7
GF U3000 V2 Ultrasonic Flowmeter
Modbus Supplement to the operating instructions
The management system programmer may choose to use the Time and Date associated with the GF U3000 V2 Ultrasonic Flowmeter,
or use the Time and Date associated with their system time by simply reading a block of registers starting at either offset 100 or
offset 104.
All data in the register set changes once each second. All registers should be read at the same time; however, it is possible to halt
the update of these registers before reading to allow the management system to read individual registers at its leisure. In this way,
it is guaranteed that all data points during the read will pertain to the same set (the same second).
It should be noted that if reading these registers takes more than a second, the time and Date stamp will jump and data for the mis-
sing second will be lost. Readings must be made in real time.
GF U3000 V2 Ultrasonic Flowmeter Modbus Register Map.
Reg
Num
Reg
Idx
Use
Type
Notes
Access1 Source/Comment
1
0
Check
value /
Interface
version
uint16
0x5A00
R
This is a check value and an interface
version number. This version is zero. All
values start at the base 0x5A00.
2
1
Device ID uint16
GF U3000 V2 Ultrasonic
FlowmeterC=0x0035
GF U3000 V2 Ultrasonic
FlowmeterHC=0x0036
GF U3000 V2 Ultrasonic
FlowmeterCO=0x0037
GF U3000 V2 Ultrasonic
FlowmeterHCO=0x0038
R
GF U3000 V2 Ultrasonic Flowmeter
variant.
3,4
2,3
Serial
Number
uint32
E.g., 20111
0x0000, 0x4E8F
R
Unit Serial Number
5
4
Regime
uint16
Measurement Regime:3
RW
0 = Metric1
1 = Imperial
2 = US Imperial
3 = Metric2
> 3 = reserved (defaults to Metric1)
Temperature Regime: 1
0 = ⁰C,
1 = ⁰F
Reserved:11
For future use.
6
5
Instru-
ment
Control
Flags
uint16
Lock-out updates:1
RW
Writable from MBM only. 1= stop
updating registers (excludes action/
response bits)
Lock screen mode:1
Can be set/reset from MBM. Set Lock
screen mode active= 1
Update Lock Screen Mode:1
Action/Response bit. 1=update; set to 0
by instrument when complete.
Save Measurement Regime:1
Save the current measurement
regimes. (including temperature)
Reserved:12
7
6
Instru-
ment
General
Flags
uint16
Screen lock mode active:1
R
Local screen is locked
Remote Lockout:1
Local device has locked out remote
(MBM) write updates (excluding regime
changes)
