SMAR LD290, Operation And Maintance Manual

Page: 15 / 66

Installation
1.9
CORRECT
WIRES
INCORRECT
Figure 1.6 - Conduit Installation Diagram
NOTE
The transmitters are calibrated in the vertical position and a different mounting position displaces the
zero point. Consequently, the indicator will indicate a different value from the applied pressure. In
these conditions, it is recommended to do the zero pressure trim. The zero trim is to compensate the
final assembly position and its performance, when the transmitter is in its final position. When the
zero trim is executed, make sure the equalization valve is open and the wet leg levels are correct.
In the factory, the transmitter is ranged in the vertical position, and in this position the capacitive sensor
is in the horizontal position. If it is mounted in the field in another position, it should be ranged again to
avoid readout error. See Figure 1.8.
DIAPHRAGM SENSOR
SENSOR IN THE VERTICAL POSITION
SENSOR IN THE HORIZONTAL POSITION
HEAD OF THE FLUID
DIAPHRAGM SENSOR
Figure 1.7 - Sensor Positions
It is also recommended to ground the shield of shielded cables at only one end. The ungrounded end
must be carefully isolated.
Connection of the
LD290 should be done as in Figure 1.8.
POWER
SUPPLY
SIGNAL LOOP BE GROUNDED
AT ANY POINT OR LEFT UNGROUND
Figure 1.8 - Wiring Diagram for the LD290