Dwyer BFM User Manual

Bulletin FL-1-BFM

4x 3/4˝ CONDUIT KNOCKOUTS

5-9/64 [130.45]

TRANSFORMER

3[76.20]

6X 1/2˝ CONDUIT
KNOCKOUT

1-19/32

[40.64]

1/2

[12.69]

3/32

[2.29]

3

[76.20]

1-1/2

[38.10]

FLOW SENSOR

6´ 18 AWG

WIRE

SENSOR

TIP

PRODUCT LABEL
FOR MAIN CONTROLLER UNIT

7

[177.80]

GREEN

LED

1A FUSE

RED LED

RELAY

SENSITIVITY ADJUSTMENT

POTENTIOMETER

BFM FLOW MONITOR

Series BFM Bulk Flow Monitor

Specifications - Installation and Operating Instructions

BFM

Series BFM Bulk Flow Monitor provides effective

monitoring for most flow/no flow conditions in pipes and
chutes. It’s sensing techniques, which use a Piezo element,
makes the BFM versatile for most flow/no flow applications.

BFS

SPECIFICATIONS
BFM Specifications
Service: Solids and liquids.
Power Requirement: 120VAC, 220VAC or 12VDC.
Power Consumption: .1A.

The BFM Control offers many unique advance features

that exceed the industry standards. The BFM Central
Processing Unit monitors movement of almost anything
through a pipe or chute system. The BFM is ideal for
sensing the presence or absence of materials in Pneumatic
Conveying Systems. The BFM offers adjustable sensitivity
depending on the application demand. Also, it provides
easy installation and requires no maintenance. The unit has
L.E.D indicators – flow (green)/ no flow (red).

Temperature Limits: 120°F (48.9°C).
Output: Relay: SPDT rated 4A @ 125/250VAC, 1/10 HP

@ 125/250VAC, 3A @ 30VDC. TTL: 0-5 V.

Serial Communications: RS-232.
Electrical Connection: Screw Terminal.
Conduit Connection: Knockouts (two 3/4˝ for power,

three 1/2˝ for sensor and outputs).

Enclosure Rating: NEMA 4.
Material: Polycarbonate.
Weight: 3 lbs (1.36 kg).

The BFS-1 Sensor yields many advance features. It

externally mounts to the outside of the pipe or chute. It
provides mounting tabs for easy installation. The Sensor is
prewired with 3´ wire.

BFS Specifications
Pipe Size: 1/2˝ to 60˝ (1.27 to 152.4 cm).
Enclosure Rating: NEMA 4.
Electrical Connection: 3´ (0.9 m) of 18 gauge wire.

Series BFM has many practical applications. You can use it
to monitor Oil Spray Systems, Discharge Chutes,
Distributors, Screw Conveyors, Drag Conveyors, Water
Systems, Air Systems, Pneumatic Systems, Gravity Feed
Systems, Slurry Systems, Chemical Processing, Food
Processing and Rotary Drums.

DWYER INSTRUMENTS, INC.

P.O. BOX 373 • MICHIGAN CITY, INDIANA 46361, U.S.A. Fax: [phone] e-mail: [e-mail]

Part Number
BFM-1
BFM-2
BFM-3
BFS-1

Temperature Limits: 155°F (68.3°C).
Materials: PVC Type 1 Grade 1 Grey.
Weight: 5 oz (141.8 g).

Descriptions

Control Unit: NEMA 4X, Polycarbonate Housing, Weatherproof, 120VAC
Control Unit: NEMA 4X, Polycarbonate Housing, Weatherproof, 220VAC
Control Unit: NEMA 4X, Polycarbonate Housing, Weatherproof, 12VDC
Sensor

Phone: [phone] www.dwyer-inst.com

3/4˝ HIGH

VOLTAGE INPUT

1/2˝ LOW

VOLTAGE INPUT

BFM WIRING

The BFM polycarbonate housing comes with 10 PG conduit
knockouts in the housing.

• High voltage inputs above 24 volt AC should be routed into
the housing through the 3/4˝ (20mm) conduit hole.

• All Low voltage wiring (TTL, RS232, and sensor) should be
routed through the 1/2˝ (14mm) conduit hole.

• A 1-Amp fuse is located next to the transformer .

Figure 3

Figure 1

HIGH VOLT AGE INPUTS

Connect the 120VAC, 50/60 HZ, 1 Amp supply on TB2
terminals (Fig. 2):

• 120VAC (Hot) supply to 117V AC terminal (or 12VDC, 240V AC

per the model)

• AC Common to AC COM terminal

• Earth-Ground to E GND terminal. Must connect to prevent
accidental electrical shock.

SENSOR INPUTS

Connect the low voltage Flow Sensor to the Sensor terminals
TB1 (Fig. 4):

• Positive RED (or White) sensor lead to the “+” Sensor
terminal on TB1.

• Negative BLACK sensor lead to the “-” Sensor terminal on
TB1.

The sensor wiring should be a minimum of 18 AWG strand­ed 2-conductor cable. Use 18 AWG for up to 500´ (155m) and
16 GA up to 2000' (620m).

• All Sensor wire splices must be SOLID and WATER TIGHT.

Figure 2

Figure 4

RELA Y AND LOW LEVEL LOGIC WIRING

SIDE VIEW FRONT VIEW

BFM

SENSOR

BFM

SENSOR

NOTE: PILOT HOLES

ARE DRILLED INTO

FLAT SURFACE AND

MOUNTED WITH

PORPER HARDWARE.

See those sections later in this manual.

SENSOR INST ALLATION

The BFS-1 sensor is in very a rugged polymer housing with a
sealed 6´ cable pigtail (Fig. 5):

• Red/Black = Positive

• White/Black = Negative (this is electrically connected to the
metal sensor stud)

BFM SENSOR

BLACK LEAD

Figure 6

MOUNTING TO A ROUND OR NON-FLAT SURFACE:
(FIG. 7)

• Using strapping (such as heavy duty wire-ties) or clamps to
secure the sensor housing to the pipe so the metal sensing

stud makes firm contact with the surface.

RED/WHITE LEAD

Figure 5

MOUNTING PROCEDURES FOR SENSOR:

The BFS-1 Sensor can be screwed, clamped or strapped in
place and is able to detect flow through most sheet metal.

• Clean the surface area where the sensor is to be installed.
The surface should not have any buildup or scale but does
be perfectly clean.

• The sensor stud located at the bottom of the sensor
housing must make solid contact with the surface of the
pipe to be monitored.

MOUNTING TO A FLA T SURFACE:

Refer to the mounting holes located at each end of sensor
housing (Fig. 6).

• Mark mounting holes.

• Drill pilot holes for mounting screws.

• Screw sensor housing to flat surface.

BFM

SENSOR

SIDE VIEW FRONT VIEW

NOTE: STRAPS

OR CLAMPS
ARE USED FOR
MOUNTING TO

NON-FLAT

SURFACE

Figure 7

BFM

SENSOR