HF scientific MicroTOL Online Turbidimeter old series- 0-1000 NTU User Manual
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MICRO TOL (12/04)
Rev. 2.7
26
8.0 Troubleshooting & Maintenance
8.1 Micro TOL Fault Detection
The Micro TOL performs continuous diagnostic monitoring. In the Micro TOL there are
three levels of fault detection; warnings, errors and failures.
A warning indicates that there is a system problem that does not interfere with the
operation of the instrument and can be corrected by the operator. These warnings consist
of 4-20 mA loop open (MA) if equipped, and desiccant replacement required (DESC). At
this level of fault there is only a screen display indicating the problem.
An error indicates a failure or a problem that does interfere with the operation but can be
corrected by the operator. These errors consist of lamp out (LAMP) & no flow (FLOW)
(if equipped with the flow switch). If any of these conditions occurs, both alarm relays (if
equipped) will be activated and the 4-20 mA output will be held at 2 mA (if equipped). If
any of these errors occur the instrument will still display readings, however the accuracy
is not known and the instruments readings should not be trusted.
A failure is a system fault. This is NOT a problem that the operator can correct, and the
unit must be returned to the factory for service. These failures consist of failures in the
CPU, A/D, EEPROM or other devices internal to the instrument (FAIL). If a failure
occurs, the instrument will not operate. At best it will display the word FAIL on the lower
row and both alarm relays (if used) will be activated and the 4-20 mA output will be held
at 2 mA (if used).
If any fault conditions occur, the message indicating the fault will be shown on the lower
row of the display.
8.2 System FAIL Message
Normally, this condition indicates that the instrument will require servicing. Contact
either the HF scientific, inc. Technical Service Department or the HF scientific, inc.
Customer Service Department.
HF scientific, inc.
3170 Metro Parkway
Fort Myers, Florida 33916-7597
Phone: (239) 337-2116
Fax: (239) 332-7643
Email: