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6.0 SAFETY, MAINTENANCE, AND TROUBLESHOOTING
The AT100 will operate normally without the need for periodic maintenance or inspection. If the transmitter
meets or exceeds the requirements of the application, the transmitter can be expected to provide reliable level
indication for a minimum of 10 years.
If the AT100 transmitter is being used as part of a Safety Implemented System (SIS), periodic testing will be
required to proof the transmitter and detect any potential failure which is defined as Dangerous Undetectable in
normal operation. Proof testing must be performed at regular intervals (2 years) and the results of this testing must
be documented. Should the transmitter exhibit a fault during normal operation, it will be necessary to perform the
proof testing regardless of schedule. As part of the testing documentation, all parameters included in the menu
structure of the transmitter (see page 8) as well as the configuration of the module jumpers (see page 6) must be
recorded. An AT100 can be equipped to provide a level indication from two floats as well as a temperature
indication from an RTD installed in the sensor tube. The transmitter is only capable of supplying (1) 4-20mA output
based on one of the two possible levels. If a transmitter is equipped with more than one float and/or a temperature
indication, only the process variable selected by the PV= menu option will be considered as a safety function as this
selected variable will be the basis for the 4-20mA output. The AT100 transmitter may only be used in a safety-
related system when the mode of that system is low demand. As a device, the AT100 transmitter will be used to
provide a level measurement to prevent overfill and dry run of a vessel.
If a transmitter fails an inspection or assistance is required for inspection or troubleshooting, contact the
Service Department at K-TEK Corporation via e-mail at service@ktekcorp.com. The Service Department will answer
questions, provide additional assistance, and issue Return Authorization Numbers for equipment in need of repair.
CAUTION: In the event a magnetostrictive transmitter has suffered a failure in any component which is exposed to the process,
any other magnetostrictive transmitter installed in the same or similar process should be inspected for the same failure regardless
of its maintenance schedule. These Common Cause Failures include: 1) float collapse due to over pressure, 2) probe or float
corrosion due to material incompatibility, 3) deformation of the sensor tube due to process agitation.
Notes on usage in Safety Instrumented Systems:
1)
The AT100 performs internal diagnostics at a maximum interval of 15 minutes.
2)
The AT100 will provide annunciation of a diagnostic failure in less than 15 minutes of the occurrence.
3)
The failure of any internal diagnostics will result in notification of the fault by setting of diagnostic bits in HART protocol
output.
4)
All AT100 FMEDA analysis is based on using a safety accuracy of 2%.
5)
The internal diagnostics are designed to achieve a Safe Failure Fraction of 90% minimum.
6)
The target average probability of failure on demand is less than 1.5 x 10
7)
AT200 transmitters may only be used in a SIS when:
a) Transmitters are fitted with a 4-20 mA output HART Protocol /M4A or /M4B or /M4B or /M4AS or /M4BS Electronic Module
b) Modules must be marked as follows: AT_H_01_S003_090209 or AT_H_TS_01_S003_090209
6.1 Personnel Qualifications
Safety Inspection, Maintenance and Troubleshooting should only be performed by qualified personnel.
These qualifications include a knowledge of the information in this instruction manual, knowledge of the product and
its operating principles, knowledge of the application in which the transmitter is being applied, and general
experience as an Instrument Technician.
6.2 Required Tools
The following tools may be required to perform inspection, maintenance or troubleshooting of the AT100
transmitter.
- Crescent Wrench
- Screwdrivers
- Hex Key Wrenches
- Digital Multi-meter
- Tape Measure
- Portable Oscilloscope (optional)
- Oscilloscope Connector (purchased from K-TEK) or three pieces 26awg solid core wire (6in/150mm)
AT100-0200-1 Rev L (10-2010) DCN0528
-3
.
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