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SOLD Nasa Bm1 Battery Monitor

Discussion in 'General Classifieds' started by manda3000gt, Jul 7, 2015.

  1. manda3000gt

    manda3000gt Funster

    May 6, 2010
    The BM-1 is designed to monitor performance of 12 volt lead acid battery systems with capacities of up to 600 Amp hours. It is supplied complete with a precision 100 AMP shunt and a prefabricated cable assembly to enable simple DIY installation. The unit continuously monitors voltage, current (charge or discharge), number of amp/hours (charge or discharge), the batteries state of charge and the time to charge or discharge. It also monitors the voltage of the engine strat battery. This information leads to more efficient use of the battery, which can enhance battery life and reduce the risk of failure.

    Fully monitors domestic battery/bank

    Monitors voltage of engine start battery

    Supply voltage 8 - 16 Volts DC
    Supply current 1.5 milliamps
    Battery capacities 5 - 600 AMP Hour
    Load current 100 AMPS Maximum
    Charge current 100 AMPS Maximum
    Shunt Standard 50 millivolt @ 100 AMP

    Cables supplied:
    100 AMP shunt link to mate Ring terminal.
    5 Metre from display unit to battery - fused and fitted with ring terminals for shunt, fuse holder and mate ring terminal to battery.

    Display unit
    Standard 110mm square Clipper case. High contrast LCD, backlit for night viewing.
    Minimum voltage visual alarm
    Simple operation - 4 keys to select backlight, Volt/Amp/State of Charge screen,
    AMP hours or Time to run.

    How does it work?
    The minimum information required to monitor the state of

    charge of a battery is the terminal voltage and the

    charge/discharge current **. The BM1+ measures both

    these parameters and computes the state of charge

    using a complex, well proven, algorithm.

    A simple and intuitive display shows the service battery voltage,
    charge/discharge current, state of charge, and time to charge/discharge.
    The instrument also warns the user when the charge level is too low
    so that load can be shed or charging commenced to protect
    the battery. A resettable Amp Hour counter is provided for
    checking the efficiency of the charging system or keeping
    a track of power consumption and a second input lets the
    user monitor the voltage of the starter battery.
    The simple display format does not mean the internal software is unsophisticated. In fact two separate algorithms are used. One based on integrating amp hours over the charge and discharge cycle, the second based on an adaptive internal mathematical battery model.

    A unique feature of the BM1+ is its ability to use information from both algorithms, during the charge/discharge cycles, to continually update its performance. This means that, unlike many other systems that rely solely on amp hour integration, the NASA BM1+ never needs to be re-synchronised with the battery. The algorithm includes Peukert's equation to ensure accuracy over a wide range of load currents.
    The BM1+ does all this whist consuming a meagre one and a half milliamps. It is a true battery monitor, easy to install and excellent value for money.

    ** Some say that they can calculate the state of charge from the terminal voltage only but, as we all know, the terminal voltage falls when the battery is under load and rises when under charge. This fall and rise can be quite substantial, especially when a heavy current is flowing, so how can the terminal voltage be used to calculate anything without knowledge of the magnitude of the current involved?

    £70 in original box with new wiring loom

    I will be at the Saltfleet meet or could get it to the Malvern Show
  2. Taran_Las

    Taran_Las Funster

    Mar 26, 2009
    Yr Wyddgrug
    I'd like it if you would be willing to post it?



    PM sent too.
    Last edited: Jul 7, 2015
  3. manda3000gt

    manda3000gt Funster

    May 6, 2010
    PM sent
    • Like it Like it x 1

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