Omega SP-006, User Manual

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6.2.1.3.5 Sensor Range / Type
The lower 4-bits of the Range byte are
read-only
.
Sensor Type Sensor Input Type (Range) Measurement Type
0x00 Reserved
0x01 Reserved
0x02 100 kPa (15 psi) 0x28 Pressure (Kilo Pascal)
0x03 200 kPa (30 psi) 0x28 Pressure (Kilo Pascal)
0x04 350 kPa (50 psi) 0x28 Pressure (Kilo Pascal)
0x05 700 kPa (100 psi) 0x28 Pressure (Kilo Pascal)
0x06 Reserved
0x07 Reserved
0x08 +/- 100 kPa (+/- 15 psi) 0x28 Pressure (Kilo Pascal)
0x09..0x0e Reserved
0x0f Variable Pressure (special order) 0x28 Pressure (Kilo Pascal)
6.2.2 Pressure Sensor Device Byte
The Device byte is
read-only
.
Pressure Sensor Device Byte
7 6 5 4 3 2 1 0
Reserved Type
0 0 0 0 0 0
0x00 Absolute
0x01 Gauge
0x02 Sealed Gauge
6.2.3 Pressure User Calibration Parameters
The SP-006 provides four User Calibration registers that allow setting a 2-point calibration/linearization. The
four parameters may only be set while the device is in the User Calibrate mode. When the calibration
function is triggered the device will calculate the Gain and Offset used in the linearization process. The
calibration process is performed by the following steps:
1) Send Sensor Function Calibrate Mode trigger to set the device to calibration mode.
2) Apply a known pressure and record in the User Calibration register 1 (Actual Low).
3) Record the measured value in User Calibration register 0 (Reading Low)
a. A Sensor Capture Low trigger function allows automatic capturing of the value.
4) Apply a 2 nd known pressure and record in the User Calibration register 3 (Actual High)
5) Record the measured value of the 2 nd weight in User Calibration register 2 (Reading High)
a. A Sensor Capture High trigger function allows automatic capturing of the value.
6) Send the Sensor Function Start Calibrate trigger to generate the Gain and Offset values
The four calibration parameters represent two sets of reading, where X = actual applied pressure and Y
represents the reading captured by the device. After the calibration process:
Result = Reading * Gain + Offset
Where:
Gain = (Y2 – Y1) / (X2 – X1)
Offset = (X1 * Gain) – Y1