Basler Electric DECS-400 - Manual (Page 45)

9369700990 Rev R 33
Ethernet Port
A rear-panel, RJ-45 connector, designated Com 3, enables communication with the DECS-400 over a
10BASE-T Ethernet network.
Modem
An internal telephone modem enables an off-site PC operating BESTCOMS software to dial into a DECS-
400 and view DECS-400 settings, metering values, and system status information. Modem access is
read-only; this prevents system control or the changing of DECS-400 settings. Information about initiating
modem communication is provided in the BESTCOMS Software chapter.
The FCC part 68 approved modem connects through a rear-panel, RJ-11 connector designated J1. The
modem communication baud rate is fixed at 9600.
Power Supply
DECS-400 units with a style number of XLXX, accept nominal operating power of 24 Vdc or 48 Vdc at
terminals C4 (BATT–) and C5 (BATT+). DECS-400 units with a style number of XCXX have two operating
power inputs. One input accepts 125 Vdc at terminals C4 (BATT–) and C5 (BATT+). A second input
accepts 120 Vac at terminals C2 (N) and C3 (L). Refer to the Specifications chapter for the acceptable
input voltage ranges.
The power supply provides 5 Vdc,
±12 Vdc, and 24 Vdc operating power for DECS-400 circuitry and ±12
Vdc operating power for the Field Isolation Module.
Startup Functions
DECS-400 startup functions include a soft start function, field flashing function, voltage matching, and a
buildup failure annunciation function.
Soft Start Function
During startup, the soft start function prevents voltage overshoot by controlling the rate at which the
generator terminal voltage builds toward the setpoint. Soft start is active in AVR (automatic) and FCR
(manual) control modes. During system startup, the voltage reference adjustment is based on two
parameters: level and time. The Soft Start Level is adjustable from 0 to 90%. Soft Start Time is adjustable
from 1 to 7,200 seconds. Figure 5 illustrates a plot of the voltage reference when the soft start level is
30%, the soft start time is 8 seconds, and the voltage setpoint is at 100%.
Field Flash/Buildup
During startup, the field flashing/buildup function applies and removes field flashing from an external field
flashing source. Field flashing/buildup is active in AVR (Auto) and FCR (Manual) control modes. During
system startup, the application of field flashing is based on two parameters: level and time. The field flash
dropout level is adjustable from 0 to 100% of the active mode setpoint and determines when field flashing
is removed. The maximum field flash time is adjustable from 1 to 50 seconds and defines the maximum
duration that field flashing is applied. In FCR control mode, the field flash dropout level is expressed as a
percentage of the field current setpoint and uses the field current level to determine when buildup has
occurred. In AVR control mode, the field flash dropout level is expressed as a percentage of the generator
voltage setpoint and uses the generator voltage level to determine when buildup has occurred.
DECS-400 Functional Description