Siemens MICROMASTER 420 0.25 kW 1-phase frequency inverter, 230 Vac to , 6SE6420-2AB12-5AA1 6SE6420-2AB12-5AA1 Hoja De Datos

24

MICROMASTER 420 Operating Instructions

6SE6400-5AA00-0BP0

The inverters are designed to operate in an industrial environment where a high level of
EMI can be expected. Usually, good installation practices will ensure safe and trouble-
free operation. If you encounter problems, follow the guidelines stated below.

♦  Ensure that all equipment in the cubicle is well grounded using short, thick grounding

cable connected to a common star point or busbar

♦  Make sure that any control equipment connected to the inverter (such as a PLC) is

connected to the same ground or star point as the inverter via a short thick link.

♦  Connect the return ground from the motors controlled by the inverters directly to the

ground connection (PE) on the associated inverter

♦  Flat conductors are preferred as they have lower impedance at higher frequencies

♦  Terminate the ends of the cable neatly, ensuring that unscreened wires are as short

as possible

♦  Separate the control cables from the power connections as much as possible, using

separate trunking, if necessary at 90º right angles

♦  Whenever possible, use screened leads for the connections to the control circuitry

♦  Ensure that the contactors in the cubicle are suppressed, either with R-C suppressors

for AC contactors or 'flywheel' diodes for DC contactors fitted to the coils. Varistor
suppressors are also effective. This is important when the contactors are controlled
from the inverter relay

♦  Use screened or armored connections for the motor connections and ground the

screen at both ends using the cable clamps

Safety regulations must not be compromised when installing inverters!