Maxim Integrated 6612_OMU_S2+2_URT_V1_14 - Manual (Page 40)

6612_OMU_S2+2_URT_V1_14 Firmware Description Document UG_6612_017
40 Rev. 1.0
6 Configuration Parameter Entry
6.1 MPU Parameters
Table 8 lists the MPU parameters configurable by Firmware 6612_OMU_S2+2_URT_V1_14.
Table 8: MPU Parameters
MPU
Parameter
Location
(hex)
LSB Default Comment Example
VMAX A A0 mVrms +471.500
External rms voltage
corresponding to 250 mVpk at the
VA input of the 78M6612. It must
be set high enough to account for
overvoltages. Usually set to
471.500 V (471.500d).
If only using a 120V
system, the user can set
VMAX A to about 2x the
maximum voltage for added
resolution. Set VMAX A to
270V:
)A0=+270.000
Starting IA A1 mArms +0.007
Minimum current value to be
measured on the IA input.
Currents below this value will be
ignored. Also known as CREEP
IA.
Default setting is 7 mA. If
start current on channel A
desired is 10 mA:
)A1=+0.010
IMAX A A2 mArms +52.000
External rms current
corresponding to 250 mVpk at the
IA input of the 78M6612.
The default is set to 52
Amps for overhead. For
added margin, in a system
using current shunts IMAX
could be changed as
follows:
IMAX= (Vpk/
√2)/R
shunt
For a 4 m
Ω current shunt
IMAX=44.19 Amps
To set IMAX A:
)A2=+44.190
Starting IB A3 mArms +0.007
Minimum current value to be
measured on the IB input.
Currents below this value will be
ignored. Also known as CREEP
IB
Default setting is 7 mA. If
start current on channel B
desired is 10 mA:
)A3=+0.010
IMAX B A4 mArms +52.000
External rms current
corresponding to 250 mVpk at the
IB input of the 78M6612.
The default is set to 52
Amps for overhead. For
added margin, in a system
using current shunts IMAX
could be changed as
follows:
IMAX= (Vpk/
√2)/R
shunt
For a 4 m
Ω current shunt
IMAX=44.19 Amps
)A4=+44.190
Unused A5 – – Unused