Frequency inverter ER24 G

The most important advantages:

- Increased protection class
- Unique safety function
- Maintenance free


The universal drive from BLEMO® -
for all applications with synchronous motors and Asynchronous motors.


Frequency inverter with IP65/66 protection for speed adjustment
of synchronous and asynchronous motors, 0.18 to 7.5 kW, -200 to 500 V, 1~ and 3~.

ER24G – V7 IP65 – 5 tap changer


The ER24G is the further development of the successful ER22G series. This new product range operates synchronous and asynchronous motors.
With its outstanding functionality, the ER24G can be used for all tasks in mechanical and plant engineering. New features include the integrated safety functions STO, SLS, SS1, SMS and GDL, a direct PTC input and an integrated synchronous motor function in open loop mode. Programmable function blocks allow the execution of e.g. Boolean and arithmetic functions, timers, counters, comparators and short automation sequences.
The protection class has been increased to IP66 for version 1 (V1) and to IP65 for version 2 (V2) with integrated switches.

Standard features

  • 150 application-specific functions
  • varnished boards
  • RoHs, WEEE compliant (recycling rate: 88%)


  • 4-digit 7-segment display
  • EMC filter (IEC 61800-5-1)
  • PTC thermistor input
  • Input STO (also dual-channel)
  • PID controller
  • Modbus, CANopen


  • multilingual plain text display
  • PROFIBUS DP V1, DeviceNet, EtherCAT, Ethernet/IP, Modbus TCP, POWERLINK and ProfiNet

Integrated security Without further external components

STO: Safe Torque Off
Free run-out to standstill due to motor torque separation.
SLS: Safely reduced speed
Deceleration, maintenance of a predefined speed.
SS1: Safe stop
Stopping the motor according to a predefined, safely monitored ramp. Checks whether the motor is completely stopped or has reached a minimum predefined speed; then activates the STO function.
SMS: Safe monitoring of two motor speeds
STO is activated when the limit speeds are reached.
GDL: Safe release of safety gates
Safe control of safety gates with delay of safe exit.
Safety Integrity Level (SIL 1, 2 or 3) according to
IEC 61508 (Parts 1 and 2)
Performance Level (PL e) according to
ISO 13849-1/-2 Category 3

Synchronous motors

The new control algorithm up to 599 Hz for permanently excited synchronous motors without feedback ensures optimized performance and easy connection of the motors. The sensorless vector control provides full torque from the lowest speeds. The patented pole wheel position measurement supports all synchronous motor types and also stepper motors.


  • Version 1: Basic unit without built-in switches and setpoint potentiometer, protection class IP66.
  • Version 1S: Basic unit, built-in: lockable switch-disconnector, black
  • Version 2: Complete unit, built-in: lockable load-break switch red, setpoint potentiometer and start/stop or direction of rotation preselection switch, protection class IP65.
  • Version 4: Change-over switch for FI/mains (emergency) operation, setpoint change-over switch, setpoint potentiometer, protection class IP65
  • Version 7: Basic unit with built-in 5-step switch, protection class IP65.

your benefits

Areas of application

Frequently asked questions about the product

All page numbers refer to the ER24 Programming Guide.

Switch on the power supply of the inverter without giving a run command (start command +24V and DI1). Observe connection diagram!

Set the following settings:

  • Set the rated frequency of the motor [Standard Motor Freq.] (bFr), page 84, if the frequency is not 50 Hz.
  • Only set the motor parameters in the menu [ANTRIEBS DATEN] (drC-), page 103, if the factory configuration of the inverter is unsuitable.
  • Set the application functions in the menu [INPUTS / OUTPUTS CFG] (I_O-), page 124, the menu CONTROL] (CtL-) menu, page 153, and the [APPLIKATIONS-FKT .] (FUn-) menu, page 167, only if the inverter factory configuration is unsuitable.

Set the following parameters in the [SETTINGS (SEt-)] menu:

  • [Hochlaufzeit] (ACC), page 85, and [Auslaufzeit] (dEC), page 85.
  • [Kleine Frequenz] (LSP), page 85, and
  • [Große Frequenz] (HSP), page 87.
  • [Therm. rated current] (ItH), page 85.

After all preparations have been completed, the run command / start command can be wired. (FU starts and drives off!)

  1. To achieve electromagnetic compatibility, the inverter must be operated with a built-in or external RFI filter.

  2. When using shielded cables between the inverter and the motor, the shield must be connected to earth at both ends. Cable interruptions should be avoided as far as possible. If it is necessary to separate the cable, e.g. in order to install a motor contactor, then the cable shielding must be connected through as directly as possible. It is important to ensure that the lowest possible HF impedance is achieved.

  3. The shorter the cable, the lower the radio interference and leakage current. The maximum possible cable lengths must be taken into account.

  4. To avoid interference with the control inputs, control cables should always be shielded. The shield must be connected to the cable clamp provided on the inverter. If the shield is also connected to a control unit, ensure that the ground points are at the same potential.

  5. Control cables should not cross power cables if possible. Where this cannot be avoided, a right-angle intersection is recommended.

  6. Separate routing of control and power cables should be aimed for. If the cables have to be laid in parallel, e.g. on the same cable route, the greatest possible distance (> 20 cm) should be chosen.

  7. The shielding of the installed cables should have a low RF impedance if possible. Therefore, copper braiding is preferable to steel braiding.

  8. The HF contact resistance at the connection points between the shielding and the housing must be kept as low as possible. Dirt, paint and insulation residues on the housing and shielding in the area of the connections must therefore be removed. In principle, the cable clamps or crimp connections provided for this purpose should be used to connect the shielding. The use of earthing glands is advantageous.

  9. The shielding should be applied to the housing as close as possible to the cable terminals. Longer, free cable ends act as antennas.

  10. For unshielded cables, the cable cores should be twisted and output filters should be used.

In principle, it is possible to operate a motor with low power on a frequency inverter with higher power.
The ratio between motor and inverter power is important here.
Experience shows that the ratio of 1:4 should not be exceeded.

For example, it is not recommended to operate a 0.75kW motor with a 30kW BLEMO frequency inverter.
This combination can be used for test purposes, but the motor phase monitoring must be deactivated.

  1. Graphic display via a Modbus cable with the Modbus interface
    (RJ45 connector) to the ER24 frequency inverter.
  2. Connect the mains voltage.
  3. Press “ESC” repeatedly until the main menu appears.
  4. Select item “4 Open / Save as” and press “OK”.
  5. Select item “4.1 Copy to inverter” and press “OK”.
  6. Select the desired data set (e.g. “File 1”) and press “OK”.
  7. The submenu “Download group” appears. Now select “All” and press “OK”.
  8. The display shows: “Check the connection to the inverter” “ESC = Abbr. OK=Take over”, Now press “OK”.
  9. After error-free saving, the display shows: “Transmission complete” “OK OR ESC TO CONTINUE”.
    Now press “ESC” or “OK”.
  10. Press “ESC” several times to return to the starting point (e.g. “Main menu”).

Assuming that the ER24 is in the factory default setting, the following are available in stopped mode
state (display: rdY), the following settings must be made:

Press ENT and select the COnF mode, then press ENT again.

2. first select the item “FULL”, scroll down to the parameter LAC and select this parameter.
to AdV or EPr, >press ENT for 2s to save, then press ESC,
until LAC appears in the display again.

Scroll to the Control CtL- menu, press ENT, locate the FR2 parameter andpress
Set UPdt

4. set parameter rFC to FR2 in menu Control CtL-.

Call up the Application functions FUn- menu and select the UPd- parameter there.

Now call up the parameter “USP” and enter a value for the assignment “+ speed”.
Select free input e.g. LI5

Finally, call up the “dSP” parameter and select a free parameter for the “- speed” assignment.
Select input e.g. LI6
Via input DI5 the speed is increased and via input DI6 the speed is reduced.

1. parameter FrY[PARAMETER GRUPPE] Call up and select ALL [Alle], save with ENT, and
then exit the parameter with ESC.

2. call up parameter GFS [GOTO WERKSEINST] and select YES [Ja], then press ENT at least
Press and hold for 2 seconds to save.