Installation, Operation & Maintenance Manual
IP2040/IM, Rev. AA
May 2007 |
|
|
| MSP900SH |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Hmax
Hmax
It is important to note that the bottom reference of the transmitter should be related to the centre of the invert of the primary device, NOT the distance to the channel bottom directly below the transmitter.
Transmitter bottom
Flow
Channel
invertPrimary element (eg. Flume, weir) invert
In addition to the above, when setting the bottom reference on a ‘V’ notch weir it is important that the true invert of the weir is taken and not the meniscus liquid level, which may be 3 to 4mm above the true invert.
True invert
Meniscus
Transmitter bottom reference
•The liquid surface at the point of measurement must have a stable, smooth surface and uniform approach velocity. It must not be affected by baffles, foam, hydraulic jumps or any other object likely to cause flow disruption.
•The primary element should be free from any situation where it is likely to ‘drown’ (refer to relevant standard for further information)
•The MSP900SH transmitter has integral temperature compensation and must be protected at all times from direct sunlight and any radiated heat.
For maximum accuracy and stability of level measurement reading the transmitter should always be shrouded to prevent the incidence of direct sunlight.
If the flow structure permits, mount the transmitter within the flow channel or chamber.
Page 7