View Single Post
  #18   Spotlight this post!  
Unread 26-03-2012, 20:51
fox46's Avatar
fox46 fox46 is offline
Registered User
FRC #2013 (Cybergnomes)
Team Role: Mentor
 
Join Date: Feb 2003
Rookie Year: 2000
Location: Toronto, ON, Canada
Posts: 400
fox46 has a reputation beyond reputefox46 has a reputation beyond reputefox46 has a reputation beyond reputefox46 has a reputation beyond reputefox46 has a reputation beyond reputefox46 has a reputation beyond reputefox46 has a reputation beyond reputefox46 has a reputation beyond reputefox46 has a reputation beyond reputefox46 has a reputation beyond reputefox46 has a reputation beyond repute
Re: Anyone have experince with Noco Genius chargers and FRC batteries?

Quote:
What I am thinking is that many smart chargers switch between charge and load during the charge cycle.
I've had a fair bit of experience with batteries from being involved with radio control aircraft. The majority of chargers use current sensing to determine the charge condition of conventional batteries. For a specific voltage, current approaches 0 as the cell voltage approaches the applied charge voltage. When this happens the charger switches from a "charging voltage" in the case of the accumate 5, it is 14.3V as illustrated on the graph of charge schedule on their website. Once the current drops to a predetermined rate, the charger goes into a "mantain" or trickle charge mode where it applies 13.5V. It holds this voltage unless it senses the current draw to exceed a threshold indicating the battery is accepting more charge due to a depleted state. It then switches back to charge mode applying 14.3V. This is the same method used by the KOP battery chargers which have the yellow and green light that flip flops back and forth as the battery approaches a fully charged condition. The yellow light indicates a charge cycle, the green, a maintain cycle.

Should you use more than one of these chargers on a single battery, they will each apply a charging voltage. Power will not backfeed into the charger as I understand they are equipped with a diode to prevent this. When they are both applying their 14.3V charge voltage, if the total current being drawn by the battery is greater than the 2x the threshold current which kicks the chargers into their maintain cycle, they will continue holding a 14.3V charge cycle. As this current drops and approaches 2x the threshold current, the more sensitive of the two chargers will kick into maintain mode of 13.5V. Since the other charger is still applying 14.3V it will see a jump in current which will keep it in its charge cycle. When the current drops to the threshold limit again, the second charger should kick off and both will continue in their maintain mode.



Why do you think that it is unlikely that the charge controllers on multiple banks are linked? They are all in the same housing, in the same unit.

I would think that if the manufacturer advertises that it is acceptable to bridge the banks, I would bet that the system has been designed to do this.
__________________
Mentor, Team 2013 Cybergnomes 2010 - 2014, 2016
Mentor, Team 3756 RamFerno 2011 - 2013
Mentor, Team 854 Iron Bears 2005-2007
Founding member, Team 854 Iron Bears 2000-2005

Mech.Eng.+Mgt University of Ontario 2009
B.Ed OCT Trent University 2015
Professional Education and Product Knowledge Consultant - Toyota Canada Inc.

Last edited by fox46 : 26-03-2012 at 20:55.
Reply With Quote