Quick follow up on battery protect boards

Anton asked this morning if those little boards are at risk from overcooking. Each one is rated to handle just under 2 amps. We doubled them up on each cell, figuring about 3.5 amps working capacity. The 400 watt solar array, converting through the Victron MPPT controller, is pumping at maximum about 6 amps total to the batteries. So with 4×3.5=14 amps of resistance capacity, I think we’ll be fine. Jeff said that in practice on his big cat in the tropics, yes the boards got warm when they kicked in, but never hot. We mounted them with double sided tape, which gives an air cushion under most of each board, and the whole cabinet is a good heat dissipation sink. Hopefully we’ve solved for Anton’s warnings.

Locals, let me know if you want to sail the boat next week. Throw some dates out and we’ll make some plans.

7 thoughts on “Quick follow up on battery protect boards

  1. Alas, as the batteries are in series, each resistor board will see the full amperage. But if your voltage cutoffs are tight, it should be fine. Resistors of course are “sliding scale”; more voltage means more current and vise versa. So at3.6 they will suck less amps than at 3.7 etc.


  2. Re Sailing during next week …. Other than Wed, would be interested in any sails outside ….. weather accepting. Rick H

    Sent from Mail for Windows 10


  3. If you haven’t already, you should wash off any solder flux residue with alcohol or DI water and then give the boards a coat of conformal coat spray (techcoat or similar). This will help protect from accidental shorting and from condensation and eventual corrosion.


Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s