EnerSys Alpha Micro 100, Installation And Operation Manual

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017-220-J0 Rev C
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An accurate battery runtime estimation requires adjustment of the following parameter:
• Peukert Number
: Refer to "Peukert Number" on page 73 for calculation of the Peukert number to enter here.
• Battery Capacity : Rated capacity (Ah) of the battery shown on the battery data sheet at 20 hour rate. The bat-
tery data sheet shows the value for a single battery, so for a 24V system where two batteries are connected in
series, this number must be multiplied by two.
• Battery Open Circuit Voltage : This number is obtained from the battery data sheet. The battery data sheet
shows the value for a single battery, so for a 24V system where two batteries are connected in series, this num-
ber must be multiplied by two.
The Battery Runtime Remaining algorithm attempts to calculate the health of the battery to get a more accurate
prediction of the remaining battery runtime. An accurate estimate of the battery health requires that at least one
battery discharge cycle greater than 20% depth of discharge has taken place since the unit was switched on. When
the unit is powered up from an off state, the algorithm assumes that a new battery is connected to the unit. Each
discharge of greater than 20% will result in a new calculation for the relative battery health. This value is then used in
the Battery Runtime Prediction algorithm to compensate for an aging battery. We recommend that the user set up a
periodic (every 6 months) battery test with a depth of discharge of at least 20%.
UPS Maintenance > Battery:
Allows adjustments of battery string voltage, charging parameters, low battery
warning setting, periodic self test time and starts the self test.
Figure 25 — UPS Maintenance: Battery Screen