Sonic Driver Modbus-UFM RTU Slave Meter Instruction Manual

: June 12, 2024
: Sonic Driver

Sonic Driver Modbus-UFM RTU Slave Meter Instruction Manual

Introduction

TM Modbus RTU Slave functionality is implemented on the Sonic Driver on MODBUS WALL ultrasonic flowmeter (MODBUS WALL-UFM). clamp-
Meter settings are fully configurable on the UFM using a Windows based program running on a PC or laptop or an Android app running on a mobile phone. In addition a full range of flow measurements and diagnostics can be read from the meter.
Once installed and commissioned the computer or mobile can be disconnected and the meter wired back to a control room PCL or similar.

Mode

The Modbus RTU protocol is implemented over RS485 hardware.
Mobile connection uses a USB-OTG cable and Modbus interface. PC connection uses a USB A/B cable and a Modbus interface, see figure(1).

Figure(1) Mobile and PC connections

**** Physical connection to the 2-wire bus is via the screw terminals on the UFM board. The terminals are labelled ‘A’ and ‘B’.

Note that some equipment manufacturers label their terminals in other ways,

e.g. ‘+’ and ‘-‘ so the exact order that the wires are connected may be reversed.

There is also a screw terminal for connection of cable screen. This may be connected at either the Master or the Slave UFM if necessary.

1.0 Baud rate

The RS485 baud rate is 19200.

1.1 Parity

The RS485 parity is Even.

1.2 Stop Bits

The RS485 stop bits is 1.

1.3 Modbus Address

The Modbus-UFM Slave address is programmable from 1 to 255. The default Slave address is set to 1.

1.4 Data bits

RS485 serial data is fixed at 8 bits.

1.5 Register format

In the UFM each Modbus register is a 16-bit word, consisting of two 8-bit bytes.

Register data in Modbus messages are packed as 2 bytes per register. The binary contents are right justified in each byte. For each register the first byte contains the high order bits and the second byte contains the low order bits.

A floating-point number is stored as 32 bits using 4 bytes and therefore occupies 2 Modbus registers.

1.6 Representation of floating-point values

The UFM stores floating point values in IEEE 754 single precision format.

The bus Master accesses a floating-point value from any one of 4 different register tables. Each register table represents a different byte order.

Table start	Byte order	Common Description
0x0000	1,0,3,2	Floating-point Little-Endian with byte swap (Default)
0x1000	0,1,2,3	Floating-point Little-Endian Format
0x2000	3,2,1,0	Floating-point Big-Endian Format
0x3000	2,3,0,1	Floating point Big-Endian with byte swap

By reading the first 2 registers of each table the user can determine which format matches their system when a fixed test value of 1234.0 is received.

Modbus Commands

The UFM implements Modbus commands 03, 04, 06 and 16.

Read Holding Registers 03 ****

This function code is used to read from 2 to 110 contiguous holding registers from the UFM. Registers are addressed starting at zero. Therefore holding registers numbered 1-110 are addressed as 0-109.
The Modbus Master specifies a start address and register count.

Read Input Registers 04

This function code is used to read from 2 to 110 contiguous input registers from the flowmeter. Registers are addressed starting at zero. Therefore input registers numbered 1-110 are addressed as 0-109.
The Modbus Master specifies a start address and register count.

Write Single Register 06

This function code is used to write a single register. This function code is used to program integer values in the UFM.
The Master specifies an address and 16-bit data value for write.
The value is an unsigned 16-bit value. Valid values are defined for each register address, see appendix 3
Writing a value of 0x00 to register 60011 will clear the unit’s internal error log.

Write Single Register 16

This function code is used to write multiple registers. This function code is used to program 32-bit floating-point values in the UFM.
The Master specifies an address and 32-bit data value for write.
The value is a pair of unsigned 16-bit values. Valid values are defined for each register address, see appendix 3.

Broadcast address

The UFM supports broadcast address 0.
In broadcast address mode the Modbus master can send a command to all slaves.
No response is sent by the slaves.

Communications Software

There are several communications programs available for download online.
The UFM has been tested using Modbus Poll (for Windows platform) and Modbus Monitor (for Android and Windows platforms).

Appendix 1: Communication Command Structure

Read holding registers| |
---|---|---
| Slave ID| (1 byte)
| Function| (1 byte=03H)
| Start Address| (2 bytes)
| No. of Registers R| (2 bytes)
| CRC code| (2 bytes)
Reply| |
| Slave ID| (1 byte)
| Function| (1 byte)
N = 2R| Byte Count N| (1 byte)
| Hex Data| (N bytes)
| CRC code| (2 bytes)

Appendix 2: Command 03 and 04 UFM Register Map

Modbus Address	Measurement/Variable	Bytes	Format
40001	Fixed test pattern 1234.0	4	IEEE
40002
40003	Flow Velocity (m/s)	4	IEEE
40004
40005	Flow Rate Volumetric (l/min)	4	IEEE
40006
40007	Flow Rate Mass (kg/min)	4	IEEE
40008
40009	Flow Rate Heat (KJ/s)	4	IEEE
40010
40011	Amplifier gain (dB)	4	IEEE
40012
40013	Signal Amplitude (dB)	4	IEEE
40014
40015	Signal Noise (dB)	4	IEEE
40016
40017	SNR (dB)	4	IEEE
40018
40019	Delta Time Difference (ns)	4	IEEE
40020
40021	Upstream Transit Time (us)	4	IEEE
40022
40023	Downstream Transit Time (us)	4	IEEE
40024
40025	Arrival Bin	4	IEEE
40026
40027	Signal Diagnostic 1 (us)	4	IEEE
40028
40029	Signal Diagnostic 2 (ADU)	4	IEEE
40030
40031	Meter Error Code	4	IEEE
40032
40033	Transducer Type (List)	4	IEEE
40034
40035	Transducer Wedge Angle (deg)	4	IEEE
40036
40037	Transducer SOS at 20 deg C (m/s)	4	IEEE
40038
40039	Transducer SOS at 60 deg C (m/s)	4	IEEE
40040
40041	Transducer Crystal Offset (m)	4	IEEE
40042
40043	Transducer Spacing Offset (m)	4	IEEE
40044
40045	Transducer Frequency Code (List)	4	IEEE
---	---	---	---
40046
40047	Transducer Delta Time Offset(ns)	4	IEEE
40048
40049	Transducer K Factor	4	IEEE
40050
40051	Pipe Type (List)	4	IEEE
40052
40053	Pipe SOS (m/s)	4	IEEE
40054
40055	Pipe Outer Diameter (m)	4	IEEE
40056
40057	Pipe Wall Thickness (m)	4	IEEE
40058
40059	Pipe Inner Wall Roughness (m)	4	IEEE
40060
40061	Fluid Type (List)	4	IEEE
40062
40063	Fluid Temperature (deg C)	4	IEEE
40064
40065	Fluid SOS (m/s)	4	IEEE
40066
40067	Fluid Density (kg/m3)	4	IEEE
40068
40069	Fluid Kinematic (cSt)	4	IEEE
40070
40071	Fluid SHC (J/(kg.K))	4	IEEE
40072
40073	Flow Minimum Cut-off (m/s)	4	IEEE
40074
40075	Flow Damping (s)	4	IEEE
40076
40077	Modbus Address	4	IEEE
40078
40079	Corrected SOS (m/s)	4	IEEE
40080
40081	Window Delay (us)	4	IEEE
40082
40083	Zero Tracking (On/Off)	4	IEEE
40084
40085	Zero Calibration (On/Off)	4	IEEE
40086
40087	Dynamic Temperature (On/Off)	4	IEEE
40088
40089	Inlet Temperature (deg C)	4	IEEE
40090
40091	Outlet Temperature (deg C)	4	IEEE
40092
---	---	---	---
40093	Flow Profile K Factor	4	IEEE
40094
40095	Reynolds Number	4	IEEE
40096
40097	Number of Passes	4	IEEE
40098
40099	Tup Method	4	IEEE
40100
40101	Transducer Spacing (m)	4	IEEE
40102
40103	ATA/ETA (%)	4	IEEE
40104
40105	Iout Minimum Value (l/min)	4	IEEE
40106
40107	Iout Maximum Value (l/min)	4	IEEE
40108
40109	Relay Alarm Value (l/min)	4	IEEE
40110

Text Strings, company name (26 chars), model code (26 chars), serial

number (8 chars), HW/SW version (6 chars)

Modbus Address	Text Strings, 2 chars	Bytes	Format
40300	So	2	Word
40301	ni	2	Word
40302	c< >	2	Word
40303	Dr	2	Word
40304	Iv	2	Word
40305	er	2	Word
40306	< >< >	2	Word
40307	< >< >	2	Word
40308	< >< >	2	Word
40309	< >< >	2	Word
40310	< >< >	2	Word
40311	< >< >	2	Word
40312	< >< >	2	Word
40313	MO	2	Word
40314	DB	2	Word
40315	US	2	Word
40316	< >W	2	Word
40317	AL	2	Word
40318	L-	2	Word
40319	UF	2	Word
40320	M< >	2	Word
40321	ST	2	Word
40322	D< >	2	Word
40323	< >< >	2	Word
---	---	---	---
40324	< >< >	2	Word
40325	< >< >	2	Word
40326	10	2	Word
40327	00	2	Word
40328	00	2	Word
40329	00	2	Word
40330	20	2	Word
40331	02	2	Word
40332	00	2	Word

Serial number in the example is 1000000, HW and SW versions are 2.00 and 2.00.

Signal Data Trace Values, as pairs of 8-bit values.

Modbus Address| Signal Data Trace Value Pairs| Bytes| Format
---|---|---|---
| | |
40401| 8-bit data point 0, 8-bit data point 1| 2| WORD
40402| 8-bit data point 2, 8-bit data point 3| 2| WORD
40403| 8-bit data point 4, 8-bit data point 5| 2| WORD
40404| 8-bit data point 6, 8-bit data point 7| 2| WORD
40405| 8-bit data point 8, 8-bit data point 9| 2| WORD
40406| 8-bit data point 10, 8-bit data point 11| 2| WORD
..| …,…| ..| …
..| …,…| ..| …
40649| 8-bit data point 496, 8-bit data point 497| 2| WORD
40650| 8-bit data point 498, 8-bit data point 499| 2| WORD

Appendix 3: Command 06 and 16 Definitions

| Write Single| Write Multiple| 16/32 bit Write| Value| Default| Minimum| Maximum| SI Unit|
---|---|---|---|---|---|---|---|---|---
Value| CMD 06| CMD 16| | | | | | |
Transducer Type| 0| | 16| 1| 1| 0| 3| List| DN40/DM10/DM20/DS10
Transducer Wedge Angle| | 0| 32| 40.000| 40.000| 1.000| 90.000| deg|
Transducer SOS at 20degC| | 2| 32| 2522.000| 2522.000| 500.000| 7000.000| m/s|
Transducer SOS at 60degC| | 4| 32| 2522.000| 2522.000| 500.000| 7000.000| m/s|
Transducer Crystal Offset| | 6| 32| 0.012| 0.012| 0.001| 0.100| m|
Transducer Spacing Offset| | 8| 32| 0.030| 0.030| 0.001| 0.100| m|
Transducer Transmit Code| 1| | 16| 1| 1| 0| 2| | 4/1/2 MHz
Transducer Delta Transit Time Offset| | 10| 32| 0| 0| -2.00E-08| 2.00E-08| s|
Transducer K Factor| | 12| 32| 1.000| 1.000| 0.001| 1000.000| |
Pipe Type| 2| | 16| 0| 0| 0| 3| List| Carbon Steel/Stainless Steel/Copper/PVC
Pipe SOS| | 14| 32| 3230.0| 3230.0| 500.0| 7000.0| m/s|
Pipe Outer Diameter| | 16| 32| 0.0606| 0.0606| 0.01| 6.50| m|
Pipe Wall Thickness| | 18| 32| 0.0032| 0.0032| 0.0005| 0.1| m|
Pipe Inner Wall Roughness| | 20| 32| 0.00001| 0.00001| 0.000001| 0.002| m|
Fluid Type| 3| | 16| 0| 0| 0| 3| List| Water/Petrol/Diesel/Glycol-Water
Fluid Temperature| | 22| 32| 18.000| 18.000| 0.000| 150.000| deg C|
Fluid SOS| | 24| 32| 1475.000| 1475.000| 50.000| 3000.000| m/s|
Fluid Density| | 26| 32| 998.520| 998.520| 50.000| 3000.000| kg/m2|
Fluid Kinematic| | 28| 32| 1.080| 1.080| 0.001| 40000.000| cSt|
Fluid Specific Heat Capacity| | 30| 32| 4184.000| 4184.000| 10.000| 10000.000| J/(g.K)|
Minimum Flow Cut Off| | 32| 32| 0.025| 0.025| 0.000| 1.000| m/s|
Flow damping| 4| | 16| 10| 10| 0| 255| s|
---|---|---|---|---|---|---|---|---|---
Modbus Address| 5| | 16| 1| 1| 1| 255| |
Transducer Wedge Corrected SOS| | 34| 32| 2522.000| 2522.000| 500.000| 7000.000| m/s|
Sampling Window delay| 6| | 16| 169| 169| 11| 65535| us|
Zero Tracking On/Off| 7| | 16| 1| 1| 0| 1| On/Off
Zero calibration On/Off| 8| | 16| 0| 0| 0| 1| On/Off
Dynamic Temperature On/Off| 9| | 16| 0| 0| 0| 1| On/Off
Number of Passes| 10| | 16| 4| 4| 1| 16| |
Tup Method| 12| | 16| 3| 3| 0| 4| List| Method 0, 1, 2, 3, 4
Iout Minimum Value| | 36| 32| 0| 0| -1000000.0| 1000000.0| l/min|
Iout Maximum Value| | 38| 32| 160.0| 160.0| -1000000.0| 1000000.0| l/min|
Relay Alarm Value| | 40| 32| 40.0| 40.0| -1000000.0| 1000000.0| l/min|