Serviceline Industrial Sensors
Serviceline Explosion Protection

Frequency voltage current converter KFU8-FSSP-1.D

  • Limit frequency 40 kHz
  • Voltage or current ouptput
  • Incrementing output
    (Spacing factor 1 ... 9999)
  • Multi-range power pack
  • 2-, 3-, 4-wire and NAMUR sensors as well as rotary encoder connectable
  • Auxiliary power output for sensors
  • Connection via Power Rail
  • Period measurement
  • Display: Input in Hz or 1/min, output in V or mA
  • adjustable updating of indication (0,001 ... 2,5 s)

Please note: All product-related documents, such as certificates, declarations of conformity, etc., which were issued prior to the conversion under the name Pepperl+Fuchs GmbH or Pepperl+Fuchs AG, also apply to Pepperl+Fuchs SE.

Download the complete datasheet as a PDF:

Datasheet excerpt: Technical data of  KFU8-FSSP-1.D

Product Description
Frequency voltage current converter
40 kHz version
Functional safety related parameters
MTTFd100 a
Rated voltage200 ... 230 V AC ; 100 … 130 V AC; 50 Hz
20 VDC ... 30 VDC
Fusingexternal fusing 4 A
Power consumptionAC: < 5 VA
DC: < 5 W
Indicators/operating means
Type4-digit, 7-segment red display, 7 mm digit height
Display interval0.002 ... 9999 Hz or
0.01 ... 9999 min-1
Parameter assignmentkeypad-driven menu
Input 1
Connectionterminals 8-, 9+
Connectable sensor typesNAMUR sensors according to DIN EN 60947-5-6
Open loop voltage8.2 V DC
Short-circuit current6.5 mA
Switching point1.2 ... 2.1 mA Switching hysteresis approx. 0.2 mA
Impedance1.2 kOhm
Input 2
Switching pointhigh: 16 ... 30 V DC; max.10 mA; Ri ≅ 3 kOhm
low: 0 ... 6 V DC
Connectionterminals 7+, 13- sensor supply
terminals 14, 15 NPN/PNP input (galvanically isolated)
Connectable sensor types2-, 3-, or 4-wire proximity switches and incremental rotary encoder
Sensor supply19 ... 28 V DC non-stabilised; ≤ 30 mA short-circuit protected
Analog voltage output0 ... 10 V DC; 2 ... 10 V DC; 30 mA max.; resolution: 12 mV; Ri ≥ 330 Ω (terminal 5+, 6-)
Analog current output0 ... 20 mA; 4 ... 20 mA; resolution: 25 µA; Ri ≤ 600 Ω (terminal 4-, 5+)
Digital incrementing≥ (Ub -3 V), 20 mA, short-circuit proof (Terminals 1-, 2+)
with frequency division Fin /1 ... Fin /9999
Transfer characteristics
Input frequency≤ 40000 Hz, pulse pause/pulse length: ≥ 12 µs
Deviation≤ 0.2 % of full-scale value
Changing interval5 ms (Internal processing time)
Standard conformity
Electromagnetic compatibilityacc. to EN 50081-2 / EN 50082-2
Ambient conditions
Ambient temperature-25 ... 40 °C (-13 ... 104 °F)
Storage temperature-40 ... 85 °C (-40 ... 185 °F)
Relative humiditymax. 80 %, not condensing
Altitude0 ... 2000 m
Operating conditionsThe device has only to be used in an indoor area.
Mechanical specifications
Connection assemblyCaution: Please be aware that the device may only be connected to a switchable power supply. The switch or circuit breaker must be easy to reach and identified as the separator for the device.
Degree of protectionIP20
Connectioncoded, removable terminals , max. core cross section 0.34 ... 2.5 mm2
Construction typemodular terminal housing in Makrolon, System KF
For use in the switch cabinet/switch cabinet module
Mountingsnap-on to 35 mm standard rail or screw fixing


ECLASS 11.027210904
ECLASS 10.0.127210904
ECLASS 9.027210904
ECLASS 8.027210904
ECLASS 5.127210904
ETIM 8.0EC002918
ETIM 7.0EC002918
ETIM 6.0EC002918
ETIM 5.0EC002918
UNSPSC 12.139121007

Documents: KFU8-FSSP-1.D

ManualsLanguageFile TypeFile Size
Handbuch KFU8-FSSP-1.DGERPDF1067 KB

Approvals+Certificates: KFU8-FSSP-1.D

Statements of complianceCertificate No.File TypeFile Size
EU-Declaration of conformity / EU-KonformitätserklärungDOC-1838BPDF162 KB
Canada, USA CSA cUL2137693PDF38 KB

Function: KFU8-FSSP-1.D

The KFU8-FSSP-1.D frequency-voltage/current converter is a device for displaying and monitoring periodic signals, which occur in almost all areas of the automation and processing industry, i.e. frequencies in general and rotational speeds in particular.

Input pulses are evaluated according to the cycle method, i.e. by measurement of the periodicity, and are converted into a frequency or rotational speed by a μ controller. Depending on the measurement range value selected, the μ controller calculates a voltage or current value proportionate to the input frequency and exports this value via a digital-analog converter.

The following analogue signals are available for selection: 0 V ... 10 V, 2 V ... 10 V, 0 mA ... 20 mA, 4 mA ... 20 mA

The serially switched output provides the input frequency which can be subdivided by the adjustable factor (1 ... 9999).

Special consideration was given to the frequently occurring special case of rotational speed measurement during the development of the device. This makes it possible for the display and inputs to be either Hz or in min -1.

In addition, in applications with signal encoders that return multiple pulses per revolution, it is possible to operate automatically at the actual speed of the drive by assigning the number (1 ... 1200).

The frequency/voltage/current converter is supplied with 115 VAC, 230 VAC or 24 VDC. When it is connected with alternating voltage it provides an unstabilised 24-VDC source of power for the signal encoder.

All commonly available two- three- or four-wire proximity switches and incremental encoders on the input galvanically separated by an optical coupler are accepted as a signal source. In addition, two terminals are reserved for connecting proximity switches or incremental encoders in accordance with DIN 19234 (NAMUR).

The input signal frequency in Hz or the speed in min -1 - or the output signal voltage in V or current in mA - appears in a 4-place 7-segment LED display on the front of the device. Parameters can be set with 4 buttons underneath the display.