Greyline Instruments DFS-5.1 Specifications

Control Flow From Outside a Pipe

Flow Switch with SensorNon-Contacting

Doppler Flow

Switch

Model DFS 5.1

Controls Flow with:

No pressure drop

No sensor fouling

No maintenance

Installs in Minutes

No moving parts

Ideal for "difficult" liquids

No contact, No maintenance

Easy Calibration

Clamp-on Flow Sensor

Installs without cutting the pipe

Mount the DFS 5.1 ultrasonic sensor on the outside of metal or
plastic pipes. The sensor continuously injects high frequency
sound through the pipe wall and into the moving fluid where
acoustic pulses are reflected back to the sensor from particles or
bubbles in the fluid.

Flow rates of most liquids can be accurately controlled including
acids, caustics, lubrication fluids, chemicals, abrasives, waste
water and sludge. There are no moving parts and no sensor
maintenance is required.

The compact, water tight electronics enclosure includes adjustable
controls with separate ON and OFF relay set-points and time delay.
A LED bargraph for flow rate and set points plus relay status are
included.

Installation can be made while the flow system is in full operation.
No contact is made with the moving fluid and no holes are drilled in
the pipe. There is no fouling or scale build-up on the sensor.

Non-Contacting Flow Control

Pump protection … High or Low flow control

Overfill alarm … Bargraph flow rate indication

Each DFS 5.1 Flow
Switch Includes:

!

Adjustable ON and
OFF relay setpoints

!

Adjustable time delay

!

Flow rate bargraph

!

Relay LED

Install in these
Applications:

] Sewage

] Viscous liquids

] Acids

] Slurries

] Solvents

] Treated wastewater

No pipe cutting, No pressure drop,
No sensor fouling, No maintenance!

It takes just a few minutes to install and calibrate a DFS 5.1 Flow Switch. The
DFS 5.1 controls flow of most liquids in closed pipes. The ultrasonic sensor
mounts on the outside of any pipe from 1/2" to 180" (12.5 mm to 4.5 m) I.D.

Easy to Calibrate

The DFS 5.1 control relay can
be set to turn ON and
OFF at any flow rate
between 0.25 and 10
ft/sec (0.075 to 3
m/sec). Insert two
links for separate
ON/OFF set points or
just one link for a Hi or
Lo flow alarm. Set relay
actuation time delay
from 0 to 80 seconds.

Ideal for Pump Protection

Avoid expensive pump repairs and downtime. The DFS 5.1 strap-on Sensor can
be installed in minutes without shutting down flow or cutting pipe. Use the
adjustable relay time delay to eliminate relay "chatter" and reduce pump wear.

] Sludge

] Pulp stock

] Food products

] Oils

Reliable and Repeatable

Repeatability is ±0.1% of full scale (0.1 ft/sec or 0.003 m/sec). There are no
moving parts and no maintenance is required.

The clamp-on ultrasonic sensor cannot be damaged or fouled by contact with the
liquid it measures. Sealed in a stainless steel housing, the DFS 5.1 sensor
withstands moisture or accidental submersion in water up to 10 psi (69 Kpa).

] Paint

] Chemicals

] Aerated Water

] Cooling Water

Designed for "difficult" liquids

The DFS 5.1 Doppler Flow Switch is recommended for flow
control of liquids containing gas bubbles or solids: chemicals,
slurries, sewage, sludge, viscous liquids, wastewater, caustics
and abrasives. The ultrasonic sensor injects high frequency
sound through the pipe wall into the flowing liquid. Acoustic
pulses are continuously reflected back to the sensor and the
DFS 5.1 measures a frequency shift to calculate flow velocity.

Self-tunes to Extended Sensor Cable

Up to 500 ft (150 m) extra sensor coaxial cable can be added. Extended cable
and junction box can be ordered from Greyline. The cable can be cut or extended
as required during installation. The flow switch automatically tunes to the cable
length. No circuit adjustment or calibration is required

SENSOR

BUBBLES OR SOLIDS
REFLECT SOUND

SOUND WAVES
REFLECTED
BACK TO SENSOR

SOUND WAVE
TRANSMITTED
FROM SENSOR