SFW-7 Voltage Frequency Guard

SFW-7 Voltage Frequency Guard

with protective functions according to DIN V VDE V 0126-1-1 & DIN VDE-AR-N-4105:2011-08 and monitoring of rate of change of frequency ( ROCOF - Δf to Δt )

The SFW-7 is a device for the monitoring of a three-phase mains system on frequency, voltage, phase sequence, angular shift, rate of change of frequency (ROCOF - requires firmware V1.09 or later) and vector surge. Measurement can be done either with or without neutral conductor.

A separate frequency measuring is available for each of the 3 phases. Detection of vector surge can be assigned to a single phase or all phases. Trigger values are stored & the last 38 triggering events may be retrieved from the device at least. Due to a special internal wiring, the loss of the neutral conductor can be detected in a 3-wire + N - system. The monitoring on nominal voltage and frequency in accordance to DIN V VDE 0126-1-1 (requires firmware version V1.04 or later) & / or DIN VDE-AR-N-4105:2011-08 (requires firmware version V1.09 or later) can be enabled by setting of the corresponding parameters.

Microcontroller- and PC database technology of the SFW-7 provide the conveniently configuration of all settings, using our para- meterisation software 'device manager' (GV_2.exe - Version V2.31 or later recommended). Alternatively values, but not texts, can be entered directly at the device. The input to the device can be protected by use of a PIN. The output of display-texts takes place in 2 languages, default is German and English (switching between languages is possible during operation). Alternative langua- ges can be configured and conveniently made available, by means of our parameterisation software 'device management'.

Note: A separate variant of the SFW-7 is available for measuring voltages ≤ 100 V.

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Technical data

Auxiliary Voltage 24V DC (18 ... 36 V)
optionally 230V AC / 12 V DC
Power consumption approx. 4 W at 24 V DC,
approx. 6 VA at 230 V AC
Digital Inputs LowActive
(Contact Voltage 12 V, 5 mA,
cables no longer than 3 m
Relay outputs 230 V / 50 Hz / 2 A (potential-free)
Analogue Outputs 0 ... 10 V +/- 0.05 V max. 10,5 V
Measuring Range approx. 50 up to 230 / 400 V,
tolerance < 0,5 % of full scale
( 270 / 480 V )
Frequency Measurement 35.0 Hz up to 65.0 Hz
from approx. 60 V L-N on
adjustable in 0.1 Hz steps
repeatability +/- 0.05 Hz
Ambient temperature -20 ... +55 ºC
Housing Dimensions W / H / D 100 x 75 x 110 mm
DIN top-hat rail mounting 35 mm
Download PDF db Data sheet
Ordering information SFW-7 / 400 V / 24V DC: E2085
SFW-7 / 400 V / 230V AC: E2086
SFW-7 / 100 V / 24V DC: E1573
SFW-7 / 100 V / 230V AC: E1574