Relay Modules
Motor brake relays
Motor brake relays are used with view to safety and efficiency. With braking currents up to 600 A DOLD braking units allow a reliable deceleration of asynchronous motors up to 160 kW. They can be used to bring your machines to a standstill within 10 s as required by the European Directive on Machinery.
- Easy installation, also in existing plants
- Free from wear and maintenance
- Adjustable braking currents allow optimal tailoring to machines and plants
- Automatic zero-speed monitoring ensures precisely accurate braking current cutoff and spares time-consuming readjustments
- Thermistor motor protection prevents inacceptable motor heating
What is DC Injection Braking?
DC Injection braking is an effective electrical method of stopping a rotating AC asynchronous motor.
How does it work ?
An AC electrical motor works on the basic principle of opposing magnetic poles attracting each other. If you create a rotating magnetic field in the stationary (stator) windings of a motor, a magnetic field of the opposite polarity in the rotating (rotor) windings will naturally want to follow it trying to align itself (Fig.1).
If you were to then create a stationary magnetic field in the stator, the attracted opposing fields in the still rotating rotor windings will try to align themselves with the stationary field, creating a strong braking force. This is what happens when a DC current is Injected into the ‘Stator’ windings of a motor.
Application
- Wood working machines
- Centrifuges, belt conveyor drives
- Textile machines
- Mills, grinding machines
Motor brake relay MINISTOP | ||||||||
| Function | Braking current adjustable up to [A] max. |
Braking time adjustable up to [s] max. |
Automatic zero- monitoring |
Temperature monitoring |
External brake contactor required |
Diverse signalling outputs |
Width [mm] |
Type |
|---|---|---|---|---|---|---|---|---|
| Motor brake relay | 60 | 30 | + | + | + | 90 | BI 9034 | |
| Motor brake relay | 25 | 11 | + | 45 | BA 9034N | |||
| Motor brake relay | 80 | 20 | + | + | 90 | BI 9023 | ||
| Motor brake relay | 25 | 15 | + | optionally | + | 100 | BN 9034 | |
| Motor brake relay | 600 | 320 | + | optionally | from 100 A | + | 110 | GB 9034 |
| Softstart with d.c. brak | 60 | 30 | + | + | 90 | BI 9028 | ||
* Following product are also available: | ||||||||