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Cyrix-Li-ct with lead acid house battery

Hi, Just wondering if it is possible or advisable to use the lithium version of the cyrix-ct with a SLA house battery.

Im considering this because adding a lithium house battery soon. I understand I would need to control the BMS wire of the relay to enable the relay to close.

Looks like the enable / disable voltage would work with lead acid being 13.4-13.2v


Thanks, Mike

Cyrix Battery Combinercampervanlead-acid
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3 Answers
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dazey77 answered ·

I can't see a problem with this, as long as you hold the BMS line high it should work OK.

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I am also planning to use Cyrix-Li-ct to connect 2 lead-acid batteries since my car(hybrid) charges the battery with 14.2V and Cyrix-ct seems to work with at most 13.8V. Is holding BMS line high only requirements to work Cyrix-Li-ct just like Cyrix-ct without BMS?

Yes, the plain CT has no BMS connection. A normal CT should work for you though. 14.2 is not an unusual voltage, the CT will support this just fine. Think your just reading trigger voltages. Cars can easily be over 14.2, 14.6 wouldn't be unusual.

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nzmikec answered ·

Thanks very much! I have just ordered the relay.

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nzmikec answered ·

Thanks for the answer! Do you know if the BMS line can be held at +12v (or vbatt) or is it some logic level?

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Hold the BMS at +12v/vbatt. There is also a ground connection you have to make.