flow parameters. These selections includes alarm status and diagnostic information such as input status and calculation
status. Alarms can be defined as low alarms, high alarms, or configured with both low and high setpoints.
A bit value of 1 indicates an alarm condition.
For details on configuring an alarm, see the Scanner 3100 Web Interface User Manual.
Units
Scanner 3100 holding registers allow users to read data in terms of measurement units specified by the installed Modbus
map. These units are different from Scanner 3100 local history logs returned as Enron records.
Enron Interval, Daily and Event Registers
The Enron registers are used for polling the interval, daily, and event log records from Scanner 3100 archives. The Enron
registers have a read-only access type. The Scanner 3100 stores flow run data in two local flow run archives (Flow Run
1 and Flow Run 2), each of which can store up to 58 user-configurable parameters and three system-defined parameters
(date, time and Status).
The Scanner 3100 also stores data for up to 20 slave archives, and each archive can contain up to 14 user-configurable
parameters and two system-defined parameters (date and time).
If a host has difficulty reading large record widths that can exist in local flow run logs, the Scanner 3100 can be config-
ured to transmit logs with smaller record widths (for example, Scanner 3100 can transmit 16 parameters (13 user-speci-
fied registers and three system-defined parameters: date, time and status).
For details on configuring the local archive to transmit the smaller record widths, see the Scanner 3100 Web Interface
manual.
Enron Interval/Daily Record Format
The interval and daily record contents are user-configurable. The following table shows some of the critical parameters
included in the Scanner 3100 Enron Modbus record format. To view the complete list of parameters, refer to the Scanner
3100 Web Interface Manual. If desired, the response time for the Enron archive can be reduced by limiting the number of
items included in the record using the communications configuration selections in the Scanner 3100 web interface.
Parameter
Data Type
Record Date (MMDDYY)
FP
Record Time (HHMMSS)
FP
Status
FP
FlowRun1_GasVolumeTotal
FP
FlowRun1_GasMassTotal
FP
FlowRun1_GasEnergyTotal
FP
FlowRun1_RunTime
FP
FlowRun1_StaticPressure_Value
FP
FlowRun1_Temperature_Value
FP
FlowRun1_DifferentialPressure_Value
FP
Enron Slave Record Format
Slave logs transmitted to the Scanner 3100 are generally stored in the base units used for Scanner 2x00 Series calcula-
tions as defined by Scanner 2x00 Series protocol. The exception is analog input logs, which are stored in the configured
unit of the measurement category to which they belong (static pressure, differential pressure, etc.). Slave device base
units may vary from the units of the Scanner 3100.
When decoding the register values, pay special attention to the data types shown above to ensure that the fixed values are
properly identified. There are two fixed values (date and time) in Scanner 2x00 Series slave records, and three fixed val-
ues (date, time, and status) in Scanner 3100 records. Refer to the protocol manual for the appropriate Scanner slave de-
vice to determine the date type for specific records.
89
Scanner 3100 Modbus Protocol
Section 1
