Rockwell Automation 1395 DC Drive, 800-1250 Hp, FRN 5.XX-9.30 - Manual (Page 145)

Chapter 5
Programming Parameters
5-54
Parameter 685 – Field Current at 1.0 Flux [Fld I @ 1/0 FLUX]
Internal units : 4096 = 1000h = 100% rated field current
Programming Terminal units: Percent rated field current
Minimum Value: 0%
Maximum Value: 100%
Default Value: 100%
Description: This is the eighth entry in a 9 element lookup table for
converting flux reference commands to field current reference. The
lookup conversion is used to linearize the field current reference with
respect to flux. This value corresponds to the field current required to
produce 100 % rated armature volts when the motor is running at base
speed and is in terms of internal units where 4096 = 100% rated field
current. This should always be 100%.
Parameter 686 – Field Weakened Speed [Fld Weaken Speed]
Internal units : 4096 = 1000h = base motor speed
Programming Terminal units: RPM
Minimum Value: base speed/8
Maximum Value: 6 x base speed
Default Value: base motor speed
Description: This parameter specifies the speed at which field
weakening control and CEMF regulation begins. Field weakening
and CEMF operation is enabled by setting bits in the Flux Mode
Select (Parm 627). A typical value used for the Field Weakened
Speed, is base motor speed.
Parameter 687 – CEMF Reg Preload [CEMF Reg Preload]
Internal units : 4096 = 1000H = 1 pu Flux
Programming Terminal units: Percent of unity flux
Minimum Value: –799.9%
Maximum Value: 799.9%
Default Value: 0
Description: This parameter is associated with the CEMF reset
function (bit 5) in parameter 627. When the reset bit is set high, the
integral term and output of the CEMF regulator will be set to the
value in this parameter. This parameter is scaled so that 1 pu flux =
4096.