Yokogawa EJX930A - Manual (Page 72)

<4. Diagnostics>
4-22
IM 01C25R02-01E
Amplifier
Temperature
Capsule
Temperature
Amp temp
Cap temp
Flg temp Coef
Flg temp
Execution HTM
CT+(CT-AT) x Cf
Calculation of
Flg temp
Cap temp
Flg temp
Diag Error
Display on LCD
Response Code
(Device Status)
Status group 9
Contact Output
(Digital Output)
4-20mA DC
(Analog Output)
Amp temp
Sensor signals Sensor Process Value
calculation
Alarm Masking
Result of HTM detection
HTM alarm
Result of HTM detection
DO Config
HTM alarm
HTM alarm Diag Output
Option
F0412.ai
Figure 4.9 Functional Block Diagram of Heat Trace Monitoring (HTM)
4.2.3.2 Out of Temperature Measurement
Range
When the flange temperature is out of
measurement range, the alarm or alert is
generated. For the detail of alarm and alert setting,
refer to subsection 4.2.2.5.
The measurement range is set to
Flg temp Hi Alert
Val and Flg temp Lo Alert Val, which values can
be specified within -50 to 130 deg C.
Flgtemp Flg temp
F0413.ai
Time Time
An alarm is generated.
An alarm is generated.
Flg temp Hi Alert
Flg temp Lo Alert
4.2.3.3 Parameter Lists for Heat Trace Monitoring
# Parameter name Default value Explanation
1 Diag Error 0x0000 The results detected by ILBD or Heat trace monitoring are stored into this
parameter. Also the condition abnormality in the diagnostic process is
stored as an error.
2 Diag Option 0x08FC The masking in this parameter enable to display each error message and
the status to the output signal or LCD.
The error assigned to each bit is corresponding to that of Diag Error.
Writable only when Diag Mode is "Stop".
3 Diag Out Option Off The error status can be output by 4-20 mA analog signal.
There are following three output modes; Off, Burnout, or Fall back.
4 Diag Fixed Out Val 21.6mA Parameter for "Fall back" function in the Diag Out option.
The output value in 4-20 mA analog signal is specified when an alarm is
generated.
The value must be entered within 3.8 to 21.6 mA.
5 Cap temp Measured capsule temperature value
6 Amp temp Measured Amplifier temperature value
7 Flg temp (Note) Calculated flange temperature value
8 Flg temp Coef 0 Coefficient to calculate flange temperature (Cf: Rt
1
/Rt
2
)
Rt
1
: Thermal resistance between the flange and capsule.
Rt
2
: Thermal resistance between the cupsule and amplifier.
9 Flg temp Hi Alarm Val 120 deg C Upper limit of Flg temp
10 Flg temp Lo Alarm Val -40 deg C Lower limit of Flg temp
11 DO Select Off See subsection 3.3.12 Status Output
12 DO Signal type ON WHEN
AL DETECT
See subsection 3.3.12 Status Output
13 Digital Output Off See subsection 3.3.12 Status Output
Note: The Flg temp Coef is 0 at the shipment so that the Flg temp outputs the same value as that of Cap temp.