KEB 7608000-4001

2.5.2 Winding and insulation system
The insulation materials we use ensure insulation class 155 (F) to EN 60034. Therefore,
the winding temperature may be max. 105 K at a coolant temperature of +50°C.
The insulation system of the motors is designed such that they can be connected to an
inverter with a maximum DC link voltage U
link max.
= 840 V DC (constant 690 V DC).
U
link max.
is the maximum value of the DC link voltage which is only transient and
approximately equivalent to the inception voltage of the braking shopper or of
the regenerative unit.
2.5.3 Holding brake
Thebuilt-inholdingbrakeisusedtoxthemotorshaftwhenthemotorisatstandstill
or de-energized. It is a spring applied brake which operates on the power off principle,
i.e. the brake is effective when the motor and the brake power is de-energized, thus the
motor shaft is held.
Holding brakes are operated on DC current. The rated voltage is 24 V. They can be con-
nected to a central DC voltage supply. Overvoltages are not permitted, even not tempo-
rary. The excitation current ripple must be less than 20 % to ensure reliable opening of
the brake and prevent disturbing humming noises.
ATTENTION
Holding brake is not a working brake!
Check the proper functioning of the brake (optional) after installing the
motor. The optional holding brake is only designed for a limited number
of emergency brakings. Never use it as a working brake.
ATTENTION
Motor rotation in spite of an active brake!
Modern(eld-oriented)frequencyinvertersareabletoproduceahigh
torqueevenatlowmotorspeeds.Iftheinverterhasasufcientcur-
rent reserve, a multiple of the rated motor torque can be produced. In
this case the motor shaft may turn even if the holding brakle is applied,
because the holding torque of the brake is exceeded.
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PRODUCT DESCRIPTION