Greyline Instruments DFS 5.1 User manual

www.greyline.com
USER'S GUIDE
Installation & Operation
Instructions
Doppler Flow Switch
Model DFS 5.1
Manual Series 1.4

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DFS 5.1 Doppler Flow Switch
INDEX
INTRODUCTION ................................................................................................... 4
CONNECTIONS ..................................................................................................... 5
ADJUSTMENTS ..................................................................................................... 5
TRANSDUCER INSTALLATION ......................................................................... 8
ENCLOSURE INSTALLATION .......................................................................... 11
PRINCIPLE OF OPERATION ............................................................................. 11
APPLICATIONS BACKGROUND ...................................................................... 13
TYPICAL DFS 5.1 CONTROL APPLICATIONS ............................................... 14
APPLICATIONS HOTLINE ................................................................................. 15
PRODUCT RETURN PROCEDURE ................................................................... 15
SPECIFICATIONS ................................................................................................ 17
APPENDIX A - OPTIONS ................................................................................... 18
APPENDIX B ........................................................................................................ 20
IMPORTANT NOTE: This instrument is manufactured and calibrated to meet product specifications.
Please read this manual carefully before installation and operation. Any unauthorized repairs or
modifications may result in a suspension of the warranty.
Available in Adobe Acrobat pdf format

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DFS 5.1 Doppler Flow Switch
INTRODUCTION
DOPPLER FLOW SWITCH - Model DFS 5.1
The Greyline Doppler flow switch consists of an encapsulated ceramic transducer, a transmitter/receiver
unit, electronic circuitry to separate the Doppler frequency from the transmitted frequency and an
adjustable set-point relay. The relay also has hysterisis and delay-off capability.
The DFS 5.1 Flow Switch is housed in a watertight NEMA4X fiberglass enclosure and requires a
115VAC power supply.
Flow measurement range is 0.25 to 10 ft/second (0.076 to 3 m/sec).

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DFS 5.1 Doppler Flow Switch
CONNECTIONS:
SENSOR: Connect one sensor
coaxial cable to the Rx and GND
terminal block, and the second sensor
coaxial cable to the Tx and GND
terminal block. Tx and Rx are the
solid core of each coaxial cable, and
GND is the stranded shield of each
coaxial cable. (See page 17 for coaxial
cable preparation).
POWER INPUT: Connect 115VAC
50/60Hz to the LINE, NEUTRAL and
GROUND terminals. Do not apply
power until sensor connections have
been made.
Note
Tx = Transmitter
Rx = Receiver
Nc = Normally closed contacts
No = Normally open contacts
C = Common
ADJUSTMENTS:
Bar Graph
Display
The green LED’s indicate flow velocity. The red
LED indicates relay energized see chart for
calibration.
Relay Trip Point Insert shorting link at the flow rate indicated by
the bar graph display. A second link can be
inserted to provide a relay deadband.
Alarm State Select high flow alarm or low flow alarm by
inserting the shorting link.
Relay Drop-out
Delay
Adjust delay in 5 second increments to prevent
relay chatter on intermittent flow.

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DFS 5.1 Doppler Flow Switch
DFS 5.1 DOPPLER FLOW SWITCH CALIBRATION

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DFS 5.1 Doppler Flow Switch
DFS 5.1 DOPPLER FLOW SWITCH CALIBRATION

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DFS 5.1 Doppler Flow Switch
TRANSDUCER INSTALLATION
MOUNTING LOCATION - The position of the sensor is one of the most important considerations for
reliable flow monitoring. The same location guidelines apply to Doppler as to most other types of flow
switches.
VERTICAL OR HORIZONTAL PIPE - Vertical pipe runs
generally provide evenly distributed flow conditions. On
horizontal runs the sensor should be positioned at 3 or 9
o’clock to avoid concentrations of gas at the top of the pipe
and solids on the bottom.
Generally the sensor must be mounted away from flow disturbances such as valves, pumps, orifice
plates or venturis which tend to increase flow velocity or cause cavitation. Velocity increasing devices
often cause cavitation and erratic operation. As a guideline, mount the sensor 20 diameters upstream and
30 diameters downstream from velocity increasing devices.
Turbulence Increasing Devices: Elbows, flanged
connections and tees tend to introduce desirable
conditions of an evenly distributed flow profile with
some air or gases entrained in the flow. Sensor
mounting 6 diameters upstream and 10 diameters
downstream from these disturbances is generally
optimum.
The transducer is designed to mount longitudinally on a straight section of pipe. Do not attempt to
mount it on bends, elbows or fittings. The DFS senses flow in either direction.
Prepare an area 2 inches wide by 3 inches long for transducer bonding by removing all paint, scale and
rust. Thoroughly degrease the surface to which the transducer will be bonded. The objective of site
preparation is to eliminate any discontinuity between the transducer and the pipe wall which would
prevent acoustical coupling.
For semi permanent or temporary bonding, the following are recommended:
a) Dow Corning silicon compound #4. (Greyline Part #CC)
b) Electrocardiograph gel.
c) Petroleum gel.
The above are arranged in their order of preferred application. B & C are suggested only for room
temperature application. DO NOT USE: Silicon RTV compound (silicon rubber).

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DFS 5.1 Doppler Flow Switch
One PCK2 Pipe Clamp Kit is included with each Greyline DFS 5.1. It includes recommended silicone
coupling compound in a plastic applicator, a stainless steel sensor bracket, and a stainless strap for pipe
diameters up to 16” 406 mm. Additional pipe clamps (optional) may be attached for larger diameter
pipes.
Thread the strap through the bracket and mount loosely on the pipe ready for Sensor coupling.
SENSOR COUPLING
Prepare a pipe clamp to secure the sensor. Apply coupling compound to the coloured face of the sensor.
A bead (similar to toothpaste on a toothbrush) is ideal. Press the sensor on to the pipe and secure with
the clamp. DO NOT over tighten.
For proper operation the transducer must be fixed securely to the pipe with coupling material between
the transducer face and the pipe. Sensor installation with excessive coupling compound or use of epoxy
can result in gaps or voids in the coupling and cause errors or loss of signal. Insufficient coupling
compound will create similar conditions.
Over time temporary coupling compounds may gradually sag away from the sensor resulting in reduced
signal strength and finally complete loss of signal. Warm temperatures, water and vibration will
accelerate this process. Loss of Signal will be indicated by erratic performance of the DFS 5.1.

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DFS 5.1 Doppler Flow Switch
SENSOR COUPLING AND MOUNTING RECOMMENDATIONS

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DFS 5.1 Doppler Flow Switch
ENCLOSURE INSTALLATION
NEMA4X (IP66) WITH CLEAR COVER
LOCATION - Select a wall location within 20 ft (6 m) of the sensor mounting location. Sensor cable
may be extended up to 500 ft (150 m) if enclosure installation is required at a remote location.
To protect the electronics from overheating and condensate build-up DO NOT mount the enclosure in
direct sunlight. Avoid mounting on vibrating structures.
1. Remove enclosure cover.
2. Insert #6 screws through the enclosure mounting holes to secure the
enclosure to the wall or mounting stand.
3. Replace cover.
Note: This non metallic enclosure does not automatically provide grounding
between conduit connections. Grounding must be provided as part of the installation. Ground in
accordance with the requirements of the National Electrical Code. System grounding is provided by
connecting grounding wires from all conduit entries to a steel mounting plate or another point which
provides continuity.
PRINCIPLE OF OPERATION
Greyline Doppler flow instruments continuously inject sound into the flowing liquid and measure the
change in frequency of any echoes received from suspended particles, air bubbles, etc. in the liquid.
The sound frequency of 640,000 wave-lengths/second travels through the liquid at 4,800 feet/second
(for water). The 640,000 wave-lengths occupy 4,800 feet. If the target is moving away from the
receiver, the same number of wave-lengths has to occupy a bigger distance and so each wave-length
appears longer. The longer wave-length means fewer wave-lengths/second or a lower frequency. The
reverse is true if the target moves towards the receiver; the distance is shortened, the wave-length
appears shorter and the frequency higher.
The Doppler Flow Switch measures only the change in frequency and will read the same whether the
flow is towards or away from the transducer.

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DFS 5.1 Doppler Flow Switch
SENSOR CABLE RESISTANCE TEST
Unplug the green sensor terminal from the Doppler board and connect the sensor wires as shown. With a
multimeter, perform resistance checks for each set of wires. One single loose terminal may cause false
readings.
Test across shield and core of each wire: TMTR (black/white) and RCVR (black). Resistance should be
around 82.5K ohms for any cable length. High readings indicate an open circuit and low readings
indicate a short or partial short in the sensor cable.

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DFS 5.1 Doppler Flow Switch
APPLICATIONS BACKGROUND
PIPE MATERIAL - Porous materials such as concrete or pitted cast iron cause sound attenuation and
Doppler performance may be erratic. Steel, aluminum, copper, PVC and other plastic pipes are
generally ideal with minimal sound attenuation.
Avoid pipes with loose insertion liners where sound transmission may be broken by air gaps.
PIPE DIAMETER - The standard SE4 sensor is designed to mount on pipes 1/2 inch (12.5mm) I.D. or
larger.
DEPOSITS - Scale or sediment deposits in older pipes can cause sound attenuation and reduce Doppler
signal strength which is automatically compensated by the receiver circuits.
NOISE INTERFERENCE - The Doppler circuit is designed to lock onto the strong Doppler return
signal and to ignore most external process noise. Marginal applications, where the liquid contains
minimal solids or gases may be more sensitive to external noise.
ELECTRICAL INTERFERENCE - High voltage sources or DC motors in very close proximity to the
Doppler sensor, cable or electronics, can interfere with the Doppler signal. Stray mains voltage (50 or
60 Hz) can occasionally be measured on conductive pipes and care should be taken to eliminate the
problem at its source.
POWER LINE FLUCTUATIONS - Voltage variances of ±10% of the instrument’s nominal input will
not affect performance or accuracy.
FLUID TEMPERATURE - Within the sensor tolerances (-40° to 300°F/ -40° to 150°C) the DFS 5.1
performance will not be affected. Higher or lower temperatures may damage or reduce the operating life
of the sensor.
CALIBRATION DRIFT - The DFS 5.1 calibration does not drift over time. The solid state sensor has
no moving parts to wear and affect calibration. The Doppler principle generates a digital signal
proportional to the velocity of flow. All timing/counting circuits use crystal controlled references to
eliminate any drift in the processing circuitry.

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DFS 5.1 Doppler Flow Switch
TYPICAL DFS 5.1 CONTROL APPLICATIONS

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DFS 5.1 Doppler Flow Switch
APPLICATIONS HOTLINE
For applications assistance, advice or information on any Greyline Instrument contact your Sales Representative,
write to Greyline or phone the Applications Hotline below:
United States: Tel: [phone] Fax: [phone]
Canada: Tel: [phone] Fax: [phone]
Toll Free: 888-473-9546
Email: [email protected]
Web Site: www.greyline.com
Greyline Instruments Inc.
Canada USA:
16456 Sixsmith Drive 11451 Belcher Road South
Long Sault, Ont. K0C 1P0 Largo, FL 33773
PRODUCT RETURN PROCEDURE
Instruments may be returned to Greyline for service or warranty repair.
1 Obtain an RMA Number from Greyline -
Before shipping a product to the factory please contact Greyline by telephone, fax or email to obtain an
RMA number (Returned Merchandise Authorization). This ensures fast service and correct billing or
credit.
When you contact Greyline please have the following information available:
1. Model number / Software Version
2. Serial number
3. Date of Purchase
4. Reason for return (description of fault or modification required)
5. Your name, company name, address and phone number
2 Clean the Sensor/Product -
Important: unclean products will not be serviced and will be returned to the sender at their expense.
1. Rinse sensor and cable to remove debris.
2. If the sensor has been exposed to sewage, immerse both sensor and cable in a solution of 1 part
household bleach (Javex, Clorox etc.) to 20 parts water for 5 minutes. Important: do not immerse
open end of sensor cable.
3. Dry with paper towels and pack sensor and cable in a sealed plastic bag.
4. Wipe the outside of the enclosure to remove dirt or deposits.
5. Return to Greyline for service.

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DFS 5.1 Doppler Flow Switch
LIMITED WARRANTY
_____________________________________
Greyline Instruments warrants, to the original purchaser, its
products to be free from defects in material and workmanship for a
period of one year from date of invoice. Greyline will replace or
repair, free of charge, any Greyline product if it has been proven to
be defective within the warranty period. This warranty does not
cover any expenses incurred in the removal and re-installation of
the product.
If a product manufactured by Greyline should prove defective
within the first year, return it freight prepaid to Greyline
Instruments along with a copy of your invoice.
This warranty does not cover damages due to improper installation
or handling, acts of nature, or unauthorized service. Modifications
to or tampering with any part shall void this warranty. This
warranty does not cover any equipment used in connection with the
product or consequential damages due to a defect in the product.
All implied warranties are limited to the duration of this warranty.
This is the complete warranty by Greyline and no other warranty is
valid against Greyline. Some states do not allow limitations on how
long an implied warranty lasts or limitation of incidental or
consequential damages, so the above limitations or exclusions may
not apply to you.
This warranty gives you specific legal rights, and you may also
have other rights which vary from state to state.
Greyline Instruments Inc.

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DFS 5.1 Doppler Flow Switch
SPECIFICATIONS
Sensor Mounting: Silicone coupling compound,
PCK stainless steel Pipe
Clamp Kit for 0.5" / 12.5 mm
OD pipes or larger
Electronics Enclosure: watertight, dust-tight NEMA4X
(IP67) polycarbonate
Output: 1 Relay – 5 ampere DPDT
Set Point: On/Off adjustment 0.25 – 10
ft/sec (0.076 – 3 m/sec)
Relay Time Delay: adjustable, 0-60 seconds
Failsafe Mode: switch selectable
Indication: Relay and Signal strength
LED’s
Sensitivity: Automatic
Power Input: 100–240VAC 50-60Hz, (2.0 W max.)
Optional: 12–24VDC, (3.0 W max.)
Surge Protection: sensor, AC power input
STANDARD SENSOR SE4
Minimum Pipe Diameter: 0.5" (12.5 mm) ID, 0.6" (15 mm) OD
Maximum Pipe Diameter: 180" (4.5 m) ID
Operating Temperature: -40° to 300°F (-40° to 150°C)
Operating Frequency: 640 KHz
Sensor Housing: Stainless Steel
Sensor Cable: 20 ft. (6 m) shielded coaxial pair (RG174U)
Optional 50 ft (15 m) or 100 ft (30 m) continuous
Submersion Rating: Withstands accidental submersion pressure up to 10 psi (0.7 Bar)

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DFS 5.1 Doppler Flow Switch
APPENDIX A - OPTIONS
EXTRA SENSOR CABLE
(OPTION DXC)
Each Greyline flow switch includes 20 ft. (6m) shielded coaxial pair cable. Additional cable and Cable
Junction Box (Option JB2X) may be ordered with the Flow Switch, or the cable may be spliced and
extended up to 500 ft (152m) as required during installation. No adjustment is required when the sensor
cable is extended or shortened.
Use only Greyline shielded coaxial pair cable. Extended sensor cable can be installed in conduit for
mechanical protection. Recommended installation with a JB2X junction box is illustrated below:
Note: Instead of Greyline Option DXC shielded coaxial pair, you may substitute RG174U coaxial cable
from your local electrical cable distributor but this cable is not shielded so extended cable must be
installed in metal conduit.
COAXIAL CABLE PREPARATION
DXC Doppler sensor cable can be cut and spliced up to a maximum length of 500 ft (152 m). Cable ends
must be prepared as illustrated below.

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DFS 5.1 Doppler Flow Switch
SENSOR CABLE JUNCTION BOX
(OPTION JB2X)
Optional Watertight NEMA4 Junction Boxes with terminal strips are available from Greyline
Instruments.
24VDC POWER INPUT
(OPTION DC)
DFS 5.1 DC Flow Switches are factory configured for 12-24VDC power input.

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DFS 5.1 Doppler Flow Switch
APPENDIX B
FLOW VELOCITY CALCULATION
Flow velocity can be calculated from the following data.
KNOWN FLOW DIVIDED BY VELOCITY
U.S. gallons/sec. 0.0408 x (pipe I.D.")² = ft/sec
U.S. gallons/min. 2.448 x (pipe I.D.")² = ft/sec
Imp. gallons/sec 0.0340 x (pipe I.D.")² = ft/sec
Imp. gallons/min 2.040 x (pipe I.D.")² = ft/sec
Litres/sec 0.1545 x (pipe I.D.")²
= ft/sec
Litres/min 9.270 x (pipe I.D.")² = ft/sec
Cubic metres/sec 0.0001545 x (pipe I.D.")² = ft/sec
Cubic metres/min 0.00927 x (pipe I.D.")²
= ft/sec
EXAMPLE: 3" ID pipe
Known Flow of 160 US gallons/min: 160 = 7.26 ft/sec
2.448 x (3)²