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4 Characteristics
MITSUBISHI CNC
(3) Magnetic brake power supply
(a) Brake excitation power supply
[1] Prepare a brake excitation power supply that can accurately ensure the attraction current in
consideration of the voltage fluctuation and excitation coil temperature.
[2] The brake terminal polarity is random. Make sure not to mistake the terminals with other circuits.
(b) Bake excitation circuit
When turning OFF the brake excitation power supply (to apply the brake), DC OFF is used to shorten
the braking delay time.
A surge absorber will be required. Pay attention to the relay cut off capacity.
<Cautions>
• Provide sufficient DC cut off capacity at the contact.
• Always use a surge absorber.
• When using the cannon plug type, the surge absorber will be further away, so use shielded wires
between the motor and surge absorber.
1. Always install a surge absorber on the brake terminal when using DC OFF.
2. Do not pull out the cannon plug while the brake power is ON. The cannon plug pins could be
damaged by sparks.
CAUTION
24VDC
SW1
SW2
VAR1
ZD1
ZD2
VAR2
PS
100VAC or
200VAC
(b) Example of DC OFF
PS
ZD1,ZD2
VAR1,VAR2
Magnetic brake circuits
Magnetic brake 1
Magnetic brake 2
: 24VDC stabilized power supply
: Zener diode for power supply protection (1W, 24V)
: Surge absorber