5
Operation and Maintenance
5.1
Safety messages
Instructions and procedures in this section may require special precautions to ensure the
safety of the personnel performing the operations. Information that potentially raises
safety issues is indicated by a warning symbol ( ). Refer to the following safety messages
before performing an operation preceded by this symbol.
WARNING
Failure to follow these installation guidelines could result in death or serious injury.
Ensure only qualified personnel perform the installation.
Explosions could result in death or serious injury.
Before connecting a handheld communicator in an explosive atmosphere, ensure the
instruments are installed in accordance with intrinsically safe or non-incendive field wiring
practices. Verify that the operating environment of the device is consistent with the
appropriate hazardous locations certifications.
Electrical shock could cause death or serious injury.
Use extreme caution when making contact with the leads and terminals. Device must be
installed to ensure a minimum antenna separation distance of 8 in. (20 cm) from all
persons.
5.2
Operation
The Rosemount 708 Acoustic Wireless Transmitter measures ultrasonic acoustic energy
and waveguide temperature. The acoustic level is reported in 'counts,' which are a relative
indication of the magnitude. The sensor used in the Rosemount 708 Transmitter is
sensitive to a broad range of frequencies to work in many different applications. The
acoustic measurement or “count” in the transmitter is an average of the broad range of
frequencies. No additional signal processing is performed to isolate specific frequencies.
This count information is used to determine the state of a steam trap, pressure relief valve,
or other mechanical system. The device works similarly to a discrete device, looking for a
large change in noise level occurs during a leak or release. In the case of steam traps,
SteamLogic
™
software calculates the steam trap state based on the acoustic and
temperature information published by the Rosemount 708 Transmitter. See SteamLogic
for further information.
When monitoring other equipment, the Rosemount 708 Transmitter may be configured
with alerts to detect and communicate changes in the state of the system being
monitored.
Reference Manual
Operation and Maintenance
00809-0100-4708
June 2022
Rosemount 708 Wireless Acoustic Transmitter Reference Manual
27
