Micronics U1000MKII-FM, User Manual

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U1000MKII User Manual Micronics
Page 46 Issue 3.1 July 19
6.2 Default values
The settings will be configured at the factory for metric units. The following table lists the metric and
imperial default values.
Parameter Default Value
Metric Imperial
Dimensions mm inches
Flow Units l/min USgal/min
Pipe size (ID) 1" to 4" and 1" to 6" pipes: 50 mm
4" to 6" pipes: 127 mm 1" to 4" and 1" to 6" pipes: 1.969 in
4" to 6" pipes: 5.000 in
Pulse Output Off Off
Energy per Pulse
(U1000MkII-HM only)
1kW 1kBTU
Volume per Pulse 10 litres 2.642 US gallons
Pulse Width 50 ms 50 ms
Damping 20 seconds 20 seconds
Calibration Factor 1.000 1.000
Zero Cut-off 0.02 m/s 0.07 ft/s
Zero Offset 0.000 m/s 0.000 ft/s
6.3 Limitations with Water-Glycol Mixtures
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 flow 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.
6.4 Positioning
For accurate measurements, the U1000MKII-FM must be installed at a position where the fluid flows
uniformly. Flow profile distortions can result from upstream disturbance such as bends, tees, valves,
pumps and other similar obstructions. To ensure a uniform flow profile, the unit must be mounted
away from any cause of flow disturbance.
As a guide, we suggest this is best achieved by ensuring there is a straight length of pipe upstream
of the transducers of at least 10 times the pipe diameter, and 5 times the pipe diameter on the
downstream side, as shown in Figure 3, but this may vary. Flow Measurements can be made on