11
F O R M
DVR
®
2400 and DVR
®
2500 Digital Voltage Regulator
Installation, Operation and Maintenance Manual
SB0056E
Revised
November 2018
Regal Beloit America, Inc.
100 East Randolph Street
Wausau, WI 54402-8003
www.regalbeloit.com/Brands/
Marathon-Generators
Example:
A field current set point of 1.000 Adc with the application of a
11.00 mA signal will result in a total field current of 0.500 Adc.
When in VAR:
The application of a 4 mA to 20 mA signal corresponds to a percentage
offset of up to +/- 30.0% to the VAR set point.
Example:
A programmed VAR regulation set point of 50.0% with an
auxiliary input scale factor of 30.0% and an auxiliary input of 9.33 mA
will result in a –10.0% offset to the VAR set point. Therefore, the regula-
tor will regulate to 40.0% of rated VARs.
When in PF:
In the PF regulation mode, the application of a 4 mA to 20 mA signal cor-
responds to an offset of up to +/- 0.300 PU to the power factor set point.
Example:
A programmed power factor regulation set point of 0.950
(lagging power factor) with an auxiliary input scale factor of 30.0% and an
auxiliary input of 9.33 mA will result in a –0.100 offset to the power factor
set point. Therefore, the regulator will regulate to a power factor of -0.950.
In this case, the power factor has gone from a lagging to a leading state.
Auxiliary - Dynamic Slope (DVR
®
2500 regulator only):
The 2500 regulator provides a mode in which an auxiliary voltage of 0 to
+5V supplied between terminals P1-4 (AU+) and P1-5 (AU-) can be used
to influence the under-frequency slope multiplier from 1.0 - 5.0 or 5.0 -
1.0 based on dynamic slope polarity while in AVR1 and AVR3 regulation
modes. See Figure 4-2.
Figure 4-2. Dynamic Slope Multiplier
LOAD SHARING
Note: The machine nameplate rated power, rated power factor, CT
Ratio and PT Ratio (if applicable) MUST be entered to calculate the
proper rated reactive power for the droop reference.
The regulator provides a reactive droop compensation feature to enable
reactive load sharing during parallel generator operation. When this feature
is enabled, the regulator calculates the reactive portion of the generator
load using the sensed generator output voltage and current quantities and
then modifies the voltage regulation set point accordingly.
A unity power factor generator load results in almost no change in gen-
erator output voltage. A lagging power factor generator load (inductive)
results in a reduction of generator output voltage. A leading power factor
generator load (capacitive) results in an increase of generator output volt-
age.
Droop is adjustable up to 10.0% with rated reactive power (VAR’s) and
rated power factor. The effect of droop on the set point is displayed in the
DVRPortal
™
software. The droop feature is enabled and disabled through
the DROOP_OFF contact input circuit (terminals P1-9 (DRP) and P1-11
(GND). When single-phase current sensing is used, the droop function re-
sponds to phase B current. When three-phase current sensing is used,
the droop function responds to the average phase current. Reactive load
sharing in AVR1, AVR3, VAR and PF modes.
GENERATOR SOFT START
The regulator incorporates an adjustable soft start feature that controls the
time for generator voltage to ramp to the regulation set point. This feature
is enabled in AVR3 and AVR1 regulation modes. The ramp rate is adjust-
able from 2 to 120 seconds (default of 3 seconds). This adjustment is made
through the portal and cannot be made through the HMI. The Generator
Under Frequency feature is also active during Generator Soft Start and
takes priority in control of the generator voltage.
