Post Box 71 02 28
D-30542 Hannover
Kronsberger Straße 25
D-30559 Hannover

Fon +49(0)511-357100-0
Fax +49(0)511-357100-19

New Device! Drive Monitor ES-FDP-AW1

The drive monitor ES-FDP-AW1 contains all functions of the frequency and slippage sensor ES-FDP-FS.., as well as many additional monitoring functions. Due to the integrated position detection by pulse counting, it offers many advantages in tasks such as synchronisation monitoring or shaft or gear break monitoring.

For further information please click here.

Frequency and Slippage Sensor

or Frequency monitor, Slippage monitor, Speed monitor, Frequency relay, Slippage relay, Speed relay, Speed sensor

Our current device: ES-FDP-FS8s and ES-FDP-FS2s

The devices ES-FDP-FS8s (resp. ES-FDP-FS2s) differ to the previous version ES-FDP-FS8n (-FS2n) primarily by the new front panel with membrane keypad.

The arrangement of the operating elements is slightly different, and with the new ES-FDP-FS8s (-FS2s) version, the states of the enable inputs are additionally indicated by LEDs.

The devices are connection- and function-compatible to the previous version ES-FDP-FS8n (-FS2n), all programmable parameters as well as the programming procedure are unchanged.

Frequency and Slippage Sensor ES-FDP-FS8n and ES-FDP-FS2n

With this frequency and slippage sensors can be realised comfortably up to 8 switching channels for monitoring frequency resp. speed and frequency ratios resp. speed ratios. Both of the frequency measuring inputs  and the ratio of the measured frequency can be allocated to the switching channels as desired. 

Time delayed switchings, activating of the switching channels via enabling inputs as well as the output of the actual frequency as standard analog signal give simple solutions to many tasks.


With this frequency and slippage sensor can be detected over-speed, stand still, jammed rollers of conveyor belts or shaft breakage at drives, even with gearbox.


Recording of the minimum and maximum values of the measurands during operation simplify programming of correct switching values well.


  • Easy to programme due to a 2 x 16 characters LC-display with backlight
  • Switching frequencies programmable within the range 0.1 ... 4000Hz  (optional from 0.001Hz)
  • Frequency ratios (slippage) programmable from 0.001 to 9999
  • 2 Measuring inputs for 2-wire and 3-wire proximity switches,

      Namur encoder, incremental encoder or

      high voltage inputs 1,5-400 V AC

  • Measuring principle: period-duration measuring
  • Protection from unauthorised programming by means of a code plug
  • Double-LED display (red/green) for relay status
  • Up to 8 relay outputs with programmable time delays
  • Up to 5 enable inputs with programmable time delays
  • Optional analog output
  • 2 galvanically isolated measuring inputs with open circuit monitoring

Differences to the predecessor device versions ES-FDP-F...x resp. ES-FDP-S...x

The device version ES-FDP-FS…n is designed with a new, up-to-date microcontroller. The immunity to interference could be increased considerably again through this.

The texts on the display can alternatively be displayed in German or English.

The programming of the display contrast is eliminated because the up-to-date display is readable well from a wide viewing angle.

At programmed window functions the passing through the window will be recognized even if there is no measurement inside the window (example: a measurement above the window, the next below the window).


 A programmed averaging function has no more influence on the open circuit monitoring. For a faster detection of an open circuit always the current measured input frequency is evaluated (not the average value).

Also for the calculation of the quotients an averaging function can be activated.

The acknowledgment of error numbers in the display self-test is not made by the key   any more but by pressing the keys and   simultaneously (applies since software version V4.1).


The device offers the following new functions since software version V4.1:

  • The programming of the device can be protected by a password in addition to the code plug.
  • The operating time of the device is recorded and can be read on the display.
  • The number of operating cycles is recorded one by one for every output relay and can be read on the display.
  • The minimum and maximum values of the measurands are recorded during operation and can be read on the display.