Estun E21S, Руководство по установке

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Inductive load, frequency converter and servo driver inside the cabinet shall
be kept away from power line, encoder cable and signal line.
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Earth potential difference between different equipment is the smaller the
better, theoretically, zero is the best.
7.3.2 Instructions to E21S electricmagnetic compability
installation
1. E21S may be installed outside the cabinet. If work environment is poor, keep
E21S close to cabinet as much as possible.
2. Metal housing shall connect to protective ground via earth conductor, and
ground resistance shall be no higher than 0.3 ohm.
3. Cabinet must be ground well to avoid personal injury or death caused by
electricity leakage.
4. Power line, encoder cable and signal line must be away from strong current and
inductive load. Do not lay in parallel.
5. Signal line (I/O port cable) is the shorter the better. If long distance wiring is
required, try to keep away from strong interference source.
6. Two 24V power supplies are recommended, one for supply power to internal
circuit, the other for IO port power supply.
7. Encoder cable uses shield line. The shield layer and metal housing connect to
each other in large area. Try to avoid “pigtail” connection.
7.3.3 Install freewheeling diode on relay
When inductive load is cutoff, instant high voltage will generate, such as coil and
contactor of relay.
To avoid damage to system circuit by high voltage, necessary protection measures
must be taken.
E21S output port load is DC relay, protective measures are as follows:
Add bleeder diode on coil, clamp voltage on both ends of coil. But some off-delay
will be caused.
Figure 7-3
Relay coil connect freewheel diode