
CarpeDiem
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Everything posted by CarpeDiem
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For Auckland, 3004:2014 is available at the library. Only at Auckland Central - they won't send it to other libraries. I am waiting for them to get AS/NZS 3760:2022 on the shelf. I have been doing my test and tagging myself and there are some updates I need to get across before my tag expires. That's another great example of a standard that is not legislated but is required by a private party, there is nothing in the law requiring test and tagging, but the Marina requires it - so if I want to use my e-box - I need it test and tagged...
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Sorry IT. The citations are for the Maritime Act, specifically rule 40. Rule 40 does not apply to pleasure craft. It applies to commercial craft in survey. If you can show me a citation that applies to pleasure craft I will get off my soap box.
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OK, the voltage cutoff controller you mention is actually a pretty standard voltage cut-on controller, known as a VSR. The way you explained it that could of been an external regulator. When you start the engine, the VSR detects the alternator and joins both batteries together so that the charge goes to both the house battery and the start battery. This is not suitable for dedicated LiFePO4 as, even at 13.8v, you risk over charge. While the parallel solution would work, I recommend steering well clear of it because it's not really set and forget - and is not really beginner fri
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OK. That makes a lot more sense. I will reply to your previous message.
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Hi IT, sorry I did not explain myself clearly - my bad. You are referring to the standard - I am referring to the legislation that gives legal force to the standard. Without legislation, (or a private body**), that requires the standard be followed, the standard has no effect. Per the link you provided, AS/NZS3004:2014 is only legislated by the Maritime Act and Maritime Rule 40E - this rule does not apply to private sailing vessels. It applies to commercial sailing vessels that are in survey. The standards.govt.nz site does not list any legislation that gives force to AS/
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Can you elaborate on what this is? Part number, model?
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Depends. MOSFETs limit current so if you have one rated for 10amp it will never do more than 10amp. It's not like a piece of 10amp wire that you can push 30amps through and watch it glow red. They just won't do it. A massive inrush could destroy it. It would depend on the design of the associated circuitry...
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Your cells are designed for energy storage. They meet a different design profile. Just like some Lead AGMs are designed for starting and some are designed for deep cycle. There are LFP cells that will discharge at 180C pulse, 90C for 2 seconds and 45C continuous... A 10Ah battery made with those cells would start a 3GM30 Instead of FETs a starter battery bms would use an automotive grade relay found in electric vehicles.
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Hmm.. yeah OK, - I don't think that is the best table Back to my heat exchanger ...
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No. It says that after 7100 cycles to 70% DOD - the battery will be good for 70% of it's original capacity. So if you had a 100Ah LFP battery and you pulled 70Ah out of it every single day for 19 years then after 19 years you would have a 70Ah battery.
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BMW have had Li-ion start batteries in their production vehicles since 2014. That's about the same time that the AS/NZS standard came out saying we couldn't have Li-ion start batteries on our boats... Hmmm...
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This doesn't sound right... Can you maybe post a photo of the "aparatus"? What do you want to achieve? What's the outcome you are looking for?
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The day started with a plan to clean up some really minor corrosion on my heat exchanger, corrosion that wasn't causing any problems whatsoever and that my mechanic friend told me to "monitor" I found a suspect hx end cap - OK that's an easy fix... It has two o-rings in it. Might as well do both ends, 4 "gold-plated" o-rings from ovlov is all that's needed to fix that... Job will be over in a hour. Needed to drain the coolant, it's a year early but not a big deal might as well do it now. Performed some yoga moves getting to the petcocks. Trying to put tubes on them and twist th
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I am a strong advocate of Li-ion over LA. The Regs are stopping progress and adoption because they can't keep up with the technology. Eg, Li-ion would be perfect as a starter battery. But the regs indirectly (or maybe directly) prevent it. There's absolutely no reason what so ever for low voltage disconnect on LTO batteries. One can take them 0v at and then recharge them to full capacity. A Japanese company produces LFP cells that are designed to deliver 1200a for 10 seconds and are able to peak inrush currents of 2400a - perfect to replace a marine starter battery of 700cca
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That's an over generalization. Some AGMs made with lower grade materials may have that limit. A good marine grade AGM will be rated to accept unlimited alternator current. The current is limited by the internal characteristics of the battery. Eg, Optima Yellowtop AGMs state "no amperage limit" when charging from alternator. My 75Ah Optima D31 accepts ~65Amps when charging from empty. Many quality AGM batteries are rated at 0.5C or above by the manufacturer. But you pay for the privilege...
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1C is generally the upper limit for what's on the lfp market. Most manufacturers will tell you 0.5C recommended with fast charge at 1C. That said there's a few starting to offer 3C... but these are generally cylindrical cells. My stock Volvo Penta alternator does 115A... continually... So my design requires me to either have a minimum of 230AH of Lithium-ion or limit my alternator... But then I have exactly the same problem with Lead CARBON - if I want to do it properly... I still have to limit the alternator OR have 345AH of weight!! If I want to stay in the manufacturers recommen
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Thanks. I find it strange that 2008 is the only version referenced in the regulations. Section 3 of the Electrical Safety Regulations 2010, which is the legal instrument that gives authority to the as/nzs standard states that: the regulations do not apply to pleasure vessels unless they have connectable installations. connectable installation is one that is designed or intended for, or is capable of, connection to an external power supply that operates at a nominal voltage between 90 and 250 volts AC at standard low voltage. The above clauses in the regulations indicate
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Hey IT, I have a couple of questions, which you may be able to answer regarding the standard AS/NZS 3004.2:2014. (which is where the audio and visual alarm requirement comes from) This standard does not appear to be legislated. The latest version of the standard that is legislated in the Electricity Act is 3004.2:2008 (ref: https://www.legislation.govt.nz/regulation/public/2010/0036/latest/DLM2763782.html?search=sw_096be8ed81c5a64a_3004_25_se&p=1&sr=3) MBIE had a working document in mid 2021, one of the recommendation of which was to update the NZ electricity legislatio
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Gutted. Was hoping to get to Port Fitzroy for our first time this summer. Edit: ) Port Fitzroy Permit Exempt Anchoring Zone: means the area contained within the marine waters of Port Fitzroy, east of a line between Kotuku Point and Mt. Overlook headland of Kaikōura Island /Selwyn Island, and east of a line between the Man of War Passage and Governor Pass. Where is that?
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They are Lithium-ion. They have a Iron Phosphate cathode and a graphite anode - Li-ions move through the electrolyte from the cathode to the anode and vice versa. That's the definition of a Li-ion battery - there's a lot of misconception that LiFePO4 are not Li-ion batteries mainly cause people don't want the chemistry associated with the less safe variants. They are considerably safer than other Li-ion chemistries, but they are not the safest. This honor, (currently), goes to LTO (Lithium Titanate Oxide) - LTO isn't really suitable for boat retrofit setups because of the voltage rang
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According to the spec sheet on those batteries you can get 1000 cycles by taking them to 100% dod. As a weekend warrior, assuming one is sailing every weekend, that would be 10 years... at 100% DOD... which is very impressive, on paper... However the spec sheet does not say what the impact on DOD has on capacity. Generally using a LA battery at 50% DoD will reduce the useable capacity, so your 50% becomes smaller and smaller over time and this happens much quicker than it does for a Li-ion battery. What I have read on these doesn't say, no sulphation, rather it says that sul
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Nice setup - great to see the 2p configuration, awesome to see the insulation between the EVE cells, and great to see that you have compression! This is a smoking good DIY build! What BMS are you using? What isolator are you using? Separate charge and load busses?
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Argofet is a Victron brand name - they use MOSFETs internally, all MOSFETs, like all electronics induce a voltage drop. These units suffer between 0.03v and 0.01v drop depending on the current and the units rated capacity. If you consider that something invented in 1959 makes it old-tech then I guess that they are old-tech - but you will find them in the power supply of pretty much every modern day piece of electronics...
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I didn't watch the video. The principle is relatively straight forward but requires an understanding of charge discharge profiles... 1. Lead acid rests at ~12.8v and floats at ~13.2v 2. LFP rests at 13.32v (there is no float for lfp) So when in parallel, without any load, the LFP is float charging the LA. As the load comes on the LFP will provide the power to the load. Once the lfp goes below the LA float voltage, power will be taken from the LA, but the amount of energy between 12.8v and 13.2v is insignificant and just surface charge. So the lfp will still provide
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There's nothing unsafe with doing this (unless your BMS karks it). There's a few gotchas: You need a programable BMS that will switch off the Lithium-ion battery or it will overcharge... Usually one would program it for 3.55v/cell but you could be more conservative. This means that you won't get full capacity. Because you are switching off at 3.55v, never getting into the CV phase of the charge cycle and not immediately putting load on the battery, you will create a memory effect in the Li and the addional capacity will eventually be locked out. Once you start taking