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arran-pritchard asked

Orion-Tr Smart DC-DC Charger Isolated 24/24-17 (400W) - connection guide

Due to the issue of burning out the alternator or blowing it up when the BMS disconencts the LiFePo4 battery, I have purchased these DC-DC chargers to charge LiFePo4 batteries from the alternator on my boat.


In the manual the charging setup shows the following as the connection diagram.

screenshot-2022-07-30-142943.png


My alternators do not have a "starter battery" as they are intended soley for charging the house battery bank which is a 24V ( as opposed to the starter batteries which are 12V and are charged by te 12V alternators )

Therefore is the following connection ok ? i.e. ommitting the "starter battery" from the configuration ? Does the DC-DC charger use the starter battery as a energy dump when / if the BMS disconencts the LiFePo4 battery ?

untitled.png

Thank you your response.

Regards

Arran.

orion-tr smart
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4 Answers
Mike Dorsett avatar image
Mike Dorsett answered ·

omitting the 'starter battery' will again leave your alternator exposed to over voltage on the output if the BMS or the orion turns off. This depends to an extent on the alternator regulator and rectifier pack. I have seen some "Dummy Battery" devices that are designed to protect alternator regulators in this type of setup, probably consisting of a big 15V zenner and a capacitor. If you consider improving your alternator then a smart alternator regulator may allow a remote shutdown or lower "float" voltage to be generated. The problem with using an external step up to 24V is that this removes the battery voltage reference from the alternator.

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arran-pritchard avatar image
arran-pritchard answered ·

I feel that I may need some technical support / guidance through this setup.


My boat has two alternators, a 12V alternator for charging the 12V starter battery and a 24V alternator for charging the battery bank, neither alternators are "smart" alternators as they were both connected to lead acid / gel batteries.


There is no starter battery on the 24V alternator as it is soley used to charge the house battery bank which was lead acid / gel but has recently been replaced with a LiFePo4 battery bank with BMS.


I understand that the 24V alternator needs protection from the LiFePo4 battery bank, so I have purchased these Orion Isolated DC - DC Chargers thinking that these will provide the required protection for the 24V alternator.


May I get some assistance on what more step(s) I need to take to protect the 24V alternator.


Thank you.

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arran-pritchard avatar image
arran-pritchard answered ·

is all that is required is to place a small 24V lead acid / gel battery on the alternator side of the Orion charger ?

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kevgermany avatar image kevgermany ♦♦ commented ·
That would do it.
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arran-pritchard avatar image
arran-pritchard answered ·

I think I may have found the answer...

Sterling Power - ALTERNATOR PROTECTION DEVICE

https://sterling-power.com/products/alternator-open-circuit-protection-device

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