Output-Disabled Region; Brownout Voltage; Ksi And B+ Input; Battery Discharge Indicator - Kohler Curtis F Series Manual

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Output-Disabled Region

This is a limited operation region. The output may be disabled and other functions may be disabled.
Motor operation is disabled. Displays may turn off and input devices stop working.
• After 5ms controller bridge is disabled, motor current shut off.
• After 64ms, CAN, external supplies and VCL execution is disabled, and the controller will

Brownout Voltage

The F-Series controller model determines the brownout voltage. It is fixed and not changeable.
When the controller's keyswitch voltage falls into the brownout voltage region (33% > brownout
≥ 0V), the controller bridge is switched off (i.e., motor current is stopped). Functions such as the
inputs, communications, and the external power supplies may also be disabled or go out-of-range.
Once in the brownout region, the controller will react accordingly should the brownout-voltage
condition recover:
• After 5ms controller bridge is disabled, motor current shut off.
• After 64ms, CAN, external supplies and VCL execution is disabled, and the controller will
The 24V F2-A may brown out sooner based upon loads.

KSI and B+ Input

Note that KSI (pin 1) and the B+ terminal (when the main contactor is closed) are at battery voltage.
The controller's capacitor-bank pre-charge is via KSI, as the pre-charge function is performed prior
to the main contactor's closure. An incorrect battery or parameter settings can trigger the various
under- and over-voltage faults and controller responses.

BATTERY DISCHARGE INDICATOR

The lead-acid battery discharge indicator (BDI) algorithm continuously calculates the battery state-
of-charge (SOC) from the keyswitch voltage (KSI, pin 1). The result of the BDI algorithm is the
variable BDI that is the state-of-charge percentage. The BDI variable is viewable in the Programmer
app's System Monitor » Battery menu. When the controller is powered-down (KSI off), the present
BDI percentage is stored in nonvolatile memory.
For flooded lead-acid batteries and sealed maintenance-free lead-acid batteries, the standard values
for volts per cell are as follows.
Use these standard values for the battery's starting point in setting the Reset, Full, and Empty Volts
Per Cell parameters (see the Programmer app, Application Setup » Battery Setup » BDI Setup menu).
Note: For non-lead-acid batteries, including Lithium-Ion battery packs, use the battery pack's
or cell manufacturer's approved Battery Management System (BMS) for determining the SOC.
3 — APPLICATION-SPECIFIC FEATURES
reset when voltage recovers.
reset when voltage recovers.
Reset Volts Per Cell
Full Volts Per Cell
Empty Volts Per Cell
Curtis AC F2-A, F4-A, F6-A Motor Controllers – FOS 4.5 – April 2022
Lead-Acid Battery Type
Flooded
2.09
2.04
1.73
Sealed
2.09
2.04
1.90
pg. 35