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Quick Start Guide Stabiliti™ Series PCS
MAN-00114, Rev D
Watchdog Timer
IPWR recommends that our watchdog timer function be utilized in all production Converters
deployed by your Company. This ensures that if a system controller fault occurs, or a
communications failure occurs between your system controller and the Converter, the system
will idle itself after watchdog countdown. After a user writes an update to the watchdog timer
register, the timer will count down and upon reaching zero the Converter will be automatically
set to an idle state. The Converter is shipped with the watchdog feature disabled.
SECTION 6.0 CONTROL METHODS
Via the Modbus RTU or Modbus TCP interface, there are numerous and flexible means to
transfer power amoung Converter power ports. These port-specific operating modes are
collectively known as “Control Methods” and include MPPT, GRID POWER (GPWR), FACILITY
POWER (FPWR), DC Power (PWR), DC CURRENT (DCA), NET, and IDLE. There is a
dedicated Control Method register for each port of your PCS.
Each Control Method may also have one or two associated setpoint registers (target output
power, output current, and/or output voltage), as well as a separate ramp rate register which
specifies how fast to move from an existing output power or current level to a new setpoint
target. The programmable ramp rate allows the PCS to smoothly ramp up or ramp down port
power over a programmable time period ranging from tens of milliseconds to minutes.
The Control Methods supported in the
Stabiliti™ Series PCS are listed below.
AC1 Control Methods
IDLE (0x0000)
– factory default
NET (0x0001)
– grid-tied applications only
GPWR (0x0402)
– grid-tied applications only
FPWR (0x0502)
– interactive voltage-following/voltage-forming applications (requires
external islanding switchgear or voltage-forming applications)
DC2/DC3 Control Methods
IDLE (0x0000)
– factory default
NET (0x0001)
MPPT (0x0002)
DCA (0x0301)
DC POWER (0x0401)
Control Method Uses and Restrictions
IDLE Control Method (0x0000)
If a port is not in use, it should be set to the IDLE Control Method. All Converters are shipped
with IDLE as their factory default for safety purposes.
