The Victron battery switch says ok for 48V systems, however specs says max voltage 48V. Will the switch be ok for a 48V battery bank with charging voltages up to 58V?
https://www.victronenergy.com/dc-distribution-systems/battery-switch-on-off
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Justin Cook for the following reason: The question is answered, right answer was accepted
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48V battery switch max voltage ?
Hi @nick5000,
The switch is designed for 48V nominal battery systems.
The operational limit is 60V.
I will get the datasheet updated to reflect that.
It will be fine "Battery Switch 275AThe Battery Switch has a continuous current rating and is suitable for batterysystems up to 48V. It has a unique ergonomic and aesthetic knob design for easyoperation."
Victron knows that a "48v battery system" is going to have more than 48v across it.
Could someone from Victron perhaps comment on this (@gazza, I'm uncertain if you're a Victron employee or not)?
Also, if it's assumed to be for 48V systems that are regularly operating at 57 or higher volts, can I please suggest an update to the documentation for the switch, to note its recommended maximum "real" voltage, not the "operating voltage of the inverter, be it 12, 24, or 48 volts?" Many switches that are similar to this one, from alternative manufacturers, say 48V and explicitly state 48V is the limit (i.e. do not regularly run the switch at 52V).
What gazza is saying is a 48 volt battery system is its nominal voltage, (i.e. in name only) just like a so called 12 volt battery system in a vehicle. The fully charged voltage at rest however in any battery is higher than the nominal voltage and while charging several volts higher than that.
Thanks, I understand the point being made - but it's still not an "official" response, right?
What I'm getting at is, if I use this switch in a 48V nominal system, but it's regularly floating between 51-57VDC, and a fire occurs - when the fire inspector comes by and asks what the switch was rated at, all I have is documentation stating 48V and I'll be out of luck (whether the switch caused the fire or not).
Sorry, I'm a worst-case-scenario kinda guy; I'd prefer if I have documentation backing me up that explicitly says "Operating Voltage Range: 0-60VDC Constant" or something.
Heat wise I’d be more concerned about the amperage going through the switch than a few extra volts.
100% agree - just maybe pushing for confirmation from Victron directly, is all. I think it's amperage that's the defining limiter, which is directly tied to overall wattage, so I'm sure they didn't intend, say, a 275A service operating at 128V or something. :)
As a side question, if I may - I'm looking at potentially doing three Quattro 10K for a three-phase 208Y/120 system, and if I do so, I would be looking at likely doing two 2/0 AWG cables for each DC terminal (two positive, two negative)... Would using six switches be ideal, here? How does Victron and their distributors prefer to handle this "dual supply" situation? I'm wondering if they'd have an issue with one of the two being turned on and having a massive surge as a result.
Obviously, if I was doing things, I would not turn on the output AC breaker I plan to install on a given phase of 208 3-phase so I would not expect loading to occur that would accidentally overload one of a two-wire setup; just wondering if there's guidance on how to turn off multiple legs of DC supply at once, or if the overall recommendation is to say something like, "Turn off ALL of the DC sources (i.e. batteries) and then service the inverters, so an individual disconnect isn't 100% required under that operational model."
@Tyler Pomerhn
That question crops up here now and again but I have never seen an authoritative response. Personally, I went the safer way of using properly sized breakers as disconnects.
Fideri
@Fideri Thanks - I do try and search on the forums before posting but didn't find an answer, and from your reply it seems it's not perfect with Victron, either.
@kevgermany thanks for relaying this to Victron, I would appreciate a best practice to use, here.
@Tyler Pomerhn True breaker prices can add up. I went with popular solar brands like Blue Sea and Outback but those were very expensive, especially when it came to high capacity breakers. I have read here people who went the cheaper route on Amazon and eBay but changed them in the end. I saw Dahools but I was suspicious of them.
Fideri
Oh and also, per the Quattro manual, the suggested Mega fuse size for the 10000kVA is 400A... but if I'm using two cables, that means the Mega for the Distributor should be 200A per line, correct? Or should it be 225 or even 250, if there's imbalance?
@Tyler Pomerhn That would be correct though there is divided opinion on whether to keep the conductors separate or join them at the fuse. It seems both options are fine, depending on what you read. Following some guidelines, I opted to combine the two positive wires at the fuse, so used a 400a fuse.
Fideri
