Owner's manual

LDI Series
Linear Sensors
Omega Engineering Inc.
Wiring and Field Programmability Instructions
Standard I/O connections for a 4-conductor cable or PTO2-10 6-pin connector on an LDI linear sensor are shown below
Please note that your LDI sensor was calibrated at the factory to a specified measuring range. You may choose to retain this calibration if it suits your purpose,
or you may choose to recalibrate your sensor using the Field Programmability feature if you desire a more precise match of the sensor’s electrical output to your
mechanical device’s range of movement.
Omega’s LDI Linear Position Sensors Field Programmability feature allows the installer to very simply and quickly match the full scale electrical output of the
sensor to the actual mechanical range of movement of the device in which the sensor is installed. This type of activity is usually referred to as field calibration.
To proceed with the field calibration, follow these instructions:
1. Install the sensor into your mechanical device, leaving the sensor’s I/O unconnected.
2. Connect the black wire or common ground pin to power ground (-), and then connect the correct DC power input (+) to the sensor via the red wire or
power (+) pin.
3. To begin the Field Programmability process for voltage output, connect a DC voltmeter having the appropriate range(10 Volts) with its plus (+) test lead
connected to the green wire or analog output pin, and the meter's (-) test lead connected to the black wire or common ground pin.
4. To begin the Field Programmability process for current loop output, connect a DC milliammeter having an appropriate range with its plus (+) test lead
connected to the green wire or analog output pin and its minus (-) test lead connected to one end of the loop load resistor, typically 250 or 500 Ohms.
Connect the other end of the loop load resistor to the black wire or common ground pin.
5. Extend your mechanical device to its full range of motion, then connect the white (cal) wire or cal pin to the black wire or common ground pin for 2-3
seconds.
6. Fully retract the mechanical device to its zero or start position, then connect the white (cal) wire or cal pin to the black wire or common ground pin for
2-3 seconds.
7. The sensor’s output is now calibrated to the end points of your mechanical device's range of motion. The Field Programmability procedure can be
redone without limit, but its operational range is limited to 20% of specified full range, both at zero and at full range. (0 to 20% around zero, and 80 to
100% around full range) Note that both ends of the sensor’s range must be calibrated using the Field Programmability procedure for the process to
take effect.
8. When the Field Programmability process is completed, disconnect the voltmeter, or, in the case of current loop output, disconnect the milliammeter
and reconnect the loop load to the green wire or analog output pin. If you are using a cable output sensor, you may wish to trim and insulate the end
of the white (cal) wire to avoid an inadvertent or accidental recalibration.
SHEET
Conductor Color or Connector Pin
Red or Pin E: + Power Input: 12-30 V DC
(min. 18 V DC for 4 - 20 mA
current output)
Black or Pin D: Common Ground
Green or Pin A: Analog DC Output: 0 -10 V
or 4 - 20 mA
White or Pin B: Field Programmability (cal)
NOTE: The 4-20 mA DC output is 3-wire sourcing,
Do not connect to 2-wire loop-powered system