Watson-Marlow MM420 - Manual (Page 145)

Issue 10/06 3 Functions
MICROMASTER 420 Operating Instructions
6SE6400-5AA00-0BP0 145
Set the load holding
The opening / closing times of mechanical brakes are subject to certain
fluctuations; this is the reason that a weight equalization function must be
parameterized in the frequency inverter for the time P1216 and P1217. The
following parameters must be defined so that the axis cannot sag (i.e. the axis
cannot drop/fall).
♦ In order that the motor can immediately establish a torque after an ON
command, the magnetizing time P0346, determined with the quick
commissioning, may not be reset. This is the reason that parameter P0346
should be checked for the weight equalization.
Typical magnetizing times for 4-pole 1LA7 motors are:
0.12 kW 50 ms 5.50 kW 250 ms
1.50 kW 100 ms 7.50 kW 300 ms
♦ The min. frequency P1080 should approximately correspond to the rated
motor slip (P1080 ≈ r0330[Hz])
♦ In addition, the voltage boost should be adapted:
- constant voltage boost
P1310 ≈ 90 % (empirical value)
- voltage boost when accelerating
P1311 ≈ 50 % (empirical value)
Connecting-up the motor holding brake control
♦ Directly connected to the relay output
COM
NO
10
11
CPU
MICROMASTER 420
M
3 ~
=
Motor with
motor
holding brake
Fig. 3-60 Direct motor holding brake connection