Setra Systems, Inc.

HeadStart™ Read & Write Registers Help

Communications
Set CT Values
Read & Write Registers
Communications Setup
Firmware Update
Setra Power Patrol Operating Instructions
Setra Power Squad 24 Operating Instructions

Read & Write Registers

The Read & Write Registers tab allows you to read or write a single register of your choosing on the meter. Enter the register address and click the Read Modbus Register button to read the value at that address. Enter the register address and a value and click the Write Modbus Register button to write that value to the specified register.

The Read Data Scalar button reads the Data Scalar register and displays it. The Data Scalar determines how values are scaled before display. The Write Data Scalar button lets you change the scalar by entering a new value in minutes. The power needs to be turned off and on after changing the value for it to take effect.

The Read Demand Window Size button reads the Demand Window Size register and displays it. The Demand Window Size determines how big the window is in minutes during which the peak load is measured. The Write Demand Window Size button lets you change that value by entering a new value in minutes. The power needs to be turned off and on after changing the value for it to take effect.

If a button is greyed out (disabled) and says that no device is connected, return to the communications tab and establish a connection with the meter, then try again.


Table 1. Data Scalar and Resolution of Modbus Values for Registers 44001 thru 44061
Register 44064kW/kWh DemandkVAR/kVARhkVA/kVAhPower FactorAmpsVolts
0.00001 .00001.00001.010.01 A0.1V
1.001.001.001.010.1 0.1
2.01.01.01.010.1 0.1
3.1.1.1.010.1 0.1
41 11.011 A1 V
5101010.0111
>=6100100100.0111


Table 2. Modbus Register Assignments for Setra Power Patrol.
RegisterModbusDetailed Description
Net True Energy LSW44001System Total Net True Energy LSW (kWh)
Net True Energy MSW44002System Total Net True Energy MSW (kWh)
Total True Power44003System Total True Power (kW)
Peak Demand44004Max Average power window (KW)
Present Demand44005Average power (KW) (most recent window)
Maximum Instantaneous kW44006System Maximum Instantaneous kW
(Highest 500mS kW)
Minimum Instantaneous kW44007System Minimum Instantaneous kW
(Lowest 500mS kW)
Net Reactive Energy LSW44008System Total Net Reactive Energy LSW (kVARh)
Net Reactive Energy MSW44009System Total Net Reactive Energy MSW (kVARh)
Total Reactive Power44010System Total Reactive Power (kVAR)
Total Apparent Energy LSW44011System Total Apparent Energy LSW (kVAh)
Total Apparent Energy MSW44012System Total Apparent Energy MSW (kVAh)
Total Apparent Power44013System Total Apparent Power (kVA)
Total Displacement Power Factor44014System Total Power Factor (PF)
Total Apparent Power Factor44015System Total Power Factor (PF)
Total Current44016Total current in all phases.
Voltage Line - Line44017Voltage Line to line (Volts) Average.
Voltage Line - Neutral44018Voltage Line to neutral (volts) Average.
Voltage Phase A - B44019Individual Phase to Phase Voltages
Voltage Phase B - C44020 
Voltage Phase C - A44021 
Line Frequency44022Line Frequency (Hz)
True Energy Phase A LSW44023Individual Phase True Energy LSW (kWh)
True Energy Phase A MSW44024Individual Phase True Energy MSW (kWh)
True Energy Phase B LSW44025 
True Energy Phase B MSW44026 
True Energy Phase C LSW44027 
True Energy Phase C MSW44028 
True Power Phase A44029Individual Phase True Powers (kW)
True Power Phase B44030 
True Power Phase C44031 
React Energy Phase A LSW44032Individual Phase Reactive Energy LSW (kVARh)
React Energy Phase A MSW44033Individual Phase Reactive Energy MSW (kVARh)
React Energy Phase B LSW44034 
React Energy Phase B MSW44035 
React Energy Phase C LSW44036 
React Energy Phase C MSW44037 
React Power Phase A44038Individual Phase Reactive Powers (kVAR)
React Power Phase B44039 
React Power Phase C44040 
Apparent Energy Phase A LSW44041Individual Phase Apparent Energy LSW (kVAh)
Apparent Energy Phase A MSW44042Individual Phase Apparent Energy MSW (kVAh)
Apparent Energy Phase B LSW44043 
Apparent Energy Phase B MSW44044 
Apparent Energy Phase C LSW44045 
Apparent Energy Phase C MSW44046 
Apparent Power Phase A44047Individual Phase Apparent Powers (kVA)
Apparent Power Phase B44048 
Apparent Power Phase C44049 
dPF Phase A44050Individual Phase displacement Power Factor (PF)
dPF Phase B44051 
dPF Phase C44052 
aPF Phase A44053Individual Phase apparent Power Factors (PF)
aPF Phase B44054 
aPF Phase C44055 
Current Phase A44056Individual Phase Currents (A)
Current Phase B44057 
Current Phase C44058 
Voltage Phase A_N44059Individual Phase to Neutral Voltages (V)
Voltage Phase B_N44060 
Voltage Phase C_N44061 
Time Since Reset LSW44062Seconds since KWH register was reset. LSW
Time Since Reset HSW44063Seconds since KWH register was reset. MSW
Data Scalar44064See Table 1
Volts Scalar44065For use with step-down transformer (not used 6-2007)
Amps Scalar44066For use with primary CTs (not used 6/2007)
Demand Window Size44067In Minutes (1 to 60)
CT Value44068In Amps X10
Firmware Major Rev. Number44069 
Firmware Minor Rev. Number44070