Endress+Hauser Proline Promass F 300, Руководство по эксплуатации

Страница: 241 / 264

Proline Promass F 300 EtherNet/IP Technical data
241
If the sensor is to be purged with gas (gas detection), it should be equipped with purge
connections.
Do not open the purge connections unless the containment can be filled immediately
with a dry, inert gas. Use only low pressure to purge. Maximum pressure:
5 bar (72.5 psi).
In case of a tube failure, the pressure level inside the secondary containment will rise
according to the operating process pressure. If the user judges that the secondary
containment pressure rating/burst pressure does not provide an adequate safety margin,
the device can be fitted with a rupture disk. This prevents excessively high pressure from
forming inside the secondary containment. Therefore, the use of a rupture disk is strongly
recommended in applications involving high gas pressures, and particularly in applications
in which the process pressure is greater than 2/3 of the secondary containment burst
pressure.
For information on the dimensions: see the "Mechanical construction" section of the
"Technical Information" document
Rupture disk To increase the level of safety, a device version with a rupture disk with a trigger pressure
of 10 to 15 bar (145 to 217.5 psi)can be used (order code for "Sensor option", option CA
"rupture disk").
Rupture disks cannot be combined with the separately available heating jacket .
Special mounting instructions: →  28
For information on the dimensions: see the "Mechanical construction" section
Flow limit Select the nominal diameter by optimizing between the required flow range and
permissible pressure loss.
For an overview of the full scale values for the measuring range, see the "Measuring
range" section →  223
• The minimum recommended full scale value is approx. 1/20 of the maximum full scale
value
• In most applications, 20 to 50 % of the maximum full scale value can be considered ideal
• A low full scale value must be selected for abrasive media (such as liquids with entrained
solids): flow velocity < 1 m/s (< 3 ft/s).
• For gas measurement the following rules apply:
– The flow velocity in the measuring tubes should not exceed half the sound velocity
(0.5 Mach).
– The maximum mass flow depends on the density of the gas: formula →  223
To calculate the flow limit, use the Applicator sizing tool →  220
Pressure loss To calculate the pressure loss, use the Applicator sizing tool →  220
Promass F with reduced pressure loss: order code for "Sensor option", option CE "reduced
pressure loss"
System pressure →  26