FQ(D) - Reed Frequency Meter

Properties

Measuring range from 45 Hz to 65 Hz
Good readability
Minimum temperature influence
Low self-consumption

Description

The FQ(D) reed frequency meters are used for frequency measurement in AC networks. They are available with single measuring system (FQ) and with double system (FQD). The reed frequency meter is the simplest way to display the frequency in AC or three-phase networks. The accuracy can be guaranteed over a very long period of time because the material and the carrier system do not age. Voltage fluctuations up to ±15% and sinusoidal waveforms have no influence on the measurement. The double-tongue frequency meter FQD, with two rows of tongues, can be used to synchronise two networks.

Variants

FQ 72 72 x 72 mm for panel mounting

FQ 96 96 x 96 mm for panel mounting

FQ 144 144 x 144 mm for panel mounting

FQD 72 72 x 72 mm for panel mounting - Double frequency meter

FQD 96 96 x 96 mm for panel mounting - Double frequency meter

FQD 144 144 x 144 mm for panel mounting- Double frequency meter

Mechanical Design

The frequency meter FQ has a vibration measuring system in which a comb with springy reeds is attached to an electromagnet. If the frequency of the applied voltage corresponds to the resonance frequency of a reed of the vibration measuring system, this reed starts to vibrate. The deflection of these reeds is proportional to the square of the applied voltage. The FQD reed frequency meter has two voltage inputs and is therefore also equipped with two vibration measuring systems.

Technical Data

Accuracy class

0,5

Housing

Polycarbonate self-extinguishing, according to UL 94 V-0

Protection class

Housing IP 52
Terminals IP 00 (IP 20 for size 45)
according to 60529: 1989

Mounting position

vertical ± 5°

Self-consumption

Ammeter 0,3...1,2 VA
Voltmeter 1,5...4,0 VA

Environmental Conditions

Climate class

2 according to VDE/VDI 3540

Temperature

Reference range +18 ... +28°C
Working range -25 ... +55°C
Storage -40 ... +70°C

Relative humidity

≤ 80 % (without condensation)

Reed frequency meter:

			Type
Measuring range	Voltage [V]	Reed quantity	FQ 72	FQ 96	FQ 144
47...53 Hz	110, 230	13	•	•	•
47...53 Hz	400, 500	13	•	•	•
57...63 Hz	110, 230	13	•	•	•
57...63 Hz	400, 500	13	•	•	•
45...55 Hz	110, 230	21	-	•	•
45...55 Hz	400, 500	21	-	•	•
55...65 Hz	110, 230	21	-	•	•
55...65 Hz	400, 500	21	-	•	•

Double Reed frequency meter:

			Type
Measuring range	Voltage [V]	Reed quantity	FQD 96	FQD 144
2 x 47...53 Hz	110, 230	2 x 13	•	•
2 x 47...53 Hz	400, 500	2 x 13	•	•
2 x 57...63 Hz	110, 230	2 x 13	•	•
2 x 57...63 Hz	400, 500	2 x 13	•	•
2 x 45...55 Hz	110, 230	2 x 21	•	•
2 x 45...55 Hz	400, 500	2 x 21	•	•
2 x 55...65 Hz	110, 230	2 x 21	•	•
2 x 55...65 Hz	400, 500	2 x 21	•	•