Huba 694 Service Manual

HUBA-REGISTERED TRADE MARK

694

Pressure, vacuum and

differential pressure

transmitter

0 to 50 mbar

Huba Control

FOR FINE PRESSURE AND FLOW MEASUREMENT

EDITION 07/2001

Technical overview

The differential pressure transmitters
of the Type 694 series incorporate
a proved ceramic fulcrum lever tech­nology. They deliver calibrated,
temperature-compensated sensor
signals, available as standard volta­ge or current outputs. They are ide­al for registering low air flow in air
conditioning systems and for the
measurement of fine pressures in en­vironmental, laboratory and clean­room applications (air and
non-corrosive gases).

Pressure ranges

See order code selection table.

Overload

See order code selection table.

Rupture pressure

500 mbar

Accuracy

Linear output:
Zero point < +/- 0.7 % fs
(Type 0 – 1 mbar < +/- 1.0 % fs)
Linearity inclusive
hysteresis < +/- 1.0 % fs
(Type 0 – 1 mbar < +/- 2.0 % fs)

Total of linearity, hysteresis, repea­tability and zero point:
from - 50 to + 50 Pa

< ± 3 Pa (3% FS)

Square-root extracted output:
Absolute error
(from 2 ... 100 % pressure)

≤ +/- 0.3 + 1.5

[% of full scale]

Type 0 – 1 mbar:

≤ +/- 0.6 + 1.5

[% of full scale]

Case construction

Fire classification to UL94
Cover: HB
Pressure housing complete: V-2

Diaphragm

Two-component silicone LSR

Temperature influences

Medium and ambient temperature
0 °C to +70 °C
Storage temperature -10 to +70 °C
TC zero point with linear output:
< +/- 0.04 % fs/°C
with root-extracted output:
(from 2 ... 100 % pressure)

< +/- 0.06 in % fs/°C

TC sensitivity
< +/- 0.02 % fs/°C
(linear and root-extracted)

For 1 mbar versions, multiply values
by a factor of 2.5.

Dynamic response / Resolution

Suitable for dynamic measurements.
Response time < 10 ms
Load change < 10 Hz

Resolution:
1 mbar fs version:
< 0.2 % fs
3 to 50 mbar fs versions:
< 0.1 % fs

Pressure connections

Connection pipe

Ø

6.2 mm

Weight

100 grams with display.

90 grams without display.

Installation arrangement

Vertical (factory calibrated),
Pressure connections downwards.
Effect of orientation, see facing
page.

Output signal and power supply

See order code selection table.
Short circuit proof and protected
against polarity reversal. Each
connection against other with max.
+/- supply voltage.

Electromagnetic compatibility: CE
conformity to EC directive 89/336
EEC (EMC) by application of
harmonized standards
IEC 61000-6-3 und EN 61000-6-2.

Load impedance

3-wire cable:
0 ... 10 V > 10 kOhm
0 ... 20 mA < 400 Ohm
4 ... 20 mA < 400 Ohm

2-wire cable:
4 ... 20 mA < Ohm

Current consumption

3-wire cable:
0 ... 10 V < 10 mA
0 ... 20 mA < 30 mA
4 ... 20 mA < 30 mA
2-wire cable: 4 – 20 mA

Electrical connection/Protection standard

Screw terminals for wire and
stranded conductors up to 1.5 mm

2

.
Cable gland with built-in strain
relief Pg 11.
IP 00 without cover
IP 54 with cover

Display

Liquid-cristal, 3 1/2 digit.

Accessories

See order code selection table.

supply voltage – 11 V

0.02 A

The distinct advantages

• Compact construction

• Fast, easy mounting.
Housing incorporates integral
bracket for wall or ceiling mounting.
Snap-on cover with a single screw

• Available with our without LCD
display

• Available with or without root­extracted output

• Attractive price/performance ratio

pFS

p

pFS

p

pFS

p

Legend to cross-section drawing

1 Diaphragm 2 Sensor element
3 P1 higher pressure/lower vacuum
4 Display 5 Amplifier electronics
6 Connection terminals 7 Cover
8 P2 lower pressure/higher vacuum

EDITION 07/2001