Yacht Devices NMEA 2000 YDBM-01, Руководство пользователя

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III. Understanding the Basics
The primary use of the Device is to monitor battery voltage, current, temperature (via an external
temperature sensor) and a number of calculated parameters, such as state of charge and consumed ampere-
hours, via MFDs, instrument displays, PCs or mobile gadgets connected to an NMEA 2000 network.
The Device has three input wires which may be connected to a marine battery or other DC source
(see Figure 1 in Section I) using an appropriate external shunt (purchased separately). The Device
is capable of measuring both current and voltage. Both positive and negative amperage is measured.
Negative values indicate battery discharge, positive indicate charging.
To report battery status and perform more accurate calculations, the Device requires battery temperature
provided by an external NMEA 2000 thermometer, for example, Yacht Devices' Digital Thermometer
YDTC-13.
Calculations of state of charge (SoC), consumed ampere-hours, time remaining and state of health
(SoH) are based on Lead Acid or Lithium-ion batteries. Further information will primarily relate
to these battery types. NiCad and NiMH batteries have significant memory and self-discharge effects,
etc. which are not taken into account in calculations. Use of NiCad and NiMH batteries with the Device
will decrease the accuracy of the calculations. Calculations can be turned off (see CALCS parameter
or YD:CALCS command in Section IX), and the Device may be used to monitor battery voltage, current
and temperature (with an external temperature sensor).
To obtain results for SoC, consumed ampere-hours, time remaining, SoH calculations usable, you have
to specify the battery’s characteristics, such as nominal voltage and capacity, in Device settings.
If the capacity value is rated for a discharge rate other than 20 hours, you must specify the latter
as the NOMINAL_RATE parameter value (see Section IX).
Since the Device is powered from the NMEA 2000 network, the Battery Monitor must be permanently
connected to both the network and the monitored battery/DC source. This is a proven way to obtain
credible values of state of charge, consumed ampere-hours and time remaining. Otherwise, you can rely
only on voltage, current and temperature readings.