Gems Sensors & Controls ULS-10, ULS-100 Specifications

ULS-100/10

Ultrasonic Liquid Level Switches

Instruction Bulletin No. 146077

General Description

The ULS-100/10 Series Liquid Level Detection System is an ideal, low cost, ultrasonic liquid
level detection system for many applications. It operates in a broad spectrum of viscous to
light liquids.

Principle of Operation

The ULS-100/10 Series operates using ultrasonic sound wave propagation. Ultrasonic sound
waves are greatly attenuated when transmitted through air. Conversely, when liquid is
present, transmission of the sound waves is greatly enhanced. The electronic control unit
generates electrical signals that are converted to bursts of ultrasonic energy at the sensor. The
ultrasonic bursts are transmitted across the liquid sensing gap. Upon receipt of a valid signal,
the solid-state electronics generate a data enable condition, indicating liquid is present. This
signal energizes a relay to provide a contact closure or a 4 mA/20 mA, 2-wire current output.

GEMS

Model No.

ULS-100

ULS-10

1. Standard sensor for contact type point level: 316 stainless steel.

2. Different sensor materials include Monel, Hastalloy, Titanium, Teflon,
Kynar, CPVC, PVC or any special metal, alloy. Consult Factory.

Mounting

Type

Integral
Remote

Integral
Remote

Model Description

Input Power

115 VAC/230 VAC
24 VDC/12 VDC

115 VAC/230 VAC
24 VDC

Notes:

Output

10 Amp DPDT
" "

10 Amp DPDT
2-wire 4/20mA

Function

Standard Point
Level

Standard Point
Level

3. 3/4" NPT is standard, different NPT and flanges are optional.

4. Standard length of sensor is 1". Extension up to 120" is available.

Installation

General

The unit is easy to install. The sensor, with its integral electronics control unit, can be mounted
in any position or orientation desired. Remote-mounted electronics are also possible.

Make sure that all wiring, conduit and electrical fittings conform to local Electrical Codes for
the location selected.

Visual Inspection

Unpack the control unit and sensor assemblies. Visually inspect them for any damage. Ad­vise Factory immediately if either assembly is damaged.

Preliminary Operational Check

Before installing the unit, a simple operational check-out should be performed:

1. Fill a container with liquid.

WARNING: In a hazardous environment, never open housing cover or connect
power leads without first disconnecting electrical power at the source.

2. Open the control unit housing cover and connect power to the control unit. (See Wiring
Diagram - Page 5.)

3. Apply power from the source.

4. Place the sensor in the liquid. Relay should energize. If current source, current will
change from 4 mA (dry) to 20 mA (wet).

5. Remove sensor from the liquid. Relay will deenergize. System is functioning properly.

6. Disconnect power to the control unit.

7. Proceed to final installation.

If the system does not function, notify the Factory immediately.

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Final Installation

Invasive Contact Type

Follow the instructions below:

1. Drill a suitable hole in the vessel or pipe wall and tap for 3/4" NPT. In thin walled
vessel or material not suitable for threading, weld or braze a bushing to accept the
sensor.

2. Screw the sensor in the threaded section and make sure that there is a good seal. Use a
pipe compound or sealing tape to avoid excessive tightening. Do not overtighten.

3. Run the power and control wiring cables to the electronics control unit.

Observe all applicable electrical codes and proper wiring procedures.

Wiring Diagram

Model ULS-100

Jumper

High Level

Fail Safe

Jumper
Normal

Position

Coaxial

Cable To

Sensor

J1

J2

CNCNOCNCL1

NO

DPDT

SPDT

POWER

L2 G

115 AC

50/60 HZ

Note

24V DC or 12V DC
Connect Positive (+) to L1 - Terminal
Connect GND ( ) to G - Terminal

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