600Ah of 12V NG batteries charge with 120A and a 14.0V absorption setting perfectly well, 14.0V is what the Lynx BMS runs at, but for daily absorb I run 15 minute absorb time to fit the the battery manual recommendation of 8 hrs per month.
The question is what absorption time do the batteries get from the Sterling unit, ideally you do not want to be running 2 to 3 hour absorption every day on lithium batteries even of you choose the 28.2V option.
I would go for the 28.2V setting on tj
He basis that your lithiums are more expensive and higher voltage causes them more stress. The starter battery will still get charged but take longer.
Update: I went with @pwfarnell 's recommendation and the NGs seem to be charging just fine; voltage & amperage drop down to float level once fully charged.
But long-term I would like to put in an Orion XS 1400, as the Sterling is now the only non-Victron component in my system. But it’s not clear whether the Orion actually produces 50a at 24v. I was about to order one from Dynastart but found this in their description:
Het tweede model in de XS-line-up, de Orion XS 1400, is nu beschikbaar voor pré-order. Deze batterijoplader kan worden geconfigureerd voor verschillende DC naar DC-systemen: 12V naar 12V, 12V naar 24V, 24V naar 12V en 24V naar 24V. De nominale uitgangsstroom(*) voor elke configuratie is als volgt:
12V naar 12V: 50A
12V naar 24V: 25A
24V naar 12V: 50A
24V naar 24V: 25A
If you don’t speak Dutch the important part is the last line: according to Dynastart, it only produces 25a @ 24V. This doesn’t make sense to me, as 1400w @24v = 58a, but I can’t find any info on this in the Orion datasheet or manual. Is there anyone out there using an Orion XS 1400 in a 24v system who could shed some light on how it actually performs?
Yeah, doesn’t make sense to me either. However neither the datasheet nor the manual give any details about the output at different voltages - just says max 50a. But if it’s taking in 1400w then it should theoretically be able to put out 50a at 28v - or 100a at 14v.
I emailed Dynastart and asked them where they got that info. Will let you know what they say.
