Honeywell SWW DATASHEET

24 I Flow monitors

SWW series

For monitoring flow of liquid and piped, gaseous media

max. 60 m

shielded cable 4

ASW 454

Technical data of sensor

General

The flow sensor in stainless steel 1.4571 is
suitable for lightly contamina
a

lso aggressive media provided the material is
compatible. Flows in gaseous media can also
be monitored with this sensor

Medium temperature 0…80
Higher medium temperatures (up to 120°C)
may cause a deviat
but cannot damage the sensor.

Temperature compensation up to 80°C

Sensor material

In contact with medium: stainless steel 1.4571
Casting compound: Wepuran (vu 4459/41 sv)
Cable gland: Nickel-plated brass

Max. permitted pressure 20 bar
Process connection G 1/4’’ or G 1/2’’
Connection cable four-core, 2.5 m long
Degree of protection IP 65

ted media, and

.
°C.

ion of the switching point

1.5 mm

x

2

T

he flow in fluids can be monitored reliably with
flow sensors SWF 62 and SWF 62 L and
evaluation unit ASW 454.

T

he sensitivity can be adjusted accurately with
a rough and fine potentiometer. The switching
state is indicated by LED. The sensor element
must be located in the flow.

SWF 62

i

Function

The flow monitors work according to the calorimetric principle. A thermistor is heated up. As heat is
withdrawn by the flowing medium, the thermistor resistance alters. The change in resistance is
evaluated. As the resistance also depends on the temperature of the medium, the difference must be

mined by a second thermistor. The difference is compensated and in this way the switching point

deter
is kept stable. When monitoring high flow rates, rapid temperature fluctuations can trigger switching
operations. Suspended materials adhering to the sensor can have an insulating effect and so affect
the measur

ement result and hence the defined switching point. Therefore it is advisable to remove any

dirt during routine maintenance operations.

Product Summary

Sensors Screw-in thread Sensor length (from thread) Thread length Type

G 1/4 25 mm 23 mm SWF 62
G 1/2

45 mm 18 mm SWF 62 L

Technical data of evaluation unit

Power supply

230
(see Product Summary)

Power consumption approx. 3 VA

Contact load

Relay, single pole
8 A, max. 250 VAC

Ambient temperature 0 - 60

Max.

Flow rate

0.1…3 m/s (liquid media) 1…15 m/s
(gaseous media)

Response time approx. 20 – 60 s

Repetition accuracy

2%, relative to the flow rate at the sensor.

<

Switching hysteresis

Approx. 2% of overall range.

Max.

aluation unit

ev

60 m,

Sensor protection

In case of breaka
sensor wires,
interruption of flo

Type of construction Standard housing N 45
Weight approx. 0.35 kg

VAC/DC

AC or 24

V

C

°

temperature gradient

cable length between sensor and

for shielded cable 1.5 mm

ge or interruption of the

the unit switches off or an

w is signaled.

10 K/min.

2

.

Evaluation units Supply voltage Type

230 V AC ASW 454
24 V AC/DC

i

Operator interface Wiring diagram

Adjusting elements

Sensitivity (rough and fine)

In case of malfunction,
a sensor error can be ruled out
by checking the resistances
between the connecting wires
of the sensor
SWF62L must be disconnected
and checked with a suitable
ohmmeter between the
individual connecting wires:

White-bro
White-green approx. 1.0 kOhm
White-yellowapprox. 1.0 kOhm

The terminal voltage of the
evalua
ASW 454/24 can also be
checked with a voltmeter
between the
terminals after disconnecting
the sensor.

14.8 VDC is the correct value.

. Sensor SWF62 or

pprox.

a

wn

tion units

“+” and “Gnd”

(high sensitivity at low flow)

Signal lamps

1 = Flow present
2 = Supply voltage present

ASW 454/24

0.2 kOhm

ASW454 or

s

otection:

ee of pr

Degr
IP 65 (sensor)
IP 32 (evaluation unit)