Micronics U1000MKII-HM User manual

Micronics U1000MKII-HM User Manual
Issue X.X July 18
Page 1
Micronics U1000MKII-HM
Clamp On Ultrasonic Heat Meter
User Manual
Micronics Ltd, Knaves Beech Business Centre, Davies Way, Loudwater,
High Wycombe, Bucks HP10 9QR
Telephone: [phone] E-mail: [email protected]
www.micronicsflowmeters.com

Micronics U1000MKII-HM User Manual
Issue X.X July 18
Page 2
Table of Contents
1General Description..................................................................................................................................... 3
2Quick Start Procedure ................................................................................................................................. 4
3How Does It Work?...................................................................................................................................... 5
4User Interface .............................................................................................................................................. 6
4.1 Key Switches ....................................................................................................................................... 6
5Installing The U1000MKII-HM ..................................................................................................................... 7
5.1 Preparation .......................................................................................................................................... 8
5.2 Sensor Separation............................................................................................................................... 8
5.3 Attaching The U1000MKII-HM To The Pipe...................................................................................... 10
5.4 Adaptors For Small Pipes.................................................................................................................. 11
5.5 Attaching The Temperature Sensors................................................................................................. 12
5.6 U1000MKII-HM Interface Cables....................................................................................................... 13
5.7 Connecting The U1000MKII-HM To The Supply............................................................................... 13
5.8 Pulse Output Connection................................................................................................................... 14
5.9 Modbus Connections......................................................................................................................... 14
5.10 Cable Screen..................................................................................................................................... 14
6Powering Up For The First Time ............................................................................................................... 15
6.1 How To Enter The Pipe ID................................................................................................................. 17
6.2 Pulse Output...................................................................................................................................... 18
6.2.1 Volumetric Mode........................................................................................................................ 18
6.2.2 Frequency Mode........................................................................................................................ 18
6.2.3 Energy Mode ............................................................................................................................. 18
6.2.4 Flow Alarm –High/Low Flow or Signal Loss ............................................................................. 18
6.3 Modbus.............................................................................................................................................. 19
7Subsequent Power-ON Sequence ............................................................................................................ 21
8Information Screens................................................................................................................................... 21
9Password Controlled Menus...................................................................................................................... 22
9.1 General Procedure For Changing Menu Settings ............................................................................. 22
9.1.1 Selection Menus ........................................................................................................................ 22
9.1.2 Data Entry Menus...................................................................................................................... 22
9.2 User Password Controlled Menu Structure ....................................................................................... 22
10 Diagnostics Menu .................................................................................................................................. 28
11 Relocation Of Guide Rail....................................................................................................................... 30
12 Appendix I –U1000MKII-HM Specification ........................................................................................... 31
13 Appendix II –Default Values ................................................................................................................. 33
14 Appendix III –Error and Warning Messages......................................................................................... 34
13 Declaration of conformity ………………………….……………………………………………...……………..36

Micronics U1000MKII-HM User Manual
Issue X.X July 18
Page 3
1 General Description
•Fixed installation, clamp-on heat meter
•Easy to install
•Requires the minimum of information to be entered by the user
•Electronics and guide rail housings form an integral unit
•Attached to the pipe using the supplied jubilee clips
•Power to the unit is provided by an external 12 - 24V ac/dc power supply (7VA minimum)
•Operates on steel, stainless steel, copper and plastic pipes with IDs in the range 20mm
(0.8”) to 165mm (6.5”) depending on product purchased
•Simple to install temperature sensors
•Compact, rugged and reliable, the U1000MKII-HM has been designed to provide sustained
performance in industrial environments
.
U1000MKII HM standard features include:
▪2 line x 16 character LCD with backlight
▪4-key keypad
▪Isolated pulse output
▪Universal guide rail for setting pre-assembled transducers
▪Two sets of self-adhesive Gel pad acoustic couplant
▪Dual PT100 type temperature sensors (standard cable length 3m)
▪Continuous signal monitoring
▪Password protected menu operation for secure use
▪Operates from external 12 to 24Vac or dc power supplies
▪Small pipe adaptors
Options
•Select Pipe range
➢20mm inside diameter to 114mm inside diameter pipe
➢115mm inside diameter to 165mm inside diameter pipe
•Available as Modbus heatmeter
•Available as Pulse only heat meter
Typical applications
▪Hot water metering and flow measurement
▪Flow measurement for Energy Metering
▪Chilled water metering and flow measurement

Micronics U1000MKII-HM User Manual
Issue X.X July 18
Page 4
2 Quick Start Procedure
The following procedure details the steps required to set up the heat meter. See the sections
referred to if you are unsure about how to install the instrument.
1. Wire the electronics up to a 12 to 24V ac or dc power supply (7VA minimum per instrument)
via the Blue and Brown wires. (See Section 5.7).
2. Establish a suitable location for the flow meter on a straight length of pipe clear of bends and
valves or similar obstructions. (See Sections 5 and 5.1).
3. Determine the pipe internal diameter and material.
4. Either use the table in the manual, or power up the instrument to determine the correct
separation code. (See Sections 5.2 or 6).
5. Set the sensors to the correct separation by adjusting the sensor holding screws so the
sensor can slide in the slot. (See Section 5.2).
6. Select any adaptors needed for pipes with an outside diameter of less than 60mm, inside
diameter will typically be less than 50mm. (See Section 5.4).
7. Apply the Gel pads to the sensors and mount the guide rail on the pipe using the banding
provided, then remove the sensor holding screws. (See Section 5.3).
8. Plug in the flow and temperature sensors and check that flow and temperature readings can
be obtained. (See sections 6 and 7.1). The electronics can be left resting on the guide rail
and fully clipped down later once all measurements have been checked.
9. Place the temperature sensors touching each other. Wait for the temperature readings to
stabilize, indicated by no change for 1 minute. Then zero the temperature sensors. (See
Section 5.5).
10. Attach the temperature sensors on to the pipe using the self-adhesive pads. Then use the
supplied banding to secure the sensor to the pipe. Don’t overtighten the banding. The
sensor must be in good thermal contact with the pipe and the leads must not be under any
strain. (See Section 5.5).
11. Once good readings have been obtained any further changes, such as selecting different
units, can be made via the User Menu. (See Section 7).
12. Clip the electronics assembly on to the guide rail and tighten screw to complete the
assembly.
13. If the Modbus interface is being used then the address, and data rate, and configuration of
the instrument must be set using the User Menu. (See Section 7). The default address is 1,
the default data rate is 38400 baud, and the default comms configuration is 8-None-2.

Micronics U1000MKII-HM User Manual
Issue X.X July 18
Page 5
3 How Does It Work?
The U1000MKII-HM is a clamp-on, ultrasonic flowmeter that uses a cross correlation transit time
algorithm to provide accurate flow measurements.
An ultrasonic beam of a given frequency is generated by applying a repetitive voltage pulse to the
transducer crystals. This transmission goes first from the Downstream transducer to the Upstream
transducer (red) as shown in the upper half of Figure 1. The transmission is then made in the
reverse direction, being sent from the Upstream transducer (red) to the Downstream transducer
(blue) as shown in the lower half of Figure1. The speed at which the ultrasound is transmitted
through the liquid is accelerated slightly by the velocity of the liquid through the pipe. The
subsequent time difference T1 –T2 is directly proportional to the liquid flow velocity.
The two temperature sensors measure the difference in temperature between inlet and outlet of the
flow system being monitored. The temperature difference, in combination with the volume of water
that has flowed through the system, is then used to calculate the energy transferred to or from the
water.
Figure 1 Principle of Transit-Time operation

Micronics U1000MKII-HM User Manual
Issue X.X July 18
Page 6
4 User Interface
Figure 2 illustrates the U1000MKII-HM user interface comprising:-
•One 2 line x 16 character LCD with backlight
•Four tactile key switches
•Two LEDs
4.1 Key Switches
kWh LED is illuminated when the Energy pulse is enabled.
Pulse LED is illuminated when the Pulse, Frequency or Alarm functions are
eneabled.
Selection key. Allows the user to select between options on the
display.
Used to decrement the value of each digit in numeric entry fields.
>
V
Figure 2 U1000MKII-HM User Interface
Used to increment the value of each digit in numeric entry fields.
Used to enter the selection displayed or terminate the data
entry. Pressing this key can also take the user to a sub menu or
to the Flow Reading screen.
Λ


Micronics U1000MKII-HM User Manual
Issue X.X July 18
Page 7
5 Installing The U1000MKII-HM
Figure 3 Location of Transducers
For optimum reliability on boiler applications, the flow measurement needs to be made on the cold
side of the system. For optimum reliability in chiller applications, the flow measurement needs to be
made on the warmer side of the system, making sure sensors are positioned as in figure 3 above.
In many applications an even flow velocity profile over a full 360° is unattainable due, for example,
to the presence of air turbulence at the top of the flow and possibly sludge at the bottom of the pipe.
Experience has shown that the most consistently accurate results are achieved when the
transducer guide rails are mounted at 45°with respect to the top of the pipe.
The U1000MKII-HM equipment expects a uniform flow profile, as a distorted flow will produce
unpredictable measurement errors. Flow profile distortions can result from upstream disturbance
such as bends, tees, valves, pumps and other similar obstructions. To ensure a uniform profile the
transducers must be mounted far enough away from any cause of distortion such that it no longer
has an effect.
To obtain the most accurate results the condition of both the liquid and the pipe must be suitable to
allow ultrasound transmission along the predetermined path. It is important that liquid flows
uniformly within the length of pipe being monitored, and that the flow profile is not distorted by any
upstream or downstream obstructions. This is best achieved by ensuring there is a straight length of
pipe upstream of the transducers of at least 20 times the pipe diameter, and 10 times the pipe
diameter on the downstream side, as shown in Figure 3. Flow Measurements can be made on
shorter lengths of straight pipe, down to 10 diameters upstream and 5 diameters downstream, but
when the transducers are mounted this close to any obstruction the resulting errors can be
unpredictable.
Key Point: Do not expect to obtain accurate results if the transducers are positioned close to any
obstruction that distorts the uniformity of the flow profile.
Micronics Ltd accepts no responsibility or liability if product has not been installed in accordance
with the installation instructions applicable to the product.
Possible Air
Possible
sludge
Guide
rail
Uniform Flow Profile
Distorted Flow Profile
Flow
Flow
Valid transducer location
20 x Diameter
10 x Diameter

Micronics U1000MKII-HM User Manual
Issue X.X July 18
Page 8
5.1 Preparation
1. Before attaching the transducers, first ensure that the proposed location satisfies the distance
requirements shown in Figure 3 otherwise the resulting accuracy of the flow readings may be
affected. The unit is preconfigured for the application as follows :-
Instrument Type Heating or Chiller
Installation Flow or Return
Fluid Water or Water + 30% Ethylene Glycol
Flow and Return refer to the location of the Flow measurement relative to flow circuit.
Details of this configuration can be found in the Diagnostics menu. (See Section 9).
2. Prepare the pipe by degreasing it and removing any loose material or flaking paint in order to
obtain the best possible surface. A smooth contact between pipe surface and the face of the
transducers is an important factor in achieving a good ultrasound signal strength and therefore
maximum accuracy.
5.2 Sensor Separation
The sensors must be separated by the correct distance for the pipe size and type they will be used
on. The table below gives a guide to the typical separation code for a given pipe material and inside
diameter. If the wall thickness is significantly different from this value then the separation may need
to be one code higher or lower. The instrument displays the required separation after the pipe
internal diameter and material are entered.
Pipe ID
Pipe ID
Water
Glycol
PipeID
Pipe ID
Water
Glycol
mm
inches
S/Steel
S/Steel
mm
inches
M/Steel
M/Steel
20-22
0.79-0.87
A-3
A-3
21-22
0.83-0.87
C-3
C-3
26-29
1.02-1.14
B-2
B-2
27
1.06
D-2
E-3
34-36
1.34-1.42
C-2
C-4
35-36
1.38-1.42
C-4
C-4
37-40
1.46-1.57
B-3
D-4
41-44
1.61-1.73
C-3
F-3
52-58
2.05-2.29
B-2
D-3
52-54
2.05-2.13
C-4
C-4
59-64
2.32-2.52
A-3
F-3
62-65
2.44-2.56
F-3
F-3
72-79
2.83-3.11
B-3
E-5
76-79
2.99-3.11
E-5
G-4
86-92
3.39-3.62
C-3
B-4
88-94
3.46-3.70
B-4
B-4
99-105
3.90-4.13
D-3
C-4
95-101
3.74-3.98
D-3
C-4
125-131
4.92-5.16
F-3
E-4
122-128
4.80-5.04
F-3
E-4
152-158
5.98-6.22
E-5
G-4
150-156
5.90-6.14
E-5
G-4
Pipe ID
Pipe ID
Water
Glycol
Pipe ID
Pipe ID
Water
Glycol
mm
inches
PVC U
PVC U
mm
inches
Copper
Copper
22-23
0.87-0.90
C-3
C-3
20-39
0.79-1.54
B-1
B-1
27-28
1.06-1.10
D-2
C-3
20-39
0.79-1.54
B-1
B-1
36-37
1.42-1.45
C-4
C-4
20-39
0.79-1.54
B-1
B-1
43-45
1.69-1.77
C-3
B-4
20-39
0.79-1.54
B-1
A-2
56-59
2.20-2.32
E-3
E-3
47-53
1.85-2.09
C-1
C-1
67-69
2.64-2.71
E-4
D-5
61-67
2.40-2.64
A-3
A-3
78-81
3.07-3.19
D-2
C-3
68-74
2.68-2.91
C-2
B-3
95-101
3.74-3.97
D-3
C-4
96-102
3.78-4.02
B-4
B-4
109-115
4.29-4.53
E-3
D-4
117-123
4.61-4.84
E-3
D-4
122-128
4.80-5.04
F-3
E-4
146-152
5.75-5.98
D-5
D-5
143-149
5.63-5.87
F-4
E-5
157-162
6.18-6.34
G-4
F-5
Figure 4 Separation Table

Micronics U1000MKII-HM User Manual
Issue X.X July 18
Page 9
The diagram below shows how to adjust the separation of the sensors
Figure 5 Separation Setting
NOTE. When the sensors have been moved to the correct setting and the guide rail is
attached to the pipe REMOVE the sensor holding screws, which will allow the spring
loaded transducers to make contact with the pipe.

Micronics U1000MKII-HM User Manual
Issue X.X July 18
Page 10
5.3 Attaching the U1000MKII-HM to the pipe
After applying the Gel pads centrally on the sensors, follow the four steps shown in Figure 6 below
to attach the U1000MKII-HM to the pipe.
Figure 6 simple steps to attaching the U1000MKII-HM on the pipe
Note…The locking screws and washers should be kept in case it is necessary to change the
location of the guide rail and sensors. See the relocation section (section 10) for the procedure to do
this.
Remove the covers from the Gel pads
Ensure there are no air bubbles between
pad and sensor base
Check separation distance table on page 8 or
program unit before clamping guide rail to
pipe, using the supplied banding. Then
release and REMOVE sensor locking screws.
Connect sensors to the electronics
assembly before applying power.
Sensor leads can be connected either
way round.
Confirm the unit is working correctly before
attaching the electronic assembly onto
guide rail assembly.

Micronics U1000MKII-HM User Manual
Issue X.X July 18
Page 11
5.4 Adaptors For Small Pipes
Guide rails for small pipes are supplied with adaptors. The diagram below show how these are fitted
around the pipe. The top part of the pipe adaptor clips into the ends of the guide rail.
Figure 7 Pipe Adaptors
Less than 40mm outside diameter
40 to 60mm outside diameter
Greater than 60mm outside diameter

Micronics U1000MKII-HM User Manual
Issue X.X July 18
Page 12
5.5 Attaching The Temperature Sensors
The temperature sensors must be located at the input and output of the system that is being
monitored. The area of pipe where they are to be attached must be free of grease and any
insulating material. It is recommended that any coating on the pipe is removed so that the sensor
has the best possible thermal contact with the pipe.
The sockets on the enclosure are marked Hot and Cold. This defines the location of the
temperature sensors on installations where heat is being extracted from the system.
To ensure an accurate temperature differential the following procedure should be used.
1. Plug in the sensors and place them touching each other for 1 minute.
2. Enter the password controlled menu (See Section 8) and scroll to the calibration sub-menu.
3. Press the Enter key until the Zero Temp Offset screen is displayed.
4. Select Yes and press the Enter key to display the Attach Sensors screen.
5. Press the Enter key again and wait for instrument to return to the Zero Temp Offset screen.
The instrument can now be turned off and the installation of the temperature sensors completed.
The sensors have a cut out profile to locate them; they are then anchored using the supplied cable
ties. The cable ties should not be over tightened or the sensors may be damaged. If the sensors
are located under pipe lagging then ensure this does not put a strain on the sensor cables. Tie
down the sensor cables after the sensors have been installed.
The temperature sensors must be balanced before initial use, using the
procedure described above and used with the cable length supplied.
Extending or shortening the cables will negate the calibration of the sensors.

Micronics U1000MKII-HM User Manual
Issue X.X July 18
Page 13
5.6 U1000MKII-HM Interface Cables
The U1000MKII-HM interface cable supplied is a 6-core cable for power and pulse output
connections and a separate 4 core plug-in cable for the Modbus connections.
The un-insulated wire is the connection to the screen of the cable and should be earthed for full
immunity to electrical noise.
Figure 8 U1000MKII-HM instrument connections
5.7 Connecting The U1000MKII-HM To The Supply
The U1000MKII-HM will operate within the voltage range 12 - 24V ac/dc. The supply must have a
minimum rating of 7VA per instrument. Connect the external power supply to the Brown and Blue
wires of the six core cable.
For safety, connecting the U1000MKII to a power supply via a mains rated transformer is the
responsibility of the installer to conform to the regional voltage safety directives.
Power
Figure 8. U1000MKII-HM Interface Cable

Micronics U1000MKII-HM User Manual
Issue X.X July 18
Page 14
5.8 Pulse Output Connection
The isolated pulse output is provided by a SPNO/SPNC MOSFET relay which has a maximum load
current of 500mA and maximum load voltage of 48V AC. The relay also provides 2500V isolation,
between the sensor’s electronics and the outside world.
The pulse output is available at the White and Green wires. Electrically this is a volt, or potential free
contact, and when selected as a low flow alarm is configurable NO/NC.
5.9 Modbus Connections
A lead is provided for the Modbus connections that plugs into the electronics assembly near the
power cable entry. The Brown is the -ve bus wire and the Black is the +ve bus wire. Both White
wires go to ground.
Modbus Connector Cable Part - Binder 99-9210-00-04 (Front View)
For reliable operation of a Modbus network the cable type and installation must comply with
requirements in the Modbus specification document “MODBUS over Serial Line Specification &
Implementation guide V1.0”.
5.10Cable Screen
For full immunity to electrical interference the screen of the power/pulse output cable and modbus
cable should be connected to Earth.

Micronics U1000MKII-HM User Manual
Issue X.X July 18
Page 15
6 Powering Up For The First Time
Powering up for the first time will initiate the sequence shown in Figure 10:
Select the option required by pressing the keys
Figure 10 initial power up screens
Λ
V
V
Λ
Λ
V
Λ
V

Micronics U1000MKII-HM User Manual
Issue X.X July 18
Page 16
1. The Micronics start up screen is displayed for 5 seconds.
2. The user enters the pipe ID and selects the material (refer to section 6.1).
3. On pressing Enter in response to the Set Separation screen, the U1000MKII-HM then checks for
a valid signal.
4. If a valid signal is found, signal strength and flow rate are displayed. The signal strength should
be at least 40% for reliable operation. The direction of flow when powered up will be taken to be the
positive flow direction. The pulse output will relate to the flow in this direction. If the flow is reversed
then the flow rate will still be displayed but the activity indication will change from an asterisk to an
exclamation mark and no pulses will be generated.
If the flow value is displayed as “------“ this indicates that there is no usable signal from sensors.
The cause of this could be:
•Incorrect pipe data
•No Gel pad/grease on the sensor
•Sensor not in contact with the pipe
•Very poor pipe condition-surface/inside
•Air in the liquid/pipe
Please note:
There is little available data on the specific heat capacity (K factor) for water glycol
mixes and there is no practical method of determining the percentage of glycol in a
system or the type of glycol in use. The calculations are based on a Water/Ethylene
glycol mix of 30%.
In practical terms the results should not be considered more than an approximation
as:
The fluid speed of sound can vary between 1480ms and 1578ms
No temperature compensation curve is available for water/glycol mixes,
The percentage of Glycol can vary the specific heat capacity from 1.00 to 1.6 J/M3* K
The type of glycol added can change the specific heat capacity and fluid speed of
sound considerably.
The Factory enabled user set-up of the application relies on the installer to set the
correct operating parameters, a considerable variation in results can be obtained
from incorrectly set-up units.

Micronics U1000MKII-HM User Manual
Issue X.X July 18
Page 17
6.1 How To Enter The Pipe ID
Figure 11 shows the Enter Pipe ID screen after an initial power up.
Initially, the hundreds unit (050.0) will blink.
Press the
key to increment the hundreds digit (050.0) in the sequence 0, 1.
Press once to increment digit, to toggle between 0 and 1.
Press the
key to decrement the hundreds digit in the sequence 1, 0. Press
once to decrement digit, to toggle between 1 and 0.
Press the
key to move to the tens digit (050.0). The tens digit should now
blink.
Increment the tens digit in the sequence 0,1,2,3,4,5,6,7,8,9,0 using
the key. Press once to increment digit or hold down to scroll
through the numeric sequence. Decrement the tens digit in the
sequence 9,8,7,6,5,4,3,2,1,0,9 using the key. Press once to
increment digit to scroll through the numeric sequence.
Press the
key to move to the units digit (050.0). The units digit should now
blink. Increment or decrement the units digit in an identical manner
to the tens digit described above.
Press the
key to move to the decimal digit (050.0). The decimal digit should
now blink. Increment or decrement the decimal digit in an identical
manner to the tens digit described above.
Press the
Use
key to enter the Pipe ID numerical value, and move to the next
screen
and
keys to scroll through the pipe materials and then
press
To select the material and complete the setup
procedure.
If any of the parameters need to be changed from the default values, for example different units are
required, then the menu system must be activated via the password (see section 8).
V

>
>
>
Λ
V
Pipe material
Steel
V
Λ
Figure 11 Enter Pipe ID Screen (Metric)


Micronics U1000MKII-HM User Manual
Issue X.X July 18
Page 18
6.2 Pulse Output
Pulse output can be set up to operate in four modes: Volume, Frequency, Energy or Flow Alarm.
6.2.1 Volumetric Mode
In Volumetric mode, each pulse output represents a measured volume of 10 litres (default value). In
Volumetric mode, with the Vol per Pulse set to 1 and the pulse width set to 50ms, the maximum
number of pulses that can be output (without storage) is 1/(0.05*2) = 10 pulses per second. If the
flow rate in the pipe is such that it is greater than 10 pulses per second, increase the Vol per Pulse
to 10 litres, or reduce the Pulse Width value, to avoid creating a buffer of pulses when the flow
stops.
6.2.2 Frequency Mode
In Frequency mode, the pulse output frequency is proportional to the flow rate within a specified
frequency range of 1 –200Hz. The flow units on the frequency output are fixed as litres per
second.
The conversion factors from imperial units are:-
US gallons/minute multiply by 0.06309
US gallons/hour multiply by 0.00105
Imperial gallons/minute multiply by 0.07577
Imperial gallons/hour multiply by 0.001263
6.2.3 Energy Mode
When the Pulse Output is set to Energy, the kWh LED will be permanently on. Choose from
1,10,100kWh or 1MWh when in metric mode and 1,10,100kBTU or 1MBTU in imperial mode. Each
pulse represents an amount of energy e.g. 1kWh. The same limitation on maximum pulse rate
applies as detailed in the Volumetric Mode. Again a larger unit of energy per pulse or a smaller
pulse width may be required.
6.2.4 Flow Alarm –Low Flow or Signal Loss
It is possible to use the pulse output as a Low Flow Alarm or a Signal Loss Alarm.
For the High/Low Alarm the user can set a range between 0 and 9999 (no decimal places), in the
same units being used to measure flow. The default setting is normally open, but the user can
select between N/O and N/C. There is a 2.5% hysteresis on the switching of the output. Once
turned on the flow rate must rise by 2.5% more than the set value to turn it on/off again.
If the flow reading (Signal) is lost, as indicated by the flow rate being displayed as “-----“, the alarm
will be triggered. The Pulse LED will indicate the state of the alarm. The default setting is normally
open, but the user can select between N/O and N/C.
The Pulse LED will be on if the alarm is set.

Micronics U1000MKII-HM User Manual
Issue X.X July 18
Page 19
6.3 Modbus (if fitted)
The Modbus RTU interface is configured via the Modbus sub menu in the password controlled
menu.
The data rate can be selected in the range 1200 to 38400 baud.
The address can be set in the range 1 to 126.
Polling Rate 1000ms (1sec). Time out after 5 seconds.
The instrument responds to the “read holding registers” request (CMD 03).
If the flow reading is invalid then the flow value will be zero.
If a temperature sensor goes out of range then the value will go to -11.
Both of these faults will set the relevant status bit.The following registers are available.
Modbus
Register
Register
Offset
Type
Typical
Contents
Meaning
Notes
n/a
n/a
Byte
0x01
Instrument Address
n/a
n/a
Byte
0x03
Instrument Command
n/a
n/a
Byte
0x40
Number of bytes to read
40001
0
Int-16
0x00
Device ID
0xAC Energy Meter
0xac
40002
1
Int-16
0x00
Status
0x0000 OK
Not[0x0000] Fault
0x00
40003
2
Int-16
0x00
System Type
0x04 Heating system
0x0C Chiller system
0x04
40004
3
Int-16
0x00
Serial Identifier
0x01
40005
4
Int-16
0x23
0x45
40006
5
Int-16
0x60
0x00
40007
6
iee754
0x40
Measured Velocity
Units in m/s
0x1f
40008
7
0x67
0xd3
40009
8
iee754
0x41
Measured Flow
Units in m3/hr for
Metric
Units in US Gal/m
for Imperial
0x8c
40010
9
0xd8
0xb0
40011
10
iee754
0x42
Calculated Power
Units in kW for
Metric
Units in BTU/s for
Imperial
0x1c
40012
11
0x2e
0x34
40013
12
iee754
0x44
Calculated Energy
Units in kWh for
Metric
Units in kBTU for
Imperial
0x93
40014
13
0xc6
0xe8

Micronics U1000MKII-HM User Manual
Issue X.X July 18
Page 20
On a unit set to Imperial the temperature is in °F, Power is in BTUs and flow in US Gallons.
Figure 12 Modbus registers
40015
14
iee754
0x41
Measured Temperature (Hot)
Units in Degrees Celsius for
Metric Units in Degrees
Fahrenheit for Imperial
0x98
40016
15
0x00
0x00
40017
16
iee754
0x41
Measured Temperature (Cold)
Units in Degrees Celsius for
Metric Units in Degrees
Fahrenheit for Imperial
0x88
40018
17
0x00
0x00
40019
18
iee754
0x40
Measured Temperature
(Difference)
Units in Degrees Celsius for
Metric Units in Degrees
Fahrenheit for Imperial
0x00
40020
19
0x00
0x00
40021
20
iee754
0x60
Measured Total
Units in m3 for Metric
Units in US Gal for Imperial
0xef
40022
21
0x3c
0x1c
40023
22
Int-16
0x00
Instrument Units
0x00 Metric
0x01 Imperial
0x00
40024
23
Int-16
0x00
Instrument Gain
Gain in dB
0x01
40025
24
Int-16
0x00
Instrument SNR
SNR in dB
0x0a
40026
25
Int-16
0x00
Instrument Signal
Signal in %
0x62
40027
26
iee754
0x42
Measured Delta-Time
Difference
Diagnostic Data
Units in nanoseconds
0xc9
40028
27
0xff
0x7d
40029
28
iee754
0x42
Instrument ETA
Diagnostic Data
Units in nanoseconds
0xa8
40030
29
0x8b
0xf5
40031
30
iee754
0x42
Instrument ATA
Diagnostic Data
Units in nanoseconds
0xc8
40032
31
0x00
0x00
n/a
n/a
Int-16
0xed
CRC-16
0x98