Panametrics PanaFlow XMT1000, User Manual, Page: 12 / 80

1.4.4 Local mounting
The XMT1000 accuracy is affected by the flowcell
location in the process piping and on the orientation
of the transducers. Thus, in addition to accessibility
for maintenance, adhere to the following installation
guidelines:
• Locate the flowcell so that there are at least 10 pipe
diameters of straight, undisturbed flow upstream
and 5 pipe diameters of straight, undisturbed flow
downstream from the measurement point (see
figure 4 ). Undisturbed flow means avoiding sources
of turbulence in the fluid (e.g., valves, flanges,
expansions, elbows, etc.), avoiding swirl, and
avoiding cavitation.
• Locate the transducers on a common axial plane
along the pipe. Also, locate them on the side of the
pipe instead of on the top or the bottom, because
the top of the pipe tends to accumulate gas and
the bottom tends to accumulate sediment. Either
condition will cause unwanted attenuation of the
ultrasonic signals. There is no similar restriction with
vertical pipes, as long as the fluid flow is upward to
prevent free falling of the fluid or a less than full pipe
(see figure 5) .
CAUTION!
Do not place thermal insulation on or
around the transducers, the junction boxes,
or the meter electronics. The transducer
and junction box act as a heat sink that
protects the transducer from high and
low temperatures.
1.4.5 Remote mounting
The standard XMT1000 enclosure is a powder-coated,
aluminum, IP67 explosion-proof enclosure. Typically,
the enclosure is mounted as close as possible to
the transducers. When choosing a site for a remote-
mount installation, which is recommended for process
temperatures exceeding 150°C, make sure the location
permits easy access to the enclosure for programming,
maintenance and service.
Attention European customers!
For compliance with the European Union’s
low voltage directive, this unit requires an
external power disconnect device such as
a switch or circuit breaker. The disconnect
device must be marked as such, clearly
visible, directly accessible, and located
within 1.8 m (6 ft) of the unit.
1.4.6 Cable lengths
Locate the XMT1000 as close as possible to the transducers.
The maximum distance from the transducers for remote
mounting of the XMT1000 is 1000 ft (300 m) using RG-62
coaxial cable or equivalent. If longer distances are required,
consult the factory for assistance.
1.4.7 Transducer cables
When installing the transducer cables, always observe
established standard practices for the installation of
electrical cables. Do not route transducer cables alongside
high amperage AC power lines or any other cables that could
cause electrical interference. Also, protect the transducer
cables and connections from the weather and corrosive
atmospheres, and be sure to follow the manufacturer’s
installation guidelines if cable glands are provided.
Flow direction
10D 5D
Figure 4: Minimum straight run pipe requirements
BAD
Vertical
flowcell
GOOD
Flow directio
n
Flow directio
n
Flow direction
GOOD
BAD
Horizontal
flowcell
Figure 5: Good and bad flowcell/transducer orientations
4