VEGA MET307 User Manual

VEGAMET 307 / 308

TIB • Technical Information • Operating Instructions

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VEGAMET 308

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]

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.

Configuration

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

Function

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

Level measurement with pressure sensors

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.

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.

2	VEGAMET 307 / 308

Technical data

	Power supply			20 … 250 V AC; 48 … 62 Hz
				20 … 90 V	DC
	Power consumption at UN			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		> 600 μA
		empty and full adjustment:
	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 mm2
	Weight			approx. 270 g

VEGAMET 307 / 308

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