VEGA MET307 User Manual

VEGAMET 307 / 308

TIB • Technical Information • Operating Instructions

Signal conditioning
instrument

for continuous level
measurement

• for connection of a
capacitive measuring
electrode

or

• a pressure sensor

VEGA Grieshaber KG

Am Hohenstein 113
Postfach 11 42
D-77757 Schiltach
Phone [phone]
Fax [phone]

A

B

0 4

mA

VEGAMET 308

0

20

40

60

80

100

%

Application

These signal conditioning instruments VEGAMET
307 / 308 are used for level proportional output and
indication of levels (continuous level measure­ment).

The VEGAMET 308 is additionally equipped with
an integral level switch with adjustable switching
hysteresis. Therefore level dependent switching
functions are possible.

The

VEGAMET 307 consists of:

• plastic housing with pluggable multipoint connec­tor (series 300)

• electronics

• front panel with

- analog indicating meter

- mains control lamp

- potentiometer for empty adjustment

- potentiometer for full adjustment

- change-over switch for current output range

0 … 20 mA or 4 … 20 mA.

The VEGAMET 308 consists of:

• as VEGAMET 307

• however additional adjustment elements for the
level switch:

- 2 pressure keys and 2 potentiometers for

adjustment of the switch points

- relay control lamp

- A/B-switch

A measuring system consists of:

• signal conditioning instrument VEGAMET 307 or
VEGAMET 308

• capacitive electrode with oscillator

or

• pressure sensor with oscillator

Additional indicators and auxiliary level switches
can be connected to the current and voltage
outputs.

Level measurement with capacitive electrodes

Electrode, product and vessel wall, or electrode
and product form a capacitor. The capacitance
increases with increasing level.

In either case the oscillator converts this capaci­tance change into a level proportional measuring
signal. This signal is fed to the VEGAMET 307 or
308 for signal conditioning.

Level measurement with pressure sensors

The diaphragm of the pressure sensor converts the
hydrostatic pressure of the product into a linear
movement. This movement is transmitted to the
plunger-type capacitor. The level of the product
therefore changes the capacitance.

Configuration

Function

Power supply 20 … 250 V AC; 48 … 62 Hz

20 … 90 V DC

Power consumption at U

N

approx. 3 VA

Measuring signal Connection line 2-wire, unscreened (standard cable)
input Resistance per conductor max. 50 Ohms

Linearity error 0,1 % measuring range
Temperature error 0,01 % measuring range / 10 K

Adjustment data Empty adjustment range 3,5 … 17 mA

Current difference between
empty and full adjustment: > 600

µA

Indication analog indication 0 … 100 %

Current output Range 0 … 20 mA or 4 … 20 mA

(adjustable)
Load max. 750 Ohm
Resolution 0,05 %
Linearity error 0,025 % measuring range
Temperature error 0,025 % measuring range / 10 K

Voltage output Range 0 … 10 V, max. 1 mA (short-circuit protected)

Resolution 0,05 %
Linearity error 0,025 % measuring range
Temperature error 0,025 % measuring range / 10 K

Relay output
(only VEGAMET 308) Contact 1 spdt

Function two-point switching
Mode A/B
Relay data:
Contact material AgCdO and Au plated
min. turn-on voltage 10 mV

switching current 10 µA

max. turn-on voltage AC 250 V, DC 60 V

switching current AC 2A, DC 1 A

max. breaking power 125 VA, 60 W

Permissible ambient temperature (housing) –25°C … +60°C / –4°F … +140°F
Storage and transport temperature –25°C … +70°C / -4°F … +158°F

Housing Type plastic ABS

Protection IP 40
Dimensions w = 96 mm, d = 76 mm, h = 102 mm

Pluggable multipoint connector (cross section area of conductor) max. 2,5 mm

2

Weight approx. 270 g

Technical data