The Ultimate Battery Charger
Posted: Mon Feb 06, 2017 10:10 am
The P12 Battery Charger from Blue Sea Systems may be the ultimate 120-Volt AC-operated 12-Volt-DC marine battery charger. The P12 can individually re-charge three 12-Volt batteries of similar type, providing a maximum total output current of 25-Amperes or 40-Amperes depending on model. The P12 Battery Charger has several unusual features.
The battery charging method is described as a four-stage process. The four stages of charging are called:
--bulk, when the full-output of the charger is pushing as much current as it can into the battery, until the battery reaches a state of charge of about 75 to 80-percent;
--absorption, when the charger begins to taper off its charging current, as charging continues to 100-percent;
--pre-float, a new stage unique to this charger, in which an intermediate voltage, higher than the float voltage but lower than the absorption voltage, is applied to one or two of the attached batteries while the third battery remains in the absorption stage; and,
--float, when a carefully regulated voltage is maintained to keep all three fully-charged battery at maximum charge.
The voltages during these stages are also compensated for temperature. If the battery temperature is cold the voltages for charging are increased somewhat, and if the battery is a warm the voltages are decreased. Temperature compensation of this type is typically recommended by battery manufacturers to get the best possible charging of their batteries.
In addition, the P12 charger contains four pre-set profiles for charging voltages in the four-stage process, with provisions for batteries of various constructions:
--flooded lead-acid
--gelled electrolyte lead-acid
--absorbed glass mat or starved electrolyte lead-acid, and
--thin-plate pure-lead lead-acid (see more on this below in follow up article)
If none of the pre-set profiles are suitable, the user can create his own custom charging profile to match the recommended voltages for charging a battery as provided by the battery manufacturer.
The P12 can also interface with Blue Sea Systems automatic charging relay (ACR) devices to insure that all batteries are isolated during charging. It does this by preventing any of the ACR devices from paralleling a battery with another during charging using the feature called Start Isolation in the ACR devices.
The P12 Battery Charger has a large display screen to provide status information, offer diagnostic messages, and to permit user programming of the charger operation, such as the individual charging profiles for each battery. If access to the main display is not convenient, there is an optional accessory, the P12 Battery Charger Remote, that allows for a second and somewhat simplified status display and some limited control functions to be provided at a location remote from the actual charger. A 25-foot interconnection cable is provided; cables as long as 150-feet can be used.
All these features come at a price: the P12 Battery Charger has an MSRP of $550 for the 25-Ampere model and $700 for the 40-Ampere model. It is also a rather massive device, with a housing of about 13 x 9 x 4-inches and weighing 13-lbs. The model 7520 remote display and control has an MSRP of $120.
If your boat spends lots of time at a dock and connected to shore power, the P12 Battery Charger is probably one of the best solutions for providing proper battery charging and care.
More information can be found at the Blue Sea Systems website. Visit
https://www.bluesea.com/products/category/9/58/Battery_Chargers/P12
The battery charging method is described as a four-stage process. The four stages of charging are called:
--bulk, when the full-output of the charger is pushing as much current as it can into the battery, until the battery reaches a state of charge of about 75 to 80-percent;
--absorption, when the charger begins to taper off its charging current, as charging continues to 100-percent;
--pre-float, a new stage unique to this charger, in which an intermediate voltage, higher than the float voltage but lower than the absorption voltage, is applied to one or two of the attached batteries while the third battery remains in the absorption stage; and,
--float, when a carefully regulated voltage is maintained to keep all three fully-charged battery at maximum charge.
The voltages during these stages are also compensated for temperature. If the battery temperature is cold the voltages for charging are increased somewhat, and if the battery is a warm the voltages are decreased. Temperature compensation of this type is typically recommended by battery manufacturers to get the best possible charging of their batteries.
In addition, the P12 charger contains four pre-set profiles for charging voltages in the four-stage process, with provisions for batteries of various constructions:
--flooded lead-acid
--gelled electrolyte lead-acid
--absorbed glass mat or starved electrolyte lead-acid, and
--thin-plate pure-lead lead-acid (see more on this below in follow up article)
If none of the pre-set profiles are suitable, the user can create his own custom charging profile to match the recommended voltages for charging a battery as provided by the battery manufacturer.
The P12 can also interface with Blue Sea Systems automatic charging relay (ACR) devices to insure that all batteries are isolated during charging. It does this by preventing any of the ACR devices from paralleling a battery with another during charging using the feature called Start Isolation in the ACR devices.
The P12 Battery Charger has a large display screen to provide status information, offer diagnostic messages, and to permit user programming of the charger operation, such as the individual charging profiles for each battery. If access to the main display is not convenient, there is an optional accessory, the P12 Battery Charger Remote, that allows for a second and somewhat simplified status display and some limited control functions to be provided at a location remote from the actual charger. A 25-foot interconnection cable is provided; cables as long as 150-feet can be used.
All these features come at a price: the P12 Battery Charger has an MSRP of $550 for the 25-Ampere model and $700 for the 40-Ampere model. It is also a rather massive device, with a housing of about 13 x 9 x 4-inches and weighing 13-lbs. The model 7520 remote display and control has an MSRP of $120.
If your boat spends lots of time at a dock and connected to shore power, the P12 Battery Charger is probably one of the best solutions for providing proper battery charging and care.
More information can be found at the Blue Sea Systems website. Visit
https://www.bluesea.com/products/category/9/58/Battery_Chargers/P12