Omega Engineering ULTRASONIC LEVEL TRANSMITTER LVU-90 - Manual (Page 4)

Step Four Step Five
WIRING INSTALLATION
The LVCN-90 transmitter may be installed through the top wall of a
tank. Installation requires a 3/4" NPT fitting or blind flange.
1. Install the appropriate 3/4" fitting in the top wall of the tank. Prior
to installation, make sure that the fitting has been installed prop-
erly and checked for leaks. Use a proper sealant at the time of
installation to ensure a liquid-tight seal. Secondly, make sure that
the fitting’s threads are not damaged or worn.
2. Insert the Transmitter into the fitting and tighten to hand tight.
3. Always check for leaks prior to system start-up. To ensure proper
installation, a complete leak test and simulation of actual process
conditions should be preformed.
Flange Fitting
Installation Installation
Warning
Do not install the LVCN-90 in pressurized applications above 30
psi.
Always install the 3/4" Viton gasket with the LVCN-92. The
LVCN-92 G threaded version will not seal unless the gasket is
installed properly.erly and checked for leaks.
Use a proper sealant at the time of installation to ensure a liquid-
tight seal. Secondly, make sure that the fitting’s threads are not
damaged or worn.
Follow the instructions in Step 3 for wiring to the LVU-90.
1. Wiring to an OMEGA Continuous Controller (LVCN-51):
Connect the (+) terminal to the positive 24 VDC, 25 mA terminal
on the controller. Connect the (-) terminal to the GND terminal on
the continuous controller (See illustration below). Check LVCN-
51 instruction manual for setting the LVCN-51 for loop powered
operation.
2. Wiring to a Two-Wire Loop Powered Indicator:
The LVCN-90 requires 12-36 VDC power and an indicator which
receives a 4-20 mA current input. Connect the (+) terminal of the
LVCN-90 transmitter to the positive VDC terminal on the power
supply. Connect the (-) terminal on the LVCN-90 to the (+) ter-
minal on the loop indicator. Connect the (-) of the loop indicator
to the (-) of the power supply (See illustration below).
3. Wiring to a Typical PLC:
The LVCN-90 requires a PLC which provides a 12-36 VDC exci-
tation and receives a 4-20 mA current input. Connect the (+) ter-
minal of the LVCN-90 transmitter to the positive VDC power ter-
minal. Connect the (-) terminal on the LVCN-90 to the (+) chan-
nel on the PLC. Connect the (-) of the PLC to the (-) of the power
terminal (See illustration below).
* 250
Ω
resistor typically internal to PLC
LATCH
ON OFF
P W R R E L AY 1
INVERT DELAY
R E L AY 2
INVERT DELAY
4 20 OP
E A S Y CAL
UP DOWN SET INPUT 0% 100%
OFF SET SP
AN
RL
Y1
RL
Y2A
RL
Y2B
POWER
4-20 mA
(-) (+)
GND 12-36 VDC
- +
- + + -
DC Power
Supply
12-36 VDC
POWER
4-20 mA
(-) (+)
GND 12-36 VDC
- +
+ -
DC Power
Supply
12-36 VDC
T
ypical PLC
6
5
4
3
2
1
0
A
250
Ω
POWER
4-20 mA
(-) (+)
GND 12-36 VDC
- +
VACUUM
Avoid
Interference from
side of tank
Do not
install at
an angle
Avoid
Interference from
obstructions in
tank
LVCN-90 will
not operate in
vacuum