S A G E M E T E R I N G , I N C .
O p e r a t i o n s a n d I n s t r u c t i o n M a n u a l
60
REV. 16-SIP/SRP
SAGE REGISTER INDEX VALUES
D
ATA ADDRESS
TYPE VALUE SIZE INDEX DESCRIPTION
Byte slave_ad 1 BYTE 1 Modbus Slave Address*
fl
oat flow_rate; 1 IEEE754 578 actual flow rate
fl
oat flow_temp; 1 IEEE754 580 process temperature
float rtd_mWatts; 1 IEEE754 582 sensor power reading
float rtd_res; 1 IEEE754 584 actual sensor probe resistance
fl
oat ref_res_r; 1 IEEE754 586 actual temperature probe resistance
integ totalizer; 1 uLONG 312 actual displayed total
*
NOTE: Sage Prime Meters are factory programmed with the MODBUS slave address = 48 (0x30).
It may be extremely useful to be able to write to an unknown slave address with a simple broadcast
command. Be sure only one Sage Prime is connected during any broadcast writes using slave
a
ddress = 0.
Writing into unspecified registers (not defined above)
can render the unit non-functional or overwrite fac-
tory calibration data yielding incorrect operation.
EXAMPLE MODBUS PACKET
Query
This packet will request of the addressed slave to
respond by sending back the contents of registers
578 to 582 (inclusive). Three registers: flow rate
through RTD mWatts in IEEE754 floating point
format.
0x31 – SAGE PRIME SLAVE ADDRESS (0x31 Hex = 49 Decimal default)
0x04 – READ INPUT REGS FUNCTION CODE
0x02 – STARTING REGISTER HI BYTE (0x01 = 256, 0x02 = 512, 0x03 = 768)
0x42 – STARTING REGISTER LO BYTE (512 + 66 = register access = 578)
0x00 – COUNT MSB (ALWAYS ZERO)
0x06 – COUNT OF ALL DESIRED REGISTERS
0xD5 – CRC HI BYTE
0x85 – CRC LO BYTE