10
SafeGuard Controller User Manual
MAN-0115 Rev 0
numbers define the location of the variable representing the input value and must
be obtained from the manufacturer of the Modbus RTU device.
EDIT
toggles the
Data From
: entry between
Analog,
Analog with Local Cal
and Modbus
RTU (signed, unsigned & floating point)
.
Analog Input
should be selected when the channel’s input comes from a transmitter or
monitoring device with a
calibrated
output such as 4-20mA.
Sensor Direct
is identical to
Analog Input with Local Cal
and both activate the SafeGuard Controller’s
Cal Mode
features. Problems may arise if calibrations are performed in two places upon the same
signal so Cal Mode menus are only visible when
Sensor Direct or Analog Input with
Local Cal
is selected. These applications would require the SafeGuard Controller to be
used as the calibration point; when calibration transmitter and sensor configuration at the
SafeGuard Controller, select
Analog Input with Local Cal.
Note that gas sensors are not
connected directly to the SafeGuard Controller at this time, hence
Sensor Direct
is not
used.
Figure 2.4
2.2.4a MIN / MAX RAW COUNTS MENUS
The Min Raw and Max Raw counts entries included in Input Data From: menus define
the range of input counts that provide
Measurement
Range
read-out values described in
section 2.2.6b. This menu entry is determined by the A/D converter resolution of the
channel’s input. For example, if the input is a 10 bit Modbus® device with zero at 200
counts and 100% at 1000 counts, then this menu’s MIN should be set at 200 and MAX at
1000. If communicating with the SafeGuard Controller’s optional 12 bit Analog Input
PCB the MIN should be 800 and the MAX 4000.
If the input device’s resolution is unknown, the live counts variable on the bottom of the
screen displays actual raw A/D counts currently being read by this channel. This reading
may be used to test the input device for what A/D counts are provided for zero and 100%
if these values are unknown. Forcing the input device to read zero should provide the
A/D counts value needed to make this channel’s display also read zero. Likewise,
forcing the input device to read 100% should provide the A/D counts value needed to
make the SafeGuard channel’s display also read 100%.
*
Direct Gas Sensor inputs
are not used at this time
*
*
The Wireless Option and features
are not used at this time
*
*
*
*
*
