MCP3909RD-3PH1 Microchip Technology, MCP3909RD-3PH1 Datasheet - Page 36

• Manufacturer Part Number: MCP3909RD-3PH1
• Description: REF DESIGN MCP3909 3PH ENGY MTR
• Manufacturer: Microchip Technology

Specifications of MCP3909RD-3PH1

• Main Purpose: Power Management, Energy/Power Meter
• Embedded: No
• Utilized Ic / Part: MCP3909, PIC18F2520, PIC18F4550
• Primary Attributes: 3-Ph, 220 VAC, In Case, LCD, USB, GUI
• Secondary Attributes: Opto-Isolated Interface for Safety
• Operating Voltage: 220 V
• Operating Current: 5 A
• Description/function: Energy Meter
• For Use With/related Products: MCP3909
• Lead Free Status / RoHS Status: Not applicable / Not applicable

MCP3909 3-Phase Energy Meter Reference Design
3.5
3.5.1
3.5.2
3.5.3
3.5.4
3.5.5
DS51643B-page 32
CALIBRATION REGISTERS
PHy_DELAY
PHy_I_RMS_OFF
PHy_V_RMS_OFF
PHy_I_RMS_GAIN (NOT IMPLEMENTED)
PHy_V_RMS_GAIN (NOT IMPLEMENTED)
The calibration register set contains all of the offset, gain, LSB adjust, phase delay, and
calibration output pulse adjustment settings. The values to be placed in these
configuration registers come during meter calibration and can be automatically
generated using the “3-Phase Meter Calibration Software” available for download on
Microchip’s website.
REGISTER 3-25:
Phase y delay, signed 8-bit value, ±2.8125 degrees
(±130 µs for 60 Hz, ±156 µs for 50 Hz)
REGISTER 3-26:
value should be similar to the ADCs noise squared. At a gain of 1, the noise will be
about 1 LSB, 2 LSBs at a gain of 2 and 6 LSBs at a gain of 8 and 11 LSBs at a gain of
16. There may be other sources of noise. Using the square of the offset allows for
higher accuracy. The value will be added before the square root is taken when
calculating the final RMS value.
REGISTER 3-27:
Square of offset for phase y RMS voltage reading, signed 8-bit value. Note that this
value should be similar to the ADCs noise squared. For the voltage channel, the noise
will be about 1 LSB. There may be other sources of noise. Using the square of the offset
allows for higher accuracy. The value will be added before the square root is taken
when calculating the final RMS value.
NOT IMPLEMENTED IN THIS FIRMWARE/SOFTWARE RELEASE.
NOT IMPLEMENTED IN THIS FIRMWARE/SOFTWARE RELEASE.
Square of offset for phase y RMS current reading, signed 16-bit value. Note that this
PHA_I_RMS_OFF
PHB_I_RMS_OFF
PHC_I_RMS_OFF
PHA_V_RMS_OFF
PHB_V_RMS_OFF
PHC_V_RMS_OFF
PHC_DELAY
PHA_DELAY
PHB_DELAY
Name
Name
Name
PHY_DELAY REGISTER
PHY_I_RMS_OFF REGISTER
PHY_V_RMS_OFF REGISTER
Bit
8
8
8
Bit
16
16
16
Bit
16
16
16
Address
0x140
0x141
0x142
Address
0x14A
0x144
0x148
Address
0x14A
0x14E
0x146
R/W
R/W
R/W
Cof
R/W
R/W
R/W
Cof
R/W
R/W
R/W
Cof
© 2008 Microchip Technology Inc.