Net Safety SAFEGUARD CONTROLLER, Руководство пользователя

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13
SafeGuard Controller User Manual
MAN-0115 Rev 0
2.2.6b INPUT MEASUREMENT RANGE
The
ZERO / SPAN
entries allow configuration of the measurement range displayed by
the channel. Measurement Range works along with A/D Counts menus, described in
section 2.2.4a, to define the range of the input signal’s engineering units. For example, if
a channel’s input is 4-20mA from a transmitter monitoring 0 to 10ppm H2S, then the
Zero value should equal 0.000 and the Span value equal 10.00. The six ASCII
engineering units previously entered are automatically displayed at the top of each menu
as a reminder. Four digits must appear in this entry so trailing 0’s may appear here that
are not displayed on other data screens.
2.2.6c DECIMAL POINT RESOLUTION
Resolution of displayed channel values is configured in this menu by setting the number
digits trailing the decimal point. Values are limited to a maximum of four digits, and a
polarity sign. An auto-ranging feature displays the highest resolution allowed by this
menu’s decimal point entry. For example, if three decimal points are entered, and the
range is 0 to 100ppm, the reading will be
0.000 at 0ppm and 100.0 at 100ppm. However,
this may be undesirable due to the high resolution at zero unless the detector’s output is
extremely stable. If decimal points are limited to one, the 0ppm reading becomes
0.0 and
the 100ppm reading remains 100.0 . Resolution may be limited further by setting decimal
points to 0. In the above example, this would cause 0ppm to display 0 and 100ppm to
display 100 .
2.2.6d TURNING OFF UNUSED CHANNELS
The
Channel On?
entry determines if this channel is to be utilized. Turning it off will
cause the SafeGuard Controller to never process inputs applied to this channel and no
alarms will be tripped or data displayed. Inactive channels have a line drawn through
them on the Setup screen as indicated by channels 15 & 16 in Figure 2.0. If less than 9
channels are to be activated, the SafeGuard Controller may be set for 8 channel mode,
deactivating channels 9-16. This is done in the System Setup menu described in section
2.3. The SafeGuard Controller will only allow 15 channels to be turned off. At least one
channel must remain on.
2.2.6e COPY DATA TO?
This menu simplifies the Setup procedure by allowing similar channels to be copied from
one to another. For example, if all channels are identical except for the
Measurement
Name entry, channel 1 could be configured and copied to channels 2 – 16. Only
Measurement Name then must be configured on channels 2 – 16. Use EDIT to increment
channel numbers and UP/DN to point to Copy Now? Press EDIT once more to copy.