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Recommended Procedure to attach "DALY SMART BMS" to "4S" batteries.

There are several different models of Daly Smart BMS. This is with reference to a 4S BMS board with black heatsinks and no fan.
  1. Before adding Bus Bars, verify that Voltage on each cell is identical.
  2. Add Bus Bars, and wire the individual balance wires from the unconnected balance wire header to the battery lugs (being sure of the order of connections). DO NOT have the balancing plug connected into the BMS while connecting these wires.
  3. Connect the "B-" wire to the batty pack grounding lug ("-" terminal on the first cell).
Only now plug the header for the five BMS leads into the Daly BMS.

In larger Daly BMS units ("8S" and etc.) you can now check for zero resistance between "B-" and "P-", but with small 4S models it will be infinity - the BMS is not yet active. It can be activated in either of two ways.

  1. plug the UART-USB cable into a computer; or
  2. #2, start charging between your "P-" lead and the (fused) "12v" lug of your battery pack.
My thanks to member HighTechLab for providing corrections to a previous and erroneous earlier version.
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This procedure alone will not work every time, in fact most of the time it will not work. I sell/distribute BMS units, and have provided countless customers with technical support and instructions.

Daly has TWO different styles of Smart BMS.

The 3s, 4s and 5s units are DIFFERENT than larger units.

3s, 4s and 5s units WILL NOT activate with just this procedure - you have to either apply charge current to P- OR plug the UART-USB cable into a computer.

Larger BMS units also have a "KEY" port on the side, it also can be used to wake up the BMS units.
Hopefully this helps others as this is what i found while having issues getting mine to work and worked out this method