Solar Stik 21-0202317, Operator And Maintenance Manual

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Operator and Maintenance Manual for the 24VDC Li ESM 2000
April 2022 | Solar Stik® Inc. 28 |
If charging at any temperature lower than 68 ºF (20 ºC), use a charger with a current capability
>25 A. The internal battery may need to heat to charge optimally (power to heat takes precedent over
charging). The internal heater alone requires 20-25 A to operate. To charge and heat simultaneously,
the charger must supply >25 A. If the charging source provides less than 25 A, the battery will use
its stored energy to heat itself. This will drain the battery instead of charging. This situation will be
apparent if the Battery Status Indicator reports a negative current value during charging and when
there is no other load connected to the ESM.
1. Connect a constant voltage charging source to the ESM 2000 with the voltage set between 27.5
and 30.5. A voltage of at least 29.5 is needed to charge to 100% SOC.
NOTE
– if the ESM battery was previously
over-discharged
, it will need to be connected to the
charge source for at least 2 minutes, or power-cycled (toggling POWER switch ON>OFF>ON)
before charge current will begin to flow
2. Enable the charging source and allow the ESM 2000 to charge. Remember, the battery may heat
itself before charging if the ESM internal battery is colder than 68 ºF (20 ºC).
3. The ESM 2000 should continue to charge, balance, and taper until it reaches the voltage setpoint
at less than 0.5 A. At this point the ESM 2000 can be considered to be fully charged.
Maintenance Charging
The 24VDC ESM 2000 has a high current capacity. For this reason, a constant voltage-type
maintenance charger should be used with the voltage fixed at the optimum charging voltage (29.5 –
30.5 VDC) for the ESM 2000. Any non-Solar Stik charger will need a custom cable to connect to the
Power port of the ESM 2000.
A Solar Stik PRO-Verter 5000 or HyPR 6000 are ideal maintenance chargers. Both are programmable
battery chargers with the capacity to charge one, or bank of ESM 2000s. Furthermore, these Solar
Stik charging components are easily connected to ESM 2000s using Inter-Connect cables and Inter-
Connect Strips.
Internal cell balancing
Over time a voltage difference may accumulate between the eight (8) super cells of the ESM internal
battery, resulting in an apparent capacity loss. To re-balance the ESM internal cells, charge the ESM
between 27.5 and 30.5 V until the maximum difference between cells is 5 mV or less. Individual cell
voltages can be read over the CAN Bus Data port (Contact Solar Stik Technical Support for more
information).
If connection to the CAN Bus Data port is not an immediate option, leaving the ESMs in charging
mode for an additional 24 hours after they have reached 100% SOC will balance the internal battery
super cells. The Battery Status Indicator may provide a range of values for SOC. If so, another
indicator of a full charge is when the voltage reported by the ESMs is at the charging voltage set
point and the current value is < 0.5 A.