ABB SensyTemp TSA101, Safety Instructions

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Safety function
8 SensyTemp TSP SM/TSP/SIL-EN
6 Safety function
6.1 Overview
The temperature sensors in the SensyTemp TSP series can be used in applications according
to safety standards with the TTH300 transmitter or without a transmitter. Use the “CS” option
when ordering to select the safety version according to SIL Level 2.
6.2 SensyTemp TSP temperature sensors with TTH300 transmitter
The SensyTemp temperature sensor with built-in TTH300 transmitter generates a linear
temperature signal proportional to the connected temperature sensor (4 … 20 mA). All safety
functions refer strictly to the analog output signal.
The entire valid range for the output signal must be configured between min. 3.8 mA and max.
20.5 mA (factory setting).
Warning!
In safety mode, HART communication occurs only when write protection is activated. The
HART master must comply with the safety requirements of the customer application.
Alarm behavior and current output
When a critical error is detected, the configured alarm current is generated and fed to a
downstream logics unit, e.g., a DCS, which checks for overshoots of a defined maximum value.
There are two selectable modes for the alarm current:
• HIGH ALARM (high alarm, max. alarm current); this is the factory setting
• LOW ALARM (low alarm, min. alarm current)
The low alarm current can be configured in a range from 3.5 to 4.0 mA. The factory setting is
3.6 mA.
The high alarm current can be configured in a range from 20.0 to 23.6 mA. The factory setting is
22 mA.
In the following cases, a detected error is displayed independently of the configured alarm
current within the low alarm range:
• Runtime errors
• Memory error (non-volatile data, RAM, ROM)
After switching on or restarting the transmitter electronic unit, the minimum low alarm time
(LOW-alarm, startup time) is 10 to 15 seconds.
Warning!
To ensure accurate error monitoring, the following conditions must be fulfilled:
• The low alarm must be configured to a value of
≤
3.6 mA.
• The high alarm must be configured to a value of
≥
21 mA.
•
The DCS must identify the configured high and low alarms as malfunctions, and the alarm
must be configured according to the desired setup.
Warning!
To ensure the current output is functioning properly, the terminal on the standard device must
be between 11 V … 42 V DC (Ex version: 11 V … 30 V DC).