Материал: m013500e_x06

2.6.5 Supply example

Note

The system supply and the field supply should be separated in order to ensure bus operation in the event of a short-circuit on the actuator side.

L1

L2

L3

N

PE

Shield (screen) bus

Main ground bus

230V

24V

a) Power Supply

on coupler / controller b) Internal System

Supply Module c) Supply Module

passive

d) Supply Module with fuse carrier/ diagnostics

WAGO-I/O-SYSTEM 750

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32• The WAGO-I/O-SYSTEM 750

Power Supply

2.6.6 Power Supply Unit

The WAGO-I/O-SYSTEM 750 requires a 24 V direct current system supply with a maximum deviation of -15% or +20 %.

Recommendation

A stable network supply cannot be taken for granted always and everywhere. Therefore, regulated power supply units should be used in order to guarantee the quality of the supply voltage.

A buffer (200 µF per 1 A current load) should be provided for brief voltage dips. The I/O system buffers for ca. 1 ms.

The electrical requirement for the field supply is to be determined individually for each power supply point. Thereby all loads through the field devices and bus modules should be considered. The field supply as well influences the bus modules, as the inputs and outputs of some bus modules require the voltage of the field supply.

Note

The system supply and the field supply should be isolated from the power supplies in order to ensure bus operation in the event of short circuits on the actuator side.

WAGO-I/O-SYSTEM 750

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2.7 Grounding

2.7.1 Grounding the DIN Rail

2.7.1.1 Framework Assembly

When setting up the framework, the carrier rail must be screwed together with the electrically conducting cabinet or housing frame. The framework or the housing must be grounded. The electronic connection is established via the screw. Thus, the carrier rail is grounded.

Attention

Care must be taken to ensure the flawless electrical connection between the carrier rail and the frame or housing in order to guarantee sufficient grounding.

2.7.1.2 Insulated Assembly

Insulated assembly has been achieved when there is constructively no direct conduction connection between the cabinet frame or machine parts and the carrier rail. Here the earth must be set up via an electrical conductor.

The connected grounding conductor should have a cross section of at least 4 mm2.

Recommendation

The optimal insulated setup is a metallic assembly plate with grounding connection with an electrical conductive link with the carrier rail.

The separate grounding of the carrier rail can be easily set up with the aid of the WAGO ground wire terminals.

WAGO-I/O-SYSTEM 750

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34• The WAGO-I/O-SYSTEM 750

Grounding

2.7.2 Function Earth

The function earth increases the resistance capacity against disturbances from electro-mechanical influences. Some components in the I/O system have a carrier rail contact that dissipates electro-magnetic disturbances to the carrier rail.

Attention

Care must be taken to ensure the flawless electrical connection between the carrier rail contact and the carrier rail.

The carrier rail must be grounded.

For information on carrier rail properties, please see chapter 2.5.3.2.

WAGO-I/O-SYSTEM 750

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2.7.3 Protective Earth

For the field level, the ground wire is placed onto the lower connection terminals of the power supply terminals and further reached through the lower power contacts to the neighboring bus terminals. If the bus terminal has the lower power contact, then the ground wire connection of the field devices can be directly connected to the lower connection terminals of the bus terminals.

Attention

If the connection of the power contacts for the ground wire within the node is disrupted, e.g. due to a 4-channel bus terminal, then the potential has to be resupplied.

The ring feeding of the earth potential can increase the system security. In the event that a bus terminal is ripped out of the potential group, the earth potential is still maintained.

During the ring feeding, the ground wire is connected at the beginning and end of the potential group.

WAGO-I/O-SYSTEM 750

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