Endress+Hauser HART Proline t-mass I 300, Руководство по эксплуатации

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Proline t-mass I 300 HART Technical data
Hauser 167
Light gases (hydrogen, helium)
• The reliable measurement of light gases can be difficult due to their very high thermal
conductivity. Depending on the application, the flow rates of light gases are often
particularly slow and the flow profiles are not sufficiently developed. The flows are
frequently in the laminar flow range, while turbulent flow would actually be needed for
optimum measurement.
• Despite loss of accuracy and linearity in applications with light gases and low flow rates,
the device measures with a good degree of repeatability and is therefore suitable for
monitoring flow conditions (e.g. leak detection).
• The recommended inlet runs must be doubled for light gases.→  21
Operable flow range • 200:1 with factory calibration
• Up to 1000:1 with application-specific adjustment
Input signal External values
The measuring device provides interfaces which allow values measured externally
→  167 to be transmitted to the measuring device:
• Analog inputs 4-20 mA
• Digital inputs
Pressure values can be transmitted as absolute or gauge pressure. For gauge pressure, the
atmospheric pressure must be known or specified by the customer.
HART protocol
The measured values are written from the automation system to the measuring device via
the HART protocol. The pressure transmitter must support the following protocol-specific
functions:
• HART protocol
• Burst mode
Current input
The measured values are written from the automation system to the measuring device via
the current input →  167.
Current input 0/4 to 20 mA
Current input 0/4 to 20 mA (active/passive)
Current span • 4 to 20 mA (active)
• 0/4 to 20 mA (passive)
Resolution 1 µA
Voltage drop Typically: 0.6 to 2 V for 3.6 to 22 mA (passive)
Maximum input voltage ≤ 30 V (passive)
Open-circuit voltage ≤ 28.8 V (active)
Possible input variables • Pressure
• Temperature
• Mol-% (gas analyzer)
• External reference flow rate (in-situ adjustment)
Status input
Maximum input values • DC –3 to 30 V
• If status input is active (ON): R
i
>3 kΩ
Response time Configurable: 5 to 200 ms