Net Safety SAFEGUARD CONTROLLER, Руководство пользователя

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11
SafeGuard Controller User Manual
MAN-0115 Rev 0
If Modbus 32 BIT is selected, a Byte Order entry appears at the bottom of the menu.
This determines WORD and BYTE alignment of data at the remote Modbus transmitter
when sending its 4 byte IEEE Floating Point values. With the pointer on this entry, the
EDIT key toggles between the 4 possible modes. Min / Max Raw values are not used in
this mode.
Note: Each Data From : item has a matching default Min/Max counts value of 20% to
100% with ± 5% over/under range applied. If the default value is incorrect for the input
device it should be edited.
2.2.4b MARKER MENUS
Some transmitters or monitoring devices providing SafeGuard Controller inputs also
indicate special modes of operation, such as
Calibration, Maintenance or Fault, by
transmitting a special <4mA or negative “Marker” value. The SafeGuard Controller
offers channel Marker menus for detecting and indicating such events (see Figure 2.5).
While active, the SafeGuard Controller displays a 6-digit ASCII message to indicate the
special event and if equipped with SG10-0167 4-20mA output option, the SafeGuard
Controller also transmits the same <4mA value.
•
Marker Enabled turns the marker feature ON and OFF
•
The negative Marker value is entered into the Marker % field as a negative percent
of full scale. For example, -15.62% of full scale detects a marker value of 1.5mA
(1.5mA is -15.62% of full scale when 4-20mA is the range).
•
It should be noted that for Net Safety Flame Detectors the current output for a
visual integrity fault is 2.0 mA this corresponds to a Marker % of -12.5%. For
Net Safety Gas Sensor Fault Condition, the current output is 2.5 mA which
would correspond to a Marker % of approximately -9.4 %.
•
The Mark As menu allows user entry of the 6-digit ASCII message to be displayed
when the marker is detected.
Figure 2.5
2.2.4c SENSOR LIFE DETECTION (- this feature is not used at this time)
Sensor Life should only be activated when the Marker event is Calibration and when a
sensor life value is transmitted after each calibration. For Sensor Life to record properly
the monitor must perform as follows: After the Calibration Marker interval, 4.0mA
transmits for 10 seconds to indicate its calibration mode is complete. The monitor then
transmits between 4.0mA and 5.0mA for five seconds depending on remaining sensor life
where 4.0mA = 0% and 5.0mA = 100% remaining sensor life. The SafeGuard Controller