Troubleshooting And Maintenance; Power-Up Behavior; Hart Diagnostic Messages; Critical Diagnostics - Honeywell SLG 700 User Manual

6 Troubleshooting and Maintenance

6.1 Power-Up Behavior

On power-up the loop current is set to 21.5 mA and HART digital communication by default. Start
up time is 45 seconds from when the device is powered up.
Distance to Product and Distance to Interface (if applicable) are set to zero and the loop current to
21.5 mA until a valid level is detected by the transmitter. In case of critical faults the device sets
the loop current to burnout level as programmed (Low scale <3.6 mA or High scale 21.5 mA).

6.2 HART Diagnostic Messages

6.2.1

Critical diagnostics

Table 15 critical HART diagnostic messages, also called alarms.
Name (DTM/DD)
Reset required
Measurement Failure
Revision 5

Table 15 - HART Critical Diagnostic Messages

Description (Cause)
This flag is set when sensor
parameters configuration is changed
that requires a device reset.
This is a roll-up status bit that is set
when any of the following critical status
conditions are present.
If Device variable selected as Primary
Variable (PV) is not applicable for
configured measured product.
 PV selected is any of Volume
device variables and the value is
either infinite or not a valid number.
 PV Selected is derived from
measured level which is either
infinite or not a valid number.
 Primary Variable bad
SLG 700 Series HART Option User's Manual
Resolution (Steps to take)
Power cycle the device to perform a
hard reset of all transmitter
electronics. New reflection models
and minimum blocking distance limits
will be calculated while the transmitter
is starting up.
If the non-critical Device Variable Not
Supported status is set, check if the
device variable selected as Primary
Variable is applicable for the
configured measured product type.
See page 19.
If the non-critical Volume Calculation
Failure status is set, check if Volume
Calculation Type is configured as
"Strapping table", check the Strapping
table entries for valid data. If Volume
calculation type is selected as "Ideal
Tank Shape" check the tank
dimensions configured are valid and
correct.
If the non-critical Linearization Table
Error Status is set, check the
Linearization table for valid entries
corresponding to Measured and
Adjusted level values.
If the non-critical PV bad is set, check
the distance to interface or distance to
product used to derive the Primary
variable is valid or not. The reason
may be due to loss of surface or
Interface peak.
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