51-616 Echotel Model 350/351 Ultrasonic Non-Contact Level Transmitter
4
1.4
Wiring
1.4.1 Power Wiring
NOTE: Before connecting the power line to the transmitter, be sure
that the voltage identification on the nameplate matches the
power supply. DO NOT attempt to operate this unit at volt-
ages other than as identified as it will damage the unit. Refer
to Figure 4.
NOTE: Ensure power is off before proceeding.
1. Remove housing cover and terminal strip cover.
2. No. 14 AWG wire size is the recommended maximum size
for power wiring. The power and analog output terminal
strips are marked for proper identification.
3. Bring wires into housing.
4. Attach earth ground to housing base using the green head
screw.
5. Run power leads to power terminal strip on PC board.
6. Dress wiring to ensure no interference or contact with
cover or circuit board components.
Caution:
Observe all applicable electrical codes and proper wiring
procedures.
7. Prevent moisture seepage into the enclosure by installing
approved seal-drain fittings in the conduit run leading to
the unit.
8. Replace terminal strip cover and housing cover.
1.4.2 Sensor Wiring (Model 351 Remote Only)
The sensor contains two cables which must be connected
to the transmitter. The sensor cable is the round coaxial
cable which consists of a center coaxial conductor and a
shield wrapped around it. The temperature cable is a
twisted pair.
NOTE: A minimal length of insulation should be cut off the sensor
cabling to limit contact of the bare wires with the PC board.
1. Connect center conductor of sensor cable to
X1
position
on
TB2
on the amplifier PC board in the transmitter.
2. Connect shield of sensor cable to
GND
of
TB2
.
3. Connect black wire of temperature cable, (twisted pair), to
negative (–)
TEMP
terminal of
TB2
. Refer to Figure 5.
4. The other wire from twisted pair, (red or white), is con-
nected to positive (+)
TEMP
terminal of
TB2
.
Figure 4
Transmitter Wiring
Green
Head
Screw,
Protective
Ground
V out
Ref.
GND
AC Hot
AC Neutral
Power
Loop +
Loop –
Figure 5
Sensor Wiring
X1
Gnd
+
–
Sensor
Cable
Temp.
Cable
TB2
