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Charge Controllers and Clippers => The "KID" charge controller => Topic started by: New KID On The Block on September 22, 2014, 08:25:32 PM

Title: Float vs FloatMPPT
Post by: New KID On The Block on September 22, 2014, 08:25:32 PM
Hi There.

I'm a new owner of the KID.  ;) Mine arrived last Friday.

The main status window sometimes shows "Float" and sometimes "FloatMPPT".

What's the difference between these two states?

Thanks!

NKOTB
Title: Re: Float vs FloatMPPT
Post by: Kent3 on September 22, 2014, 08:48:31 PM
Welcome New Kid on the Block.
What FloatMPPT means is that the battery bank has reached the Float condition, however for some reason the battery has gone below the spec (voltage) you supplied for the Float condition. It could be that a device connected to the battery turned on. It's an ok condition.

Kent
Title: Re: Float vs FloatMPPT
Post by: Free Energy Freak on September 22, 2014, 09:36:32 PM
NKOTB,

Mine does the same thing during the day, if I add a heavy enough load to the batteries after it has reached "float" status.
Title: Re: Float vs FloatMPPT
Post by: tecnodave on September 23, 2014, 12:14:05 AM
I think what really is happening here is in float the controller is not in MPPT mode as little power is need at this stage, the controller, kid, Classic, and others will switch modes, in think to PWM mode......the extra power generated by MPPT mode is not needed and PWM mode is a bit less heat producing and less complex......but when solar power input falls below the needs of maintaining the float condition and or the loads increase to the point that float cannot be maintained in PWM the controller will switch back to MPPT mode which produces maybe 30 % more power than PWM mode.

My Kid's both do this as I live in the coastal fog zone and I have rapidly changing conditions.  I observe less input on my analog ampere and volt  meters and a jump in voltage when the kid does this.

This will occur on adsorb, float , and equalize cycles

This is normal behavior for this controller......just squeezing every watt out at the best efficiency.

David


Notes: PWM Mode.    Pulse width modulated......an older technology
          MPPT Mode.   Maximum power point tracking mode........state of the art conversion technology
Title: Re: Float vs FloatMPPT
Post by: New KID On The Block on September 23, 2014, 01:21:58 AM
Thanks everyone -- especially @tecnodave -- for your quick responses.

Happy Charging everyone.  ;)
Title: Re: Float vs FloatMPPT
Post by: Free Energy Freak on September 23, 2014, 03:17:38 AM
Yeah. That's it. That's what i meant, what technodave said.


:D
Title: Re: Float vs FloatMPPT
Post by: zoneblue on September 26, 2014, 08:18:55 PM
What i thought happens in float is that the microcontroller lifts the PV voltage above Vmp so as to limit the current going through the buck converter. If, later the voltage should  drop below the float setpoint the controller will drop back into Float mppt so as to try to raise the voltage back up.

The point is that Float Mppt means while  the controller  has reached float setpoint today, it is now no longer holding float, due to either loads or low insolation.