Magnum Energy ME-ARTR, Owner'S Manual

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2017 Sensata Technologies Page 109
Using a BMK: Setup
To view the SOC display: From the BMK Home screen, press the METER button. The 05A BMK
SOC menu appears. If the AH I/O reading is below 000 (negative number) when the SOC display
reads 99%, then increase the charge ef fi ciency setting. If the AH I/O reading is substantially
above zero when the SOC display reads 99%, then decrease the charge ef fi ciency setting.
CAUTION: The factory default charge ef fi ciency setting is Auto , which allows the
charging ef fi ciency to be automatically calculated. In most circumstances, this setting
determines the best charge ef fi ciency. If you do not know your battery’s charging
ef fi ciency, leave it at the factory default setting. If the setting is manually set but
incorrect, the state-of-charge information becomes more inaccurate with every charge.
• SETUP: 05B Battery AmpHrs Size – The Battery AmpHrs (Amp-Hours) Size represents the
amount of energy the battery can deliver. This setting is used by the battery monitor to help
calculate the battery’s SOC (State of Charge).
Default setting: 400 AmpHrs
Range: 200-2500 AmpHrs
Note: It’s important that the Battery AmpHrs Size setting is correct or else the calculations used to
determine the battery’s SOC display will be inaccurate.
Adjusting the AmpHrs Setting – From the BMK home screen (see Info in Section 9.1), press
the SETUP button. Turn the SELECT knob until the 05B Battery AmpHrs Size display appears.
Press the SELECT knob to access the Set Battery AmpHrs Size function. Turn the SELECT knob to
adjust the amp-hours setting. Press the SELECT knob to save the new setting (see Figure 9-2).
Where do I set the AmpHrs setting? Select the setting based on the 20-hour AH capacity of
your battery bank. Refer to the battery manufacturer for the 20-hour AH capacity.
How do I determine my Battery Amp-Hour capacity? The batteries should be deep-cycle
type and rated either by AHrs or reserve capacity in minutes.
• Amp-hour (AH) capacity is a measurement of how many amps a battery can deliver for
a speci fi ed length of time (usually 20 hours) until the voltage achieves 1.75 VDC/cell at
80°F/27°C.
• Reserve Capacity (RC) is a measure of how many minutes a battery can deliver a certain
amount of current (usually 25A) and maintain a voltage above 1.75 VDC/cell at 80°F/27°C. If
using the Reserve Capacity (25A), the 20-hour AH capacity can be estimated by multiplying
‘minutes reserve capacity’ by 50%.
Note: For batteries in parallel strings, add the amp-hour capacity of each string (Example: three
250AH batteries in parallel = 750 AH); for batteries in series, use the amp-hour capacity of one
battery (Example: three 250 AH batteries in series = 250 AH).
9.2 ME-BMK Operation/Monitoring (with the ME-ARTR)
This section explains how the ME-BMK (Battery Monitor kit) battery monitor works, and how to
use the ME-ARTR to obtain battery bank information. It also covers the various LCD displays that
are related to the battery monitor and the status of the sense module’s LED indicator.
Info: Battery monitor menu items are accessed via the ARTR router’s BMK Home screen.
For information on how to access the BMK Home screen refer to the Info in Section 9.1.
9.2.1 How does the ME-BMK Battery Monitor Operate?
The ME-BMK uses a precision resistor known as a shunt to measure current fl ow into and out of
the battery. The shunt provides a small voltage to the BMK sense module that is proportional
to the current fl ow. When the battery current starts fl owing, the sense module measures the
amount of current removed from and returned to the battery. The amount of current (or AHrs)
removed or returned is displayed as the METER: 05D Amp Hours In/Out value. This Amp Hours
In/Out number is compensated by the SETUP: 05A Charging Ef fi ciency value that accounts for
energy loses while charging, and is one of the factors used to determine the battery’s State Of
Charge ( SOC).